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D. degree in Mass Media fig” 4/” f Major Professor’s Signature 07/; 2/47 Date MSU is an affinnat‘ive-action, equal-opportunity employer PLACE IN RETURN BOX to remove this checkout from your record. TO AVOID FINES return on or before date due. MAY BE RECALLED with earlier due date if requested. DATE DUE DATE DUE DATE DUE 6/07 p:/ClRC/DateDue.indd-p.1 SEARCHING FOR IMPLICIT MARKET PRICES FOR KOREAN BROADCAT ADVERTISING TIME: A HEDONIC APPROACH By Myeng Ja Yang A DISSERTATION Submitted to Michigan State University In partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Telecommunication, Information Studies and Media 2007 ABSTRACT SEARCHING FOR IMPLICIT MARKET PRICES FOR KOREAN BROADCAST ADVERTISING TIME: A HEDONIC APPROACH By Myeng J a Yang Korea Broadcast Advertising Corporation (KOBACO), the public media representative established by the Korean government in 1981, monopolizes the sale of broadcast advertising time for all terrestrial TV and. radio stations in South Korea. In setting prices for advertising time, the public media representative has been alleged by industry participants to have behaved as an industry coordinator subsidizing public interest programs carried by TV and radio broadcasters. Hence, it is suspected that KOBACO has tied under-priced advertising time in regular programs with over-priced advertising time favored by regulators (Jung, 2005; Kim, 2006). However, discussions on issues of price distortion and subsidy in the Korean broadcast advertising market have not been supported by well-designed empirical studies. Using actual transaction data, this study estimates implicit market prices for Korean broadcast advertising time. Those prices were estimated using the hedonic regression approach where price was assumed to be determined by the characteristics of advertising time including audience Size, demographic compositions, and parts of day when programs were broadcast (i.e., daypart). This dissertation’s empirical challenge is to find and construct market valuations of advertising spots in the Korean broadcast advertising market where published rate cards might not reflect market values. Drawing upon the bundling literature, the proposed model assumed that package prices reflect market values for advertising Spots although individual spot prices might not. However, actual package data were not available for the study. Alternatively, package prices were constructed in terms Of advertising budgets spent by an advertiser in a network through a particular advertising agency. This study found evidence for price distortion and subsidy in the Korean broadcast advertising market. However, the Size of distortion or subsidy was smaller than estimations made by previous studies. Implicit market prices for most types of advertising time in the major TV programs were estimated to be higher than the KOBACO set prices while implicit market prices for most types of advertising time in religious broadcasters’ programs were estimated to be lower than KOBACO set prices. In terms of overall revenue, major networks should earn 1.42 % more, while religious broadcasters should earn 36.36% less, at implicit market prices, than they earned at KOBACO prices. AS the first econometric analysis using actual transaction data, this study contributes to KOBACO’S exploration to improve its pricing formula. In addition, the reform of Korean broadcasting policy and efficient decision-making by industry participants will be assisted by the study. Beneficiaries may include content providers, broadcasters, advertisers, and other media firms. The study also contributes to the design of an explicit subsidy system Should policymakers decide such a policy is appropriate. Particularly, estimated market value deviations from corresponding entries in published rate cards provide estimates of the size of rate restructuring that will occur when competition iS introduced. Copyright by Myeng J a Yang 2007 This dissertation is dedicated to my husband, Michael Lee, for his unconditional love and support, my son, Hyun-seok Lee, for his patience awaiting my return from the library, and God, for making all this possible. ACKNOWLEDGMENTS Not all which exists is visible. Some recognize it but some not. Some develop it but some not. Therefore, some ask for help and some give help to fill the gap. I could complete my doctoral program as I was able to meet those who provided to me what I did not have. In this space, I express my sincere appreciation to them. First, I thank members Of my dissertation committee for their constant encouragement and guidance. I am extremely grateful for the invaluable support I received from my dissertation director and committee chair, Dr. Steve Wildman. He provided me with the necessary intuition, instruction and innovation to design and draft my dissertation and he gave those fine elements abundantly, as fathers give to their children. Dr. Kurt DeMaagd has been a superb counselor to me. Especially, his suggestion on research models was a major force for me and for my committee members to have confidence in my embarking on this dissertation journey. Also, his statistical support was substantially helpful. Dr. Steve Lacy always has been a haven I visited whenever I had concerns. Thanks to his comments and ideas, I could have, did have, the courage to take the final model whose merits I had resisted seeing. Dr. Johannes Bauer instructed me what to see broadly and what to see narrowly. His comments were always pinpoint—precise. I am indebted to him for much. Dr. Dennis Gilliland at the Center for Statistical Training and Consulting was extremely helpful. He reviewed every detail of my dissertation and provided highly specific solutions to concerns. Serendipitously, both he and I settled independently on the same model to Solve the multicollinearity problem. His kindness is unforgettable. vi Additionally, I thank Jung-Eun Lee for developing programs needed to conduct data analysis. First, She developed a program counting the number of ad contracts using data of contract durations and aired dates. Second, she developed a program calculating weighted averages of the SBS’ regional audience ratings. Without her assistance, the time required to complete dissertation would have been much longer. My parents in law, Sang Won Lee and Kyoung Ae Lee, my mother, Bong Choon Nam, my sisters and brothers, Wha Ja Yang, Yeon Soon Yang, Kyoung Whan Yang, and In J a Yang and My lovable niece, Hye Kyoung Park deserve for special thanks for their love and encouragement. My friend, Eunsun Lee, showed me what generosity is for. She has been there for me whenever I need someone to talk to and need hands. My friends in Prayers’ Meetings also deserve sincere thanks for their prayers and encouragements. Eun Sil Lee, Joung Wha Choi, Miran Kim, Mira Yoo, Yoomi Chin, Hyunjoo Ha, Hyunjoo Choi, Mi Kyoung Kim, Jee Young Bang, Myung Sun Huh, Jeonghee Noh, Jin Young Choi, and Christina Dokter. For the past four years, they have been my family. I offer special thanks to Hyung Bae Park of Korea Broadcast Advertising Corporation (KOBACO) for affording me access to data. This study was possible thanks to his cooperation, and was initiated and proceeded via discussions with him. Extensive interactions with members of the KOBACO staff, especially with Yong Ho Lee, have been helpful in clarifying concepts and understanding the environment they work in. My doctoral study was funded by Korea Telecom (KT). Also, my research was funded partially by a dissertation fellowship from the Michigan State University Graduate School. I am grateful to those institutions for their support. Most of all, I thank God. He is the Only One who made all this possible. vii TABLE OF CONTENTS LIST OF TABLES .......................................................................................................... x LIST OF FIGURES ........................................................................................................ xii CHAPTER 1 ...................................... ' ............................................................................. 1 INTRODUCTION .......................................................................................................... 1 Market Structure and Pricing Mechanism .............................................................. 4 Rationale for the Study ........................................................................................... 15 CHAPTER 2 ................................................................................................................... 19 LITERATURE REVIEW ............................................................................................... 19 Studies on Prices for Korean Broadcast Advertising Time .................................. 19 Hedonic Price Estimation Studies and Advertising Time Prices ............................ 24 Implicit Market Prices for the Bundled Products ................................................... 30 CHAPTER 3 ................................................................................................................... 32 EMPIRICAL MODEL OF IMPLICIT MARKET PRICES ........................................... 32 Estimation of Implicit Market Prices ...................................................................... 32 Estimation of Price Distortion ................................................................................ 43 Estimation of Subsidies .......................................................................................... 43 CHAPTER 4 ................................................................................................................... 45 METHODOLOGY ......................................................................................................... 45 Data ......................................................................................................................... 45 Measurements ......................................................................................................... 47 Package Price .................................................................................................. 47 Audience Size per Demographic Characteristic ............................................. 49 Daypart ............................................................................................................ 51 Construction of Packages ................................................................................ 52 CHAPTER 5 ................................................................................................................... 53 RESULTS ....................................................................................................................... 53 Model Re-specification ........................................................................................... 55 Estimation of Implicit Market Prices .................................................................... 60 Implicit Market Prices .................................................................................... 66 Revenues estimated with Implicit Market Prices ........................................... 68 Further Analysis ...................................................................................................... 72 Package Size Effect ........................................................................................ 72 Effect of Demographic Composition .............................................................. 73 Selling Major Radio Time in Package with Major TV and Religious Radio Time ..................................................................................................... 76 Significance of Difference Between KOBACO Prices and Implicit Market Prices .................................................................................................. 81 Comparison of present findings to those of the other studies ......................... 81 viii Diagnostic Analysis ................................................................................................ 90 Normalin ........................................................................................................ 90 Linearity and Homoscedasticity ..................................................................... 94 CHAPTER 6 ................................................................................................................... 96 DISCUSSION AND CONCLUSIONS .......................................................................... 96 Implications ............................................................................................................ 101 Implications for Media Policy and Industry .................................................. 101 Implication for the Studies of Advertising Prices ......................................... 104 Limitations .............................................................................................................. 1 05 Conclusions ............................................................................................................. 107 APPENDIX ............................................................................................................. 108 REFERENCES ............................................................................................................... 119 ix LIST OF TABLES Table 1. Variables and Data .......................................................................................... 38 Table 2. Descriptive Statistics _ Before Outlier Removed ........................................... 54 Table 3. Descriptive Statistics __ After Outlier Removed ............................................. 56 Table 4. Pearson Correlations of Package Data ............................................................ 57 Table 5. Pearson Correlations of Audience Ratings in the Major TV Networks. ........ 59 Table 6. Regression Estimates for Average Package Price .......................................... 61 Table 7. Regression Estimates for Average Audience Seconds of TV Block Ads 63 Table 8. Hierarchical Regression of Average Audience Seconds of TV Block Ads: Daypart of TV block ads in the 2" Stage ....................................................... 64 Table 9. Hierarchical Regression of Average Audience Seconds of TV Block Ads: Other than TV block dyparts in the 2nd Stage ................................................. 65 Table 10.1. Implicit Price Estimation for the Maj or TV Networks. ............................. 67 Table 10.2. Implicit Price Estimation for the Religious Broadcasters .......................... 69 Table 11.1. Revenue Estimation for the Major TV Networks ...................................... 70 Table 11.2. Revenue Estimation for Religious Broadcasters ....................................... 71 Table12.1. Package Size Effect on APPU .................................................................... 74 Table12.2. Package Size Effect on Average Price per Audience Second .................... 74 Table 13. Demographic Composition Effect ................................................................ 75 Table 14. Regression Output Including Major Radio ................................................... 77 Table 15.1. Price Estimation for the Major TV Including Major Radio. ..................... 78 Table 15.2. Price Estimation for the Religious Broadcasters Including Major Radio. ........................................................................................................ 79 Table 15.3. Price Estimation for the Major TV Including Major Radio. ..................... 80 Table 16.1. Revenue Estimation for the Major TV Networks Including Maj or Radio .......................................................................................................... 82 Table 16.2. Revenue Estimation for the Religious Broadcasters Including Major Radio ......................................................................................................... 83 Table 16.3. Revenue Estimation for the Maj or Radio Broadcasters Including Major Radio ............................................................................................... 85 Table 17.1 Mean Difference Test for Major TV Program Ads .................................... 86 Table 17.2. Mean Difference Test for Major TV Block Ads ....................................... 87 Table 17.3. Mean Difference Test for Religious Radio Program Ads ......................... 88 Table 17.4. Mean Difference Test for Religious Radio Block Ads .............................. 89 Table 18. Comparison of Findings with those of Previous Studies .............................. 91 Table 19. Residual Statistics. ........................................................................................ 92 Table 20. Skewness and Kurtosis . ............................................................................... 93 Table 21.1. Comparison between the Estimators of Implicit Market Prices and KOBACO Set Prices for Major TV. ......................................................... 99 Table 21.2. Comparison between the Estimators Implicit Market Prices and KOBACO Set Prices for Minor Radio and Major Radio. ........................ 99 Table 21.3. Estimator Comparison. .............................................................................. 100 Table 22. The Comparison of Price Ranges. ................................................................ 103 xi LIST OF FIGURES Figure 1. Transactional Relationships between Organizations ........................................ 8 Figure 2. Types of Advertising Time ............................................................................... 10 Figure 3. Dayparts for TV and Radio Programs .................. 13 Figure 4. Histogram of Regression Standardized Residual ............................................. 92 Figure 5. Normal P-P Plot of Regression Standardized Residual. .................................. 95 xii CHAPTER 1 INTRODUCTION In the Korean broadcasting market, the system for selling advertising time is unique. The Korea Broadcasting Advertising Corporation (hereafter, KOBACO), the public media representative established by government in 1981, is a monopoly intermediary coordinating the sales of broadcast advertising time for all terrestrial TV and radio stations. Officially, the reason for founding KOBACO was to protect public interest and ensure content diversity, likely to be suboptimal in a competitive ad-supported market for audience with limited competition. This is consistent with the predictions of numerous program choice studies (e.g., Beebe, 1977; Owen and Wildman, 1992; Spence and Owen, 1977; Steiner, 1952). It also has been said by researchers that regulators have considered a balanced allocation of advertising budgets throughout the media to be an important policy goal. Restrictions on the pricesiof broadcast advertising time have been perceived as contributing to financial stability Of other competitive media such as newspapers (Choi, 2005; Jung, 2005). In addition to establishing a monopoly in the sale of broadcast advertising time, the Korea Broadcast Law has regulated quantity as well as format and frequency of broadcast advertising (Clause 73). Advertising time per program cannot exceed 10%I of ' The 10% rule applies to the program advertising broadcast right before or right afier programming. Other types of ads are also available, including station break ads, caption type ads, and ads associated with time announcements (see Page 11 for details). In sum, 16.7% of program airtime is available for advertising. TV program time and it is not permissible to insert commercials into programs (The Order of Korea Broadcast Law, 2006, Clause 59).2 Under this monopoly system, KOBACO has been at the center of criticism regarding the issues of packaged sale of advertising time and an inefficient pricing formula (Park and Lee, 2007). As KOBACO sells multi-entity and multi-program advertising time concurrently, the organization has been alleged to tie under—priced regular program spots with over-priced spots in programs favored by the regulator (Choi, 2005; KFTC, 2004; Jung, 2005 ; Yoo, 2005). Summarizing the problems ascribed to the monopolized broadcast advertising sales market, Yoo (2005), a director of the Korean Fair Trade Commission (KF TC), identified tying as one of KOBACO’S monopolistic behaviors likely to distort advertising prices and to cause inefficient allocation of resources. Proponents of the current monopoly system, such as non-governmental organizations (N GOS), newspapers, and financially weak broadcasters, have argued that abolishing the current KOBACO system would increase the prices for ad time on the major TV networks while causing a financial crisis for minor broadcasters (Choi, 2005; Jung, 2005). Previous studies (Jeon, 2004; Jung, 2005) claimed that KOBACO’S packaging practice has been tolerated or, in a sense, facilitated by the regulators to ' promote their policy goals: subsidizing financially weak broadcasters and “public interest” programming within the major networks (Park and Lee, 2007). Packaging can be a mechanism for implementing a subsidy as it forces advertisers to purchase ad time for public interest programs at a higher price than its value while purchasing ad time in regular programs at a lower price than its value. 2 In many countries, TV and radio commercials are delivered within and between programs. Those broadcast between programs are called “adjacencies.” If this terminology is used, only “adjacencies” are permitted in Korea. More clearly, a recently published paper (Park and Lee, 2007) describes the existence of a packaging system in the Korean broadcast ad time market as a fact. In the paper (of which the first author is a KOBACO researcher) the authors argue that, although there is a tendency for the prices not to be determined in the market, demand and supply are equated in the market through the packaging practice where ad time in programs whose values are higher than KOBACO set prices is sold in combination with ad time in programs whose values are lower than KOBACO set prices. So, prices for packages are market prices but component prices may not be. Despite all the policy and academic debates, however, there has been no explicit evidence of such subsidies in the market except a recent paper (Park and Lee, 2007). Officially, KOBACO has set prices for ad time based on a published formula and each contract is recorded as if individual spots were sold independently at the price specified by the formula. What has been conducted in the market is the profit regulation of the major networks3 and the implicit obligation imposed on KOBACO to sell advertising time for programs believed to provide an important public service, such as traffic safety, education, religious or local programming, regardless of technology. As the government granted TV or radio licenses for the public broadcasting, it required KOBACO to secure the minimum revenues necessary for public interest programs to be produced continuously (Park and Lee, 2007). In a Situation where there is no explicit subsidy system available for the public broadcasting services, an implicit subsidy mechanism tends to be accepted as reasonable by the industry as well as the public. The implicit 3 Profits of the major networks have been regulated in many countries as their advertising prices have significant impacts on those of other firms within or outside of broadcasting industry (Lee, 2000). For example, in the U.K., Channel 4 revenues are regulated not to exceed 14% of total advertising revenue, and 50% of excessive revenue is to be remitted to [TV (Min, 1995). In Netherlands, public broadcaster’s advertising revenues are regulated to maintain balance with other media (Lee, 1995*). subsidy system is believed to operate by forcing advertisers to buy packages of both commercial and religious slots whose prices are arguably biased downward for the commercial programs but upward for the public interest programs (Park, 2005; Kim, 2006). However, KOBACO’S pricing mechanism has never been tested formally. For in- depth discussion, however, it is necessary to understand the Korean broadcast market structure and pricing mechanism. Market Structure and Pricing Mechanism The Korean terrestrial broadcast market is composed of three national broadcasters, ten local broadcasters networked with each other for national broadcasting, and eight independent broadcasters established to support religious and local programming. Each of the national and networked local broadcasters owns both TV and radio stations while the independent broadcasters Operate only radio stations,4 with the exception of iTV from 1997 to 20045. The three national broadcasters including KBS, MBC, and EBS are non-profit entities owned by govemment-created public institutions. KBS owns and operates 18 local stations and MBC has 19 local subsidiaries. EBS utilizes KBS facilities to transmit its signal nationally. Ten networked local broadcasters are all privately owned and one of them, SBS, is licensed to cover the Seoul region, produces and provides programs to the other nine local broadcasters while each produces its own local programming. Despite the gap in the number of local stations, the disadvantage of SBS in audience reach has been mostly offset by cable carriage of over-the-air " Whereas some public broadcasters have cable TV channels, they are not licensed for OTA TV broadcasting. Hence, OTA radio stations are included in my analysis. 5 iTV is the only independent broadcaster operating both over-the-air TV and radio stations. It covers lncheon, the western area of Gyounggi, and the Gangseogu district of Seoul, the capital of Korea. Its license had been suspended fi'om 2004 to 2007 due to failing to fulfill requirements set by the government. broadcasters. Cable penetration in Korea is approximately 80%. Regarding the number of channels, KBS has two channels, KBSl and KBSZ, while the other broadcasters have only one channel. To fund programming, KBSl levies an obligatory signal reception fee6 but the others, including KBSZ, MBC, SBS, EBS, and religious broadcasters, sell advertising time. For this reason, KBS] is more strictly regulated by the government than are other major broadcasters. KBSZ programming is similar to that of MBC and SBS. On the other hand, EBS, established exclusively for the TV delivery of educational content, receives 3% of the obligatory signal reception fee collected by KBS (The Order of Korea Broadcast Law, 2006, Clause 49). At the same time, EBS is supported by the Korea Broadcast Development Fund (KBDF) which the Korea Broadcast Commission (KBC) levies on commercial broadcasters. In 2004, approximately 15% of the fund (KW 17.3 of 116.2 billion) was spent to support EBS (KBC, 2005). In addition, EBS sells commercial time to advertisers through KOBACO, but its dependency on ad revenues is not as strong as that of the religious broadcasters due to explicit support from government. While the costs of KBS] and EBS have been supported explicitly via the obligatory signal reception fee (The Korea Broadcast Law, 2006, Clause 64) and the KBDF, it is a general interpretation that the losses of religious broadcasters have been implicitly subsidized by KOBACO through the packaged sale of their ad time with the major TV networks’ ad time. This implies that an important policy goal of diversity, arguably represented by religious programming, has been left in the hands of KOBACO 6 Clause 64 of the Korea Broadcast Law (2006) reads: “Anyone who owns a TV set to receive broadcasting signal should register its ownership of TV set and pay the signal reception fee to KBS.” However, referring to the clause 67 (2) of the same law, KBS has appointed Korean Electronic Power Company (KEPCO), the government owned monopoly, to collect the fee on behalf of KBS, which adjusts the fee with the permission of House of Representatives. which may have no means to support them other than to package commercial programs in the major TV networks with public interest programs in the religious broadcasters. Until recently, however, KOBACO did not distinguish public interest programs 7 or in constructing packages (Park and from commercial programs in calculating prices Lee, 2007, p. 338). Instead, KOBACO has set target revenues assumed to be sufficient for each broadcaster to sustain its operation. Broadcasters typically identified as subsidy recipients are religious broadcasters including BBS (Buddhism, FM Radio), F BBC (Christian, AM Radio), CBS (Christian, AM and FM Radios), PBC (Catholic, FM Radio), and WBC (Traditional Korean Religion, FM Radio). Despite the roles of EBS in delivering educational TV content to audience, it has not been mentioned in the literature as subsidized via packaged sale of ad slots. Exclusion of EBS from the list of subsidy recipient seems to be because EBS has other sources of subsidy such as the obligatory signal reception fee and the KBDF. EBS’S need for packaged sale of ads might not be as strong as religious broadcasters. On the other hand, the omission of independent local TV or radio stations such as iTV and SunnyFM covering Incheon area and KF M covering Suwon area from the list of presumed subsidy recipient seems to be attributed to their ownership structure. They were established by private companies with the purpose of profit maximization by delivering commercial content to the particular areas. In addition to these, public service obligations have been undertaken by the major TV networks as well. The Korea Broadcast Law (2006, Clause 50) requires the major TV networks to maintain the proportion of entertainment programming under 50% of their air time. The regulated networks are required to fill the rest of their airtime with educational 7 KOBACO introduced a public interest program index to its pricing formula in 2005. This gives 5% premium to the ad time in the designated public interest programs. and cultural programming. Hence, the public broadcasting services should be defined in a rather broader term in Korea to include the public service programming of the major TV networks as well as the religious broadcasters. Regarding sales Of broadcast ad time, four institutions are involved in ad time transactions: advertisers, ad agencies, KOBACO, and broadcasters (see figure 1). Advertisers buy ad time through ad agencies which in turn go to KOBACO to buy the time. KOBACO represents all the terrestrial TV and radio stations. But KOBACO organizations are divided into three subunits to represent one Of the three major TV networks, its radio subsidiary, and its associated minor broadcasters including religious and local broadcasters. In order for an ad agency to buy ad time in programs of three different major TV networks, it must buy it separately through each KOBACO subunit. An advertiser can work with one or more ad agencies to buy ad time. Two advertising sales markets exist in Korea, defined in terms of contract duration: upfront8 and scatter. The longer-term contracts (generally, longer than six months but shorter than a year) are made in the upfront market while the shorter-term contracts (generally, shorter than six months) are made in the scatter markets. The upfront market is held twice a year, April and October. Spots sold in the upfront market begin to air in May and November respectively. Among slots sold in the April upfront market, those contracted for greater than six months are excluded from sales in the October upfront market as they are still on the air. KOBACO generally sets a target of selling 50% of ad time inventory in the upfront market. Ad time not sold in the upfront 8 The term of “upfront” is used differently in Korea than in the US. Upfront in USA is associated with sales that take place substantially in advance of a television season, while scatter market sales can occur any time. However, the distinction between upfront and scatter in Korea is more related to contract duration than to timing. Ems—.0 —. Hnuumwomoaa waanoamrmcm wagon: mewumuuaosm >Q9 arm‘s—.3. WOw>OO 32:» \iii ir/ 2&2. HAS .9 ”iii.” WEE—E. /. :32. Hm9 Wane—n Fem—.3: N —k 1 M ’ IIIIIIIIIIII III-IIIIII‘ W 7:552. ow >=Ew=oo 2:552. 3. >=Eo=nm E: 13955 — .. m: wan—.3: N I . Eco—a >3 _ _ mom? 5.? Tennis >3 Fem—.3: >3 23:51» EU 56ng H5» Enos—.852: bang—.852: 10 indistinguishable from program ads. Technically, SB is separated from the post-program ads of the preceding program by a network ID announcement and from the pre-program ads of the following program by its title announcement. Five percent of program airtime is allowed for SB ads. Specifically, they are limited to two broadcasts an hour and four commercials per SB within 1.5 minutes. Radio can air SB commercials up to four times an hour. Each radio SB is allowed to have four commercials within 1.2 minutes. SB ad slots tend to have less value than program ads as audience Size decreases by the distance from a program, having the lowest point in the middle of the commercial break. Caption-type ads refer to text or still picture ads delivered during the announcement of network ID or program titles. This type of advertising is allowed up to six times an hour only on TV. Each ad should last less than ten seconds. The size of this type of advertisment cannot be bigger than a quarter of screen size. Finally, there are commercials associated with time announcements. Broadcasters announce the time at every hour or every half hour while inserting ads during the announcement. The Korea Broadcast Act (2006, Clause 59) limits this type of ad to not more than two an hour. Each can last no longer than ten seconds, ten times a day. In sum, maximum advertising time including program ads, SB ads, caption type ads, and ads associated with time announcements, comprises 16.7% of total program airtime. All individual advertising units are sold at prices determined by a formula published by KOBACO no matter whether they are sold in the upfront market or in the scatter market. Park and Lee (2007, pp. 337-338) describe the formula as follows (footnotes added): 11 Standard price for an advertising spot = required revenues per second of a network9 x length of an advertising spot10 x index of an expected audience rating of a programll x index of the program’s environment12 As presented above, the pricing formula for TV during these periods incorporates several factors such as spot length, expected audience rating, and market environment. Expected audience rating is a product of genre and past performance of daypart,l3 time of day divided into four categories reflecting the size of overall television audience predicted for those times (see figure 3). Scholars accept these factors as important determinants of ad time prices (Fournier and Martin, 1983; Park, 1996) and they are applied widely in the industry. Prices set by the formula become the bases from which rate adjustments are calculated. 9 Required revenues per second for each network are calculated by dividing total required revenues for a network by its total commercial time allowed. '0 The length of an advertising spot varies depending on demand from advertisers. However, 15 seconds are most common for TV commercials and 20 seconds for radio commercials. ” Expected audience rating of a program is a product of the expected audience rating of a daypart and an index of genre of the program. The first term represents the simple average of long-term (past two years) and short-term (past 3 months) audience ratings of a daypart in each network. The multiplier index for a genre reflects the relative average of past ratings in a time period for different genres. The genre is assigned one of seven index levels. Regardless of the network, drama/movie/entertainment receives the highest multiplier index while composites and unclasifieds receive the lowest. Expected audience rating is then transformed into the multiplier index. '2 The index of expected audience rating of a program, in turn, is multiplied by the index of market environment, which represents the demand/supply ratio (D/S ratio) for advertising spots of a specific program. The D/S ratio assigned one of 13 index levels within a range of 150% to 40% where 150% indicates that demand for ad time is 1.5 times of its supply while 40% indicates that demand for ad time is 40% of its supply. While all other factors considered are not program specific, the index of market environment represents expectations of the performance of a particular program. The D/S ratio is influenced by the advertisers’ preferences for a particular program. What advertisers consider most is the actual audience rating of the program. Thus, this factor reflects the gap between audience ratings calculated by the formula and those anticipated by advertisers at contract time. In this sense, the index provides feedback from the audience rating of a program to its net profits, and therefore creates incentives for the networks to invest in program production budgets. In reality, the ratio is subjectively determined by KOBACO sales personnel using intuitive calls based on years of experience. '3 A television day is divided into 4 dayparts based on the size of the overall audience. Dayparts are categorized as SA, A, B, and C in TV depending on advertisers’ preference, where daypart SA is equivalent to prime time in the US broadcasting system, while daypart C is the time slot in the early morning and late night and is least desirable. Daypart A is in the early or late fringes of daypart SA while daypart B is between daypart A and C (KOBACO, 2006). Radio divides dayparts into three: A, B, and C in order of most valued to least valued. l2 ~3de w. 5368.? 3.. H< 35 ”name wanna—um H< €8.33. 31.8 ‘ Sue . 8% 3:5 5:5 . 8 ,. 8. N98,. was: A .N............_.. . A... . c 1%. .._ O > w > m> > w n mans—dew. . 3.25 . , as... as A , as _ .. _. ..wa..‘e..__._ No.8: as Fe. ‘ O > m> > w O m==Q~< ) . Sam 33 ‘ ewe \\\\\ w m> > w O ”an? iaarawwgaarga as: E... _ as ..__....s.‘ ...,. s... s 6 w l3 Examples of such adjustments include preemption”, designation for ad placement15 , seasonal premiums or discounts”, and discounts for venture firms eligible for daytime advertising spots at around 30% of formula prices (KOBACO, 2006). The pricing formula used for TV block ads is similar to that for TV program ads but uses different indexing factors. The formula for radio ad slots is basically the same except that the audience rating factor is excluded from the formula because radio audience ratings are not reported as comprehensively as or as regularly as TV ratings. While TV audience ratings are reported daily by two well-known audience research companies (Nielsen and TNS), there is no formal audience research company for radio programs. KOBACO subscribes to HRC radio audience reports published quarterly. To fill the gap, research companies such as Lee’s PR and ACR irregularly survey radio audiences at the request of broadcasters, advertisers, or other interest groups (Park, 2005). Due to the lack of organizational support and low reliability, radio audience ratings have been disregarded in KOBACO’S ad pricing formula (Kim, 1999). It has been known that there is no volume discount in practice, or published on the rate cards. This fact indicates that calculated spot prices are applied to spots purchased in the package. Informal interviews with advertisers reveal that package price is simply the ‘4 Preemption offers advertisers the right to acquire certain previously sold ad spots if they pay higher prices than the previous buyers. Preemptible spots are generally announced in advance. All spots in preemptible programs are sold only on a preemption basis. For example, if 24 spots are available for a 60- minute program, all 24 spots are available for preemption if any are. Preemption contracts generally last for a month but are guaranteed up to six months if the offered prices are higher than thrice the formula price (KOBACO, 2007). '5 Advertisers can designate the location of ad slots purchased at extra costs. Concerning the placement of the commercial, a slot is selected from the slots available before or after programs (Note that ad messages cannot be inserted within a program in Korea.) As audience size tends to decrease closer to the middle of the commercial break, advertisers generally prefer placement closer to a program. ‘6 The formula prices are adjusted seasonally to take into account the seasonal fluctuations of audience size and demand for ad time. At least, 10% of the formula prices are discounted for the purchase of ad time during the off-peak season while premiums of around 10% of are applied during peak season. In 2006, peak season included September, October, May, and June while off-peak season included July, August, January, and February. 14 sum of individual spot prices in a package. Many industry observers believe that the formula itself is biased downward for programs with high commercial value and upwards for programs with low commercial value. If, as alleged, prices on rate cards were distorted, it is natural for the previous studies not to find empirical evidence of price efficiency in the broadcast advertising market as presented in the literature review. Rationale for the Study These pricing practices raise two interrelated issues to be investigated. One is that KOBACO cannot know how well its posted prices compare to implicit market prices and no one knows whether KOBACO has approximated market prices well. This study tests if there are distortions built into their pricing formula, more specifically, whether the factors they employ to determine prices appropriately reflect true market values. The second issue is whether there are subsidy flows from other programs to programs favored by regulators. Selling ad time in favored programs in a package with other programs’ ad time and setting prices for the other programs’ ad units lower than their market values while selling time in favored programs at above market rates is the mechanism whereby subsidies could be implemented. Because ad units are sold in packages, market prices for ad time in different programs from different providers cannot be observed directly. If package prices are determined by market forces, however, we can assume market values for the ad units comprising packages are implicit in the package price. Given the lack of empirical knowledge of implicit market prices, regulatory bodies must sit as puzzled arbiters of conflicting claims made by various private and public interest groups. For example, Park 15 and Lee (2007) argue that the current KOBACO pricing system has been improved to reflect the market values of ad time, while others claim that the distortion is still significant. Expanding the pricing issues to the policy concerns, some (i.e., Park, 2004; J eon, 2004) state that policy change from monopoly to competition will cause a Significant price increase for major networks and financial distress for public broadcasters while Jung (2005) and others claim that there will be little price impact from regulatory regime change. Depending on the methods employed, predictions of likely price increases range from 10% (Jung, 2005) to 400% (Park, 2004) for the major networks. In either case, however, previous studies have substantial shortcomings. Studies using published rate cards (e. g., Lee, 1995; 1997; 2004; Kim and Lee, 2004; Park, 2004) are flawed because advertising spots are sold in packages, and there is no way to know whether advertisers value the spots in the packages at their published rates. Even the study employing a survey method to estimate advertisers’ willingness to pay (Jung, 2005) contains limitations: (1) surveys may systematically under-estimate market prices as advertisers report their willingness to pay more conservatively in response to a survey than their behavior in the market would indicate (Monroe, 1990, p. 107—112); at the same time, (2) translating survey results into demand and supply curves requires a number of a priori assumptions such as frequency of advertising purchase by advertisers and the number of spots supplied to these survey participants. The assumptions tend to render the results arbitrary and unreliable. Hence, this study develops a model to estimate implicit market prices for Korean broadcast advertising time using actual transaction data, which enables estimation of the 16 level of price distortion under the KOBACO system and of the cross-subsidies alleged to exist due to packaging practices. Implicit market prices are estimated using the hedonic approach where price is determined by characteristics of component advertising time. Factors assumed to influence market value include audience size, demographic composition, and daypart (F oumier and Martin, 1983; Napoli, 2003; Wildman, 2003). The empirical challenge of this study is to find and construct market valuations of ad spots in the Korean broadcast market where published rate cards may not reflect market values. Drawing on bundling theory see c. g. Venkatesh and Kamakura, 2003; Adams and Yellen, 1976; Schmalensee, 1984; McAfee, McMillan, and Whinston, 1989; the proposed model assumes that package prices reflect market values for the ad spots although the individual spot prices may not. This assumption implies that a buyer’s reservation price for the package is equal to the sum of his or her separate reservation prices for component ad spots. However, actual package data were not available for the study. Therefore, composite package prices were constructed from the ad budgets spent by an advertiser on a network through a particular ad agency. Constructed composite packages for individual advertisers were comprised of all ad time all packages purchased by an advertiser through a specific ad agency. Composite package prices were measured as each advertiser’s purchases from the agencies. This approach reflects the actual transaction practices where individual packages purchased. by advertisers did not mix ad slots across agencies or networks. This dissertation is organized as follows: Chapter I introduces the background and goals for the study. Chapter II reviews related literature. First, the studies of prices for Korea broadcast advertising time are reviewed. Second, the theoretical and empirical 17 aspects of the hedonic model are reviewed to develop the model for this study. Third, three different viewpoints on the valuation of packages are reviewed briefly from the perspective of the bundling literature. Chapter III describes a hedonic model developed to estimate implicit market prices for Korean broadcast advertising time. Chapter IV describes the data and methodologies for measuring individual variables. Chapter V reports regression results. Chapter VI discusses the dissertation’s contributions and limitations and its implications for future studies. 18 CHAPTER 2 LITERATURE REVIEW Studies on Prices for Korean Broadcast Advertising Time The transaction system for Korean broadcast advertising time has been studied mostly from the perspective of policy change (Kim, 2004; Kim, 2006; Yang, 2007; Jung, 2007). These studies equate the monopoly transaction system with inefficient ad time pricing in the market and they assume that the most popular programs are under-priced to sell protected types of programs at higher prices than their market values. However, these assumptions have never been empirically tested with sufficient evidence. Nevertheless, studies undertaken by Lee (1995; 1997; 2004) and Jung (2005) Should be acknowledged for their contributions to the understanding of the Korean broadcast ad pricing system and exposition of the level of possible price distortion, which also is a goal of this dissertation. Lee has conducted several empirical studies to investigate relationships between broadcast ad time prices and program performance. In a study published in 1995, he analyzed 391 television programs aired in the first half of 1995 and found that ad time prices were not determined by program performance. For example, while ad time prices for the programs delivered during the same daypart were fixed at KW 4,788,000 in a particular week of May 1995, audience ratings ranged from 5.8% to 32.5% for these programs. In an extended study of the four major media, TV, radio, newspapers and magazines, Lee (1997) stated that the study confirmed his previous findings that Korean 19 broadcast ad time prices are not well explained by audience ratings. In 2004, the author replicated his 1995 study to evaluate the reform of KOBACO’S pricing system in 2000 when the “global standard (GS)” ad pricing system was introduced with the goal of setting prices based on audience ratings, market environment, and required ad revenues for the networks. The author concluded that audience ratings were still not reasonably taken into account for ad time pricing. His conclusion was based on the facts that only 55% of price variation was explained by audience ratings and that comparative ratios of average price to average audience rating were inconsistent across the dayparts and networks. However, Lee does not explain why he sees 55%, the variation in rate card price explained by audience seconds, as too low to interpret KOBACO prices as efficient. Generally, ad time prices are not fully explained by audience seconds, as uncertainties are involved with the prediction of audience ratings at the point of contract (F oumier and Martin, 1983). Only 57% of USA ad time prices, believed to be efficient market prices, was explained by the number of viewers, the number of viewing males aged 18-49, and the number of viewing females aged 18-49 exposed to the 30-second spot (Fournier and Martin, 1983, p.49). More fundamentally, however, studies such as Lee’s (1995; 1997; 2004) using published rate cards are flawed because advertising spots are sold in packages, and whether advertisers value spots in the packages at their published rates is indetenninable. His studies have been cited without criticism in subsequent discussions of KOBACO’S pricing system (e.g., Kim and Lee, 2004). While attempts are made by Lee (1995; 1997; 2004) to find evidence for inefficient ad time pricing in the Korean broadcast ad market, others explain causes and 20 effects of inefficient ad time pricing. For example, Kim, et a1. (2003) argued that, due to packaging practices, KOBACO’S pricing system has caused loss of social surplus in both types of programs, subsidizing and subsidized. Kim and Lee (2004) also claim that investment efficiency and program quality cannot be improved until a strong relationship is established among investment, audience rating, and return on program production. Studies indicating packaging practices as a reason for price distortion include Choi (2005), Jeon (2004) and Jung (2005). Especially, Park and Lee (2007), clearly posit the existence of a packaging transaction system in Korean broadcast ad time market. In the paper, the authors argue that although there is a tendency for prices not to be determined in the market, demand and supply are cleared in the market through the packaging practice where ad time in high valued programs is sold in combination with ad time in low valued programs. Accepting KOBACO’S packaging practice as a fact, Jung (2005) attempts to estimate the implicit market prices for Korean broadcast advertising time. In a survey of the 100 largest advertising agencies, the author found that current, posted prices deviated significantly from willingness to pay for the programs showing the equivalent performance. He found that willingness to pay for programs with a 25% audience rating, typical for popular primetime dramas assigned to daypart SA, was KW 20-million, which was 26% higher than MBC’S published price, 34% higher than SBS’S published price, and 42% higher than KBS’s published price. As for prices for ad time in daypart A, estimated market prices are KW 8-million for MBC and KW 7-million for SBS and for KBS. These estimates are higher than the published price by 22%, 25%, and 10%, respectively. On the other hand, willingness to pay for ad time in dayparts B and C was 21 estimated to be lower than the published prices by 13% to 23% depending on the networks. On average, ad revenue was estimated to increase by 14.8%. The author also estimated implicit market prices for religious broadcasting while admitting limitations of prediction. Employing the same method used in the prediction of TV ad slots, he claimed that religious broadcasters’ revenues would decrease by at least two thirds. The findings, if the employed methodology is deemed reasonable, provide evidence of the existence of price distortions caused by packaging practices. Otherwise, it is difficult to explain KOBACO’S charging lower prices than those advertisers are willing to pay for time in popular programs. Also, it would be impossible for KOBACO to sell time in dyparts B and C as well as in the religious broadcaster’s programs at prices above what advertisers would be willing to pay if purchasing time in these programs on a stand- alone basis. Nonetheless, the survey method using advertisers’ self-stated willingness to pay (Jung, 2005) has the limitation that advertisers tend to report their willingness to pay more conservatively in surveys than in the market (Monroe, 1990, p. 107—112). Moreover, assumptions made for the study contain serious limitations. Jung (2005) administered a survey to the 100 largest advertisers and drew a demand curve by quoting the willingness to pay indicated by 82 subjects who returned questionnaires. Then he adjusted the supply for the ad time in each daypart referring to the average program hour, the number of respondents, and the probability that the 100 largest advertisers would buy more than one ad slot and that other advertisers would purchase the particular ad slot. The study estimated prices for the ad time in daypart SA by assuming that the supply for the ad time on a one-hour program was 24, the total number of ad slots allowed for a one hour 22 program (24 = 10% of 60 minutes / 15 seconds). However, the study increased the supply of ad slots to 42 in daypart A, to 72 in daypart B, and to 72 in daypart C, assuming an increasing probability that the 100 largest advertisers would buy more than one ad slot and that advertisers would also purchase the particular ad time. But he did not provide any supporting arguments why these particular assumptions are employed. Small changes in these assumptions could produce significant changes in the estimated market price. Hence, it is meaningful to explore implicit market prices using actual transaction data reflecting advertisers’ purchasing patterns. Consumers, including advertisers, basically react to the market based on their demands for products and substitutes for them. In the advertising market, it is reasonable to assume that advertisers would pay no more for ad time than its value to them as buyers are well-informed by advertising agencies about prices and substitute products. Even when ad time is sold in packages due to regulation or for other reasons, there should be indicators that reflect market demand. Hence, the present study proposes a hedonic model to investigate the following research questions: RQl. What are the implicit market prices for advertising Spots? RQ2. Are there cross-subsidies flowing from some types of programs to other types of program? RQ3. If subsidies exist, how large are they? 23 Hedonic Price Estimation Studies and Advertising Time Prices Significant research has been conducted to estimate ad time prices for different media. Especially, the hedonic approach has provided an empirical framework for studies assessing the relationship between ad time prices and the characteristics of media audiences upon which ad prices are based (Fisher, McGowan, and Evans, 1980; Fournier and Martin, 1983; Waterman and Yan, 1999; Koschat and Putsis, 2002). In the hedonic model, measures of audience demographics have been treated in the same way product attributes are treated in studies of demand for other products and services. This logic is stated most explicitly, perhaps, by Fournier and Martin (1983) in their article on the price of station-sold time in local television markets, who characterize their econometric model as a hedonic model. The theoretical exploration of the relationship between product characteristics and the demand for a product was pioneered by Lancaster (1966, 1971). Different from traditional economic theory of consumer demand, the author assumes that utility or satisfaction from goods is derived from product characteristics, not from the product itself (Ratchford, 1975). While it has been acknowledged as a “revolutionary” change of perspective, Lancaster's assumption of infinite divisibility makes his model difficult to apply to some goods, especially, to “expensive and infrequently purchased goods” (Ratchford, 1975, p.71). A rather convenient solution for empirical modeling was developed by Rosen (1974) following initial modeling by Griliches (1971). Rosen assumes that “the various goods sold in a market are indivisible, and that a consumer buys only one brand of the goods per year” (Ratchford, 1975, p.71). Hedonic price functions suggested by Rosen have been acknowledged as “empirical summaries Of the 24 relationship between the prices and the characteristics of goods sold in differentiated product markets” (Pakes, 2003, p. 1580). While a series of papers investigated the theoretical issues of the relationship between characteristics and prices for the differentiated products (Rosen, 1974, Epple, 1987, Anderson et al., 1992, Berry et al. 1995; F eenstra, 1993; Pakes, 2003), hedonic analysis achieved its popularity by providing a convenient empirical framework for industry members and researchers. To design an empirical model based on the hedonic approach, it is therefore important to define characteristics correctly, although, as Lancaster himself admits (1971, Ch. 9-10), there may be “severe difficulties in defining characteristics operationally”. In the context of ad time pricing, Webster and Lichty (1991) suggest numerous factors affecting broadcasts’ advertising revenues. Included are audience Size, demographic composition, and daypart. Gensch and Ranganathan (1974) found significant mean differences among demographic groups in their preferences for program types and it is generally believed that advertisers value age group 18-49 more than others (CAB, 1989, p 22; Barnes, 1990, p. 32). Napoli (2003) also asserts that firms advertising products for a target group aged 18-49 pay relatively higher prices for spots reaching a higher proportion of viewers in the category. Fournier & Martin (1983) and Park (1996) also assumed that the market equilibrium value of audiences exposed to commercial messages will differ between age groups and found evidence supporting this assumption. Even among the same age group, however, a study by Koschat and Putsis (2002, p. 267) found that increasing the fraction of women has a negative effect on the price. This indicates that advertisers prefer male audience members to female audience 25 members and therefore a relative increase in the female proportion of the audience will reduce price after controlling for other factors. Fournier and Martin, (1984, p. 49) also found that the fraction of an audience comprised of women aged 19-49 had smaller effect on price than the fraction of men aged 19-49. Hence, including demographic characteristics of audience, such as age and gender, should improve the accuracy of predictions of ad time prices. However, the effects of audience segments on prices for broadcast ad time can differ depending on cultural context. Difference in viewing patterns among demographic groups should be larger in countries where individualism dominates than in countries where family-oriented norms dominate. If all family members watch the same programs, then demographic segmentation does not have much impact on in ad time prices. In an empirical study, Fisher, McGowan, and Evans (1980) also found that daypart has an effect on audience revenues in the broadcasting programs. This seems to be a reflection of reality (Waterman and Yan, 2001; Lee, 2004). In the context of the Korean broadcast market, KOBACO defines daypart as “a central factor determining prices for the broadcast ad time” as it “reflects life style and size of audience in specific hours of broadcasting” (Lee, 2004). Currently, the broadcast day in Korea are divided into four parts for TV: SA (8pm-11pm), A (8:30am-9z30am, 7:00pm-8z00pm, 11pm- midnight), B (7:00am-8:30am, 9:30am-noon, 5:00pm-7z00pm, midnight-0:30am), and C (noon-5:00pm, 0:30am-7z00am). The time slots mentioned above apply to weekdays. Weekends have different time schedules. '7 Radio divides its broadcast day into three ‘7 On Saturday it is SA (7:00pm-11pm), A (8:30am-9z30am, 5:00pm-7:00pm, llpm-122pm), B(7:00am- 8:30am, 9:30am-5:00pm), C (0:30am-7200am); On Sunday it is SA (7:00pm-1 1:30pm), A (8:30am-7zpm, 11:30pm-midnight), B (7:30am-8z30am, midnight-0:30am), C (0:30am-7z30am) 26 components regardless Of day Of the week: A (7am-4pm, 7pm-9pm), B (6am-7am, 4pm- 6pm, 9pm-midnight), and C (midnight-6am). While audience size and dayparts tend to co-vary, they have been considered as different variables. While dayparts are fixed before contracts are made, knowing the exact size and the composition of the subset of an audience composed of an advertisers’ potential customers is extremely difficult or impossible as no one in the industry can make perfect predictions. Even the viewers themselves do not know exactly what they will watch or listen to before they actually choose (N apoli, 2003). Furthermore, even afier media consumption is complete, audience research firms, and thus media operators and advertisers, do not know the exact composition of an audience due to statistical problems of audience measurement. The uncertainty involved in estimating audience size affects pricing decisions and thus the revenues of a media firm. As such, daypart has merit in determining ad time prices but does not incorporate the unique characteristics of programs. The performance of a program differs depending on genre, plot, scenario, director, actor/actress, and many other factors even within the same daypart. Despite difficulty in prediction, audience rating captures the variance which is not captured by daypart. Although the hedonic model is acknowledged to be a convenient method to estimate valuation of ad time attributes, its theoretical and methodological weaknesses have been addressed by many researchers. Especially, Garrod and Willis (1999) point out that the hedonic model only can estimate consumption benefits, while Garrod’s previous work (1994) addresses more analytical problems such as omissions of important characteristics and incorrect mathematical specification of the model. However, 27 Vanslembrouck et al. (2003, p.19) claim these limitations can be taken into account adequately. Referring to Palrnquist (1991) and Freeman (1993), they argue that “ignoring the producer side does not create theoretical or econometric problems” when the focus is on buyers’ valuation of product characteristics. This is applicable to the Korean broadcast ad time market as the supply of the ad slots is fixed by regulation. This implies that all advertisers make their profit-maximizing choices given the prices of ad time (Wildman, 2003) as prices reflect the existing market given the supply of ad time and its characteristics. Despite the abundance of empirical studies utilizing the hedonic method, few studies have been conducted to explore empirically the implicit market prices for a bundle of products. However, the pervasive use of bundling strategy in reality to sell products, specifically ad spots (Park, 2004; Tankard and Henry, 1993), increases the need to explore implicit market prices for component products sold in bundles. Meeting the need with the hedonic approach is the central focus of this study. Closest to the present study is research conducted by Koschat and Putsis (2002) who interpret the advertising space as a product that bundles different audience demographics and attempts to find implicit market prices for each unbundled (targeted) audience, by decomposing the value of each demographic group from the bundled audience. In a strict sense, however, every hedonic model for advertising price has a bundling component in it. For example, Fournier and Martin (1983) looked at bundled prices Of audience demographics, since they viewed the price for a television spot as the sum of the values of the audience segments sold. However, Koschat and Putsis (2002) advance the logic to estimate the 28 implicit market prices for component demographics. Their argument is Stunmarized in the following statement (Koschat and Putsis, 2002, p. 264): Because market price is expressed as a function of a product’s characteristics, the availability of objective measures of a product’s characteristics combined with Observations on market prices enables a researcher to estimate the implicit price of each characteristic. Therefore, market price can be broken down into the components that correspond to the characteristics of the product. However, the present study differs from the work by Koschat and Putsis (2002) in terms of research purpose and methods employed: they explored the bundling of audience segments, not bundling of different ad units. They intended to explore networks’ revenues expected to be generated by the targeting strategy given that current spot prices are the market price for an audience given its demographic composition. This study, however, explores implicit market prices for the individual ad spot comprising a package where package prices, defined as the ad budgets spent by an advertiser through a particular ad agency in a network, are assumed to reflect market values. Despite the lack of literature exploring prices for the bundled ad spots from the hedonic perspective, the prior studies using the hedonic model provide a theoretical and empirical foundation for the present study. In order to use the hedonic approach, it is critical to have market prices as a dependent variable in the model. However, published rate cards in the Korean broadcast ad market are known not to reflect market values. Hence, it is important to find an alternative variable reflecting market values for advertising slots. The proposed model assumes that package prices are the sums of true market values for each component ad slot in the package regardless of prices on the published rate card. This is an especially salient issue for this study because, if the package price is the sum of market prices for the component programs, it should respond to the sum of their quality characteristics as 29 well. While the mathematical presentation of this argument is reserved for Chapter III, the bundling literature provides theoretical support for the rationale. Implicit Market Prices for the Bundled Products Regarding relationships between the value of the bundle and the stand-alone values of the components, bundling literature, Specifically the theory of reservation prices, suggests three different possibilities: super-additive, sub-additive, and strictly-additive (V enkatesh and Kamakura, 2003). Super-additivity occurs when a consumer’s valuation for a bundle is larger than the sum of the stand-alone values for the component products, while sub-additivity describes the opposite condition where a consumer’s valuation is smaller than the sum of the stand-alone values for the component products. Strict- additivity refers to the middle position where a consumer’s valuation for the bundle is equal to the sum of his or her separate valuations for the component products. The difference in the consumer’s valuation for the bundle compared to the stand- alone products is attributed to the unique relationships among bundled products. Supper- additivity arises when products complement each other in the bundle while sub-additivity arises when products substitute for each other in the bundle as Venkatesh and Kamakura (2003) explain: When products are complements, a consumer’s reservation price for the bundle is superadditive in those for the component products. Guiltinan (1987) suggests that complementarity arises because of search economies (e. g., oil and filter changes at the same gas station), enhanced customer satisfaction (e.g., Ski rental accompanied by a lessons package), and improved total image (e.g., offering lawn care and shrub care services). Alternatively, when the products are substitutes, a consumer’s reservation price for the bundle would be subadditive in those for the components. This is likely when the products offer (some) overlapping benefits (e. g., “Coke” and “Pepsi”) or when they compete for similar resources such as a consumer’s time. 30 On the other hand, strict additivity arises when the component products are independent of each other (V enkatesh and Kamakura, 2003). Venkatesh and Kamakura (2003) conclude that many bundling articles develop their arguments based on this strict additivity assumption after surveying key papers including Adams and Yellen (1976), Schmalensee (1984), McAfee, McMillan, and Whinston (1989). The empirical analysis is Simplified considerably by strict additivity. Hence, this paper will follow convention and rely on the strict additivity assumption. 31 CHAPTER 3 EMPIRICAL MODEL OF IMPLICIT MARKET PRICES Estimation of Implicit Market Prices A hedonic model is developed to predict implicit market prices on the basis of audience demographics and other characteristics of programs to which advertising messages are attached. Past hedonic studies have suggested many factors affecting rates that broadcast television networks and stations charge advertisers (Webster and Lichty, 1991; Fournier and Martin, 1983; Levin, 1980; Poltrack, 1983; Wirth and Bloch, 1985). Among variables found to affect ad time prices, the proposed model includes audience size, demographic composition, and daypart as independent variables. While the proposed model is constructed drawing upon previous studies, it is not relevant to directly apply previous approaches to the Korean market as there is no evidence that published rate cards approximate market prices (Lee, 1995; 1997; 2004; Kim and Lee, 2004; Jung, 2005). Hence, it is important to find a reasonable, alternative variable that reflects market price. A model is constructed based on the assumption that the package price (Pi) is the market price for the bundle Of ad units in package i (P1. = pl x xi" + p2 x x; + p3 x x9"), where p j and x j represent market values and ad units sold respectively for advertising units in program j , for j = 1, 2, 3, , J where J is the number of programs in the bundle as well as the last program listed. This assumption is reasonable because advertisers would not pay more than their willingness to pay for the packaged products. According to Venkatesh and Mahajan 32 (1993), an individual who expects to buy J products is likely to buy the bundled products if the bundled price (P,- ) or the mean price per product (P,- /J ) is less than or equal to his/her total or mean reservation price. Bundling articles commonly assume that a consumer’s reservation price for the bundle is equal to the sum of his or her separate reservation prices for the component products. In the context of the Korean broadcast ad market, the package price is the sum of the products of the prices set by KOBACO and the corresponding quantities of ad units in the package (P,- = kl x xi + k2 x x3 + k3 x x; + ). The necessary equality of the two sums of prices and quantities can be represented as follows: Pi =p1xxli+p2 xx; +p3 xp§.+..=k1xx1i+k2 xx; +k3 xx; +... (3.1) where KOBACO set prices (kl , k2 , k3 ) can differ from their corresponding implicit market values ( p1, p2 , p3 ...) if KOBACO’S prices are determined by the factors other than market value. If the package price is the sum of market prices for the ad units in the component programs indexed by j , it should respond to the sum of their quality characteristics. To illustrate the argument, a simple formula is created where the market price for a spot in program j in package ( p ij ) is a linear fimction of audience size (A (j) and a dummy for the program’s daypart (Dij ). Audience size is the total number of viewers watching a particular program while dummies for daypart indicate the categorical variables for the dayparts, SA, A, B, and C where daypart B is treated as a base case. Thus, we have: A SA A C pi]. =a+,6’1Aij +,6sz- +,6’3Dij +,B4Dij (3.2) 33 If individual market prices are summed up across ad units in a package, the left side of the equation becomes the package price (Pi) and the right side of the function becomes the sum of the products of the coefficients and the independent variables which now are the sum of the viewing audiences (ZAz‘j ) and the sum of ad spots in each J daypart (2 D5” , 2 D51, 2 D5 ) in the package. The sum of ad spots in each daypart is J J J the total number of ad spots the advertiser purchased in each daypart, which could include multiple spots in some programs. As the sum of dummy values in each daypart becomes the number of ad spots in each daypart, the notation of the sum of daypart dummy, “ 2D!" ”, is transformed into the number of ad spots in each daypart, “ Z N ij ”, J J to minimize confusion. While the function with dummy variables (3.2) has the base case as daypart B and the coefficient for each dummy is interpreted as each daypart’s incremental effect relative to the base case, an equation with Z N ij does not need to J have a base case and the coefficients for Z N 5A ,ZNJI , ZNUB , 2N5 indicates their 1' J J J own effects on the package price. Thus, interpretation of the constant term (or ) also changes. While or in equation (3.2) represents the original intercept and includes the effect of the base case, the corresponding term (a) in an equation with Z N ij J represents the old intercept term without the effect of daypart B. (a) is thus replaced by ((51):: N; ). Thus, we have: 1 34 21:19,]- =(-Z;NiJT- +IB1§J,:Az'j +51%:NgA +522;le B C ”32% ”42% :1), (3.3) J J However, reality is more complex than this. Advertisers buy advertising spots reflecting demographic characteristics of consumers of their products and the effects of spot duration on consumer behavior. Hence, the preferred specification is where P, is the m2049 Air package price, is the number of viewing males aged 20-49 in the package, A If 2049 is the number of viewing women aged 20-49 in the package, and A (JO-”7” is the number of male and female audience aged other than 20-49 weighted by the length Of ad spots in the package. For simplicity, the number of viewers weighted by the spot seconds is called audience seconds. Total audience seconds are calculated by multiplying the ad time purchased in each program times the size the program's audience size and then summing the resulting products over all programs in the package. N 5A is the number of ad spots in dapyart SA, Nil/.1 is the ntunber of ad spots in daypart A, N 15'} is the number of ad Spots in daypart B, N If is the number of ad spots in daypart C weighted by the lengths of individual ad spots in the package. The weighted number of ad spots is called the number Of ad units. Hence, 2 N ”T is now the total number of ad units in the package. j The relationship can be represented as follows: _ ‘ T \ 2722049 f2049 other 13.—aim]. +fl1;.4,j +62%:Aij 1563;.40. J 35 (3.4) SA A B C +61;Nij +52;sz +53;Nij +64%:Nij +eij Where P- is a nonnegative dependent variable and e -- are the sum of independent I 11 random errors with a mean of zero. Reality adds more complexity to the model. Packages are constructed with various types of ad slots including program ad slots and block ad slots for the major TV networks (KBS-TV, MBC-TV, and SBS-TV) as well as for the subsidized radio broadcasters (FEBC-AM, CBS-AM, CBS-FM, PBC-FM, WBS-FM). Hence, the product should be specified further by identifying TV-program ads, TV-block ads, radio-program ads, and radio block ads where radio indicates those subsidized. In the final model, the package price (Pi) is modeled as a function of TV audience seconds for each ad type and PG PGf2049 PG each demographic specification( A ”’2049 , A , A 01h” ; Z]: TVij Z TVij 21:. TV!)- ZTV AB Lm2049 ’ZTV A BLf2049 ,ZAfVij LOW” ,where superscript “ PG ” and “ BL ” represent ”’7 VJ program ads and block ads respectively), radio audience seconds described by the ad . PG 7 PGf2049 PG 1 BL 20 9 types and demographics ( A ”171-049 , A __ , A .. 0’ 7"r; A ”m 4 , BLf2049 BL (h) - - PGSA EAR” ,2 ARHO " ), number of TV ad units In each daypart (Z NTV.. , J ’ J ’J j U PG ZNT (:A’ENTVy i3 ZNTVif ZNfVSA ZNTV; ’ZNTVf ZNTVS ),and PC PC number of radio ad units in each daypart (2 NR] A ,Z NR1] B ,Z N; 0": ,2 N11; A, 36 BL B BLC . . . Z N R.. , Z N R.. ). There 15 no commonly accepted, complete or accurate Information J' ’1 J ’1 on radio audience size available. Hence, the audience second variables related to the radio ad time are removed from the proposed model. A complete listing of the variables with their definitions appears in Table 1.The model can be represented as follows: — PG 130 _. T ‘PC5n2049 .f2049 cnher Pi "aZNij +IBIZATV1“ +flQZATV~ +fl3ZATV“ J J 1 J '1 J ’1 +,B ZABLm2049 +16 XABLf2049 "I'fl ZABLot/ter 4 TV,” 5 , TV.. 6 TV.. J IJ IJ J J J PG PG PG PG SA A B C +512NTVIH +522:an +53ZNTV__ +54ZNTV” J U U U J J J J BL BL BL BL SA A B C “552qu 4462an +67ZNTV” +582NTVH J ’J J ’1 J ’1 J ’1 PGA PGB PGC +692NR” +5IOZNR” “SHEA/R.- J ” J ’1 J ’1 BLA BLB BLC +612;NRIJ mug“? MHZ/1%,] +ey. (3.5) 37 Table 1. Variables and Data Variable Definition Source P2 ‘k' 0 P"‘ : S f KOBACO .‘ t f ‘d‘l‘fe‘e tzd 1' ":h' ."d b ‘d t th‘ Uh ' d :0 Pubr 1c age rice um 0 so prrccs or 1 crcn‘ 1 Irme lel asc y a vcr rser a rout, a tgency b KOBACO from network ( ’) ZAT vzzdmg Total TV audience seconds for the male 20—49 group revealed to program ads in a package abt‘ The Korea Stigfiglcgearbook 2004 PG . f 4049 . . . . KOBACO A . , 4.. . . . 7_(o. -. fl) 0.. ‘2"‘0 . .. s 2; Tvabq Total TV audience seconds for the female 20 4) group rcVe Ilcd to program ads In a p tckage abc The Korea Statistlcal Yearbook 2004 A other 2 I ,7 .. .‘ I .,‘. I 9_ O, -, ”t _OII( I .' I "'0 _ KOBACO, g: T (1!ch Tot 11 TV audience seconds for other than male/female -0 49 grouI reve fled to progr rm ads In a package abc The Korea Statistical Yearbook 2004 AB Lm2049 I I . I . . . . I 7 _ O “I 2 . . 2 I I 0 . KOBACO, ZTV Tvabq' Total TV audrencc seconds for the male 20 49 group revelled to block Ids 1n 1 package abc The Korea Statistical Yearbook 2004 Lf2049 I I -. ,~ I 7 _ II , . . .- I .., . KOBACO, gAii/Z’JCJ Total TV audience seconds for the female 20 49 group rev.aled to block ads In a package abc The Korea Statistical Yearbook 2004 AB L'othel I 4 . I I - I a _ 0, _ I . 7 I . - I I I a . KOBACO, ZTV Vabcj Total TV audience seconds for other than male/female 20 49 t,Ioup revealed to block ads In a package abc The Korea Statistical Yearbook 2004 Z N:l:j Total number Of ad units among programs ( j ) in a package abc KOBACO ZN TVGS 17A Total number of TV program ad units in daypart SA among programs ( j) in a package abc KOBACO a cj Z NTVA b Total number of TV program ad units in daypart A among programs (j) in a package abc KOBACO a Cj Z NTVB b Total number of TV program ad units in daypart B among programs (j) in a package abc KOBACO a Cj Z NTV Wabcj Total number of TV program ad units in daypart C among programs (1) in a package “/99 KOBACO 21(13ijthch Total number Of TV block ad units in daypart SA among programs (1) in a package ab" KOBACO Z N ijbcj Total number of TV block ad units in daypart A among programs (j ) in a package abc KOBACO ZN TVaBbcj Total number of TV block ad units in daypart B among programs ( j ) in a package abc KOBACO BL . ZNTVC Total number Of TV block ad units in daypart C among programs (1 ) in a package abc KOBACO j abcj 38 Table l (cont’d) ZNR C Total number of religious broadcasters’ block ad units in daypart C among programs (j ) in a package abc PG ’ Z N 1!) , Total number of relrgrous broadcasters program ad units In daypart A among programs ( _] ) In a package abt KOBACO j c ('j PGB . . . Z NR I , Total number 01 religious broadcasters‘ program ad units in daypart B among programs ( j ) in a package (the KOBACO j a )(J PGC Z N I _ Total number of religious broadcasters’ program ad in daypart C among programs ( j) in a package abr- KOBACO J a )(J BLA . , _ . ZNR I _ Total number of relIgious broadcasters’ block ad umts 1n daypar= A among programs (j ) In a package (the KOBACO j a 7‘7 BL}, . . . . . 7 NR I , Total number Ofrel1gious broadcasters’ block ad umts 1n daypart B among programs (1 ) In a package abc KOBACO j a )1] BL KOBACO ; j abcj 39 thett toaH incre XX ,1 dhid pace. - I? -F;; However, this model could suffer from multicollinearity among variables because the total number of ad units in the package (2 N 5 ) is correlated, with a varying degree, 1' to all other variables in the model. That is, adding another unit into the package also increases audience size as well as ad units in one of dayparts. It is possible that Z N UT swamp everything else in the regression with this model. Hence, it is necessary to J divide the formula by z N UT to focus on per commercial unit price rather than package 1' price. This treatment produces a model where average price per unit in the package (PI- /Z N ”T ) is explained by average audience seconds per unit for each demographic characteristic In TV ([ZT AP VGI’”2049 / ZN; ], [2A7]; (32049 / Z N UT l, J PG A other / NIT AB 51/722049/ N-T A B/If2049/ NIT I; WV :1] 'IZT Z; 1 [2 TI 21 [Z Aféf’he’ /Z N VT ]) and the fraction of each daypart in TV and radio I V J PG PG PG T PG T ([gINTVI;9A /;NIJT- ], [ZNTVI (1 /ZNI.IT ] @NW; /;NV ], [§I_‘INTVIIC /;Nij ], [ZNTVLISA/ZN ], [ZNfVIA/ENVI, [ZNffié/ZNVT. ], [ZNTVC/ZN.-], PG PG BL [Zr/.4IZNILIMP/2mIZNR..CIZNIII2~.AIZNIL J V J J V J J U j J V J 40 BL BL [X NR..B /ZNyT-], [Z NR..C /2 N5] ). As the sum ofthe fraction terms equals to 1, J' ’1 J' J ’1 I however, one needs to remove a fraction term (say, fraction of TV program ads in daypart B) from the following model as a base case. T _ A A PC 2049 T A PG 2049 T RIZNV —a+fll(ZATVIf” /ZNy-)+fl2(ZATV_If /ZNI.J-) J J ’1 J J ’1 J " PG T A BL T + .642 Angst” IZNV )+/3.(Z ATVI’T’2049 IZNV- ) J J J J J J A BL A BL 2049 T -T “LANE/INA /ZNIJ) +fl6(ZATV?ther/ZNIJ) J ’1 J J ’1 J A PC A PG SA T ,4 T +al(;NTVII /;NV)+52(;NTVII lgNy) A PG A BL " BL C T SA T ,4 T +53(;NTVII /;NU)+64(;NTVIJ_ /;Nij)+65(;NTVIj lgNy) A BL A BL A m B T C’ T A T +a6(;NTVII /§NN+67(;NTVIJI /21:NI-j)+58(;NRIj /;Nij) A PG A PG A 3L B T C T A T +59(;NRII /ZJZNII.)+5IO(;NRIJI /;NV)+5“(;NRII /;Nij) " BL A BL B T C T +512(§IINRII /2jINy-)+613(ZJINRIJI /§j:NI-j)+eij (3.6) Once estimation is complete, implicit market prices for individual ad units can be computed by using regression coefficients. As per equations (3.2) and (3.3), coefficient estimates are the same for the individual spot prices and the package prices and they remain the same for the average package prices per unit in formula (3.6) where both sides of the package price equation are divided by the total number of ad units in the package. 41 The coefficients of average audience seconds per spot in formula (3.6) can be interpreted as the unit price increase attributable to a one unit increase of audience seconds in the particular ad slot. The coefficients for the fraction terms of dayparts can be interpreted as if they are coefficients for dummy variables for the respective dayparts in the pacakge. To explain the logic, let us assume one of the fraction terms turns out to be 1. This means the package is composed of a single product (say, TV program spots in daypart SA) and the average spot price of the package is merely the average spot price of that particular type of spot (i.e., TV program spots in daypart SA). The constant term in the model can be interpreted as the coefficient of the base case. Hence, the implicit market price for an individual ad unit can be estimated by applying the coefficients estimated with the package prices to the individual A A A characteristics of the purchased ad time: ,6] , ,62 , and ,63 respectively are multiplied times the male 20-49 audience seconds, female 20-49 audience seconds, and audience seconds of male and female aged other than 20-49 for the individual spot of TV program A A A ads. ,64 , ,B5 , and 166 are multiplied times the male 20-49 audience seconds, female 20- 49 audience seconds, and audience seconds of male and female aged other than 20-49 for the individual spot of TV block ads. As the coefficients for the fraction terms of dayparts can be interpreted as if they are coefficients for dummy variables for the respective A A A A A A dayparts in the package, as noted above, 6 , 2,63,64,65,66,67,68,69,510,611,612 , — A and 513 , respectively are multiplied to the dummy value for each daypart. To the dummy value for daypart B, which is the base case, constant term is multiplied. 42 Estimation of Price Distortion Price distortion is defined as the gap between estimated implicit market price and the KOBACO set price for the particular ad slot. Hence, it is calculated by subtracting the estimated implicit market price from KOBACO-set price. For presentational purposes, however, average differences between KOBACO set prices and estimated implicit market prices are compared for each category (TV program ads in daypart SA; TV program ads in daypart A; TV program ads in daypart B; TV program ads in daypart C; TV block ads in daypart SA; TV block ads in daypart A; TV block ads in daypart B; TV block ads in daypart C; radio program ads in daypart A; radio program ads in daypart B; radio program ads in daypart C; radio block ads in daypart A; radio block ads in daypart B; radio block ads in dayaprt C) and for each broadcaster (BBS-F M; F BBC-AM; CBS-AM; CBS-FM; PBC-FM; WBC-FM). A comparison is also made between expenditures on ad units in each daypart calculated with the implicit market prices and those calculated with the KOBACO set prices. Estimation of Subsidies There can be two types of subsidy flows in the market. First, the external subsidy flowing among broadcasters, and they we estimated by subtracting each broadcaster total expenditures with KOBACO set prices from the estimates of what expenditures for the same units would be, with the implicit market prices estimated for each broadcaster. The internal subsidies flowing from commercial programs to public interest programs within a major TV network should be estimated by comparing expenditures for each program type. However, the estimation of internal subsidies cannot be completed unless public 43 interest programs are clearly identified. No one has undertaken this exercise and I will follow precedent and ignore this type of subsidy in this study. However, the method employed here could be used to examine internal subsidies. 44 CHAPTER 4 METHODOLOGY Data To test the proposed model, actual transaction data for the 100 largest Korean broadcasting advertisers were obtained from KOBACO for the one-year period May 2003 to April 2004. The large number of small advertisers (yearly, more than 6,500 advertisers bought at least one ad spot in terrestrial broadcasting programs) makes the task of gathering and processing data for all of them infeasible. However, expenditures by the largest 100 advertisers account for 64.3% of all terrestrial broadcast advertising revenues and dominate in the determination of ad time prices. So it is unlikely that restricting the sample in this way is a source of significant bias in the estimates. Furthermore, I assume this introduces no bias to the estimates as I can’t think of reasons why advertisers smaller than the 100 largest should value the ad slots differently at the margin that do major advertisers. Plus, if there is competitive bidding among all advertisers for access to ad time slots, then the same competitive implicit market prices should apply to all of them. The sample period is concurrent with the upfront markets where contracts for ad slots with duration longer than six months, airing May 2003 to April 2004, were negotiated. From the data, advertisers and advertising agencies were identified by randomly allocated numeric codes preserving anonymity. Other information in the data included spot prices set by KOBACO, airing seconds of the ad slots, and contract duration of each 45 ad slot. The data also included the audience ratings of programs to which the purchased ad slots were attached. Audience ratings of TV programs were subdivided into those for males aged 20-49, females aged 20-49, and males and females of ages other than 20-49. In the sampling period, Nielsen Media Research (NMR) and Taylor Nelson Sofres (TNS) conducted audience research on 1550 and 1200 TV household panels respectively, employing people meter technique (Lee, 2004). NMR audience ratings were used for this study. However, the reporting format of SBS audience ratings differed from those of KBS and MBC audience ratings. While audience ratings for KBS and MBC programs were averaged nationally, those for SBS programs were reported separately for each region covered by networked local broadcasters. Hence, locally surveyed audience ratings of SBS programs were averaged by weights of audience size in each region, to calculate national average audience ratings for networked programs. The original data contained 102,080 contracts made with major TV networks (23,681 with KBS TV; 38,099 with MBC TV; 40,300 with SBS TV) and 16,246 contracts made with religious broadcasters (2,658 with BBS-F M; 4,214 with CBS-AM; 1,975 with CBS-FM; 1,680 with FEBC-AM; 2,925 with PBC-FM; 2,794 with WES-FM). The data did not include ad contracts for “yearly sports” programs that presented the major sporting events held through the year. Advertisers deposited certain amount of their ad budgets in advance for the ad time attached to those programs. Due to this transaction pattern, ads on the yearly sports programs were regarded as not packaged with other programs. In addition, data did not include local ad spots as they tend not to be packaged with ads broadcast nationwide. 46 However, the original data contained errors or missing values. A major source of errors is incorrect record-keeping of contract periods. The data included starting and ending dates for the supply of commercial time in a program, but in some instances, end dates were recorded prior to starting dates. I acquired the number of ad slots purchased by an advertiser for a particular program by counting the number of aired days for the ad slot within the contract period. Hence, errors in contract dates made it impossible to count the number ad slots during the contract periods. For example, if an ad slot in a program was filled by a commercial message every Monday for a three-week period, the particular advertiser was assumed to buy three ad slots for the program. Also, audience ratings were missing in some instances. Those observations with obvious errors or missing values were removed from the data. Afier excluding all problematic observations the data set included 98,558 contract cases, made with major TV networks (22,864 with KBS TV; 36,946 with MBC TV; 38,748 with SBS TV) and 10,585 contract cases with religious broadcasters (1,978 with BBS-FM; 3,162 with CBS-AM; 1,714 with CBS-FM; 1,264 with FEBC-AM; 1,432 with PBC-FM; 1,035 with WBS-FM). Measurements Package Price: Package price is operationalized as the amount an advertiser spent on ad time sold by a network (and its associated religious broadcasters), through a specific ad agency, during the sample period. As each of the KOBACO sub-units18 sold ad time for one of the three major TV networks and its associated religious radio broadcasters to ad agencies (see figure 1), it is reasonable to assume that packages were '8 Three KOBACO subunits exist: one to represent KBS-TV, KBS radio stations, EBS-TV, FEBC-AM, and Sunny FM; one to represent MBC-TV, MBC radio stations, CBS-FM, CBS-AM, PBC, and KP M; one to represent SBS-TV, SBS radio stations, BBS-F M, WBS-F M. 47 constructed per ad agency per advertiser for broadcasters represented by each of the KOBACO sub-units. In figure 1, the separate arrows represent individual packages. This implies that a package created for an advertiser by one agency was not combined with the package created for the same advertiser by the second agency. Also, this implies that a package was not created by combining ad slots across the major networks (and their associated religious broadcasters) represented by each of the KOBACO sub-units. While this method is a way of dealing with the absence of data identifying individual packages, it has the limitation of treating all purchases by an ad agency for an advertiser as a single package, when multiple packages may have been purchased. However, this does not violate the logic of the package-price regression approach outlined above, as KOBACO prices are the same for all packages. The downside of treating all purchases by an advertiser through a particular ad agency as the purchase of a single package is that it reduces the number of observations. Nevertheless, if there is enough variation among the constructed packages bought by different advertisers through different ad agencies, it becomes possible to estimate significant coefficients identifying impacts of audience demographics and other characteristics of component programs on the package prices which, in turn, makes it possible to estimate implicit market prices for individual programs. While it is desirable to use observed market prices according to economic theory, using a proxy variable for prices causes no problem from an estimation perspective. Package prices were calculated by adding all the KOBACO prices for ad spots purchased by an advertiser (a) through a particular ad agency (b) from a network (and 48 its associated religious and local radio stations) (c ). This definition can be presented via the following formula: Pabc : gijabcj (4.1) Where a is advertiser, b is advertising agency, c is network (henceforth, I will use “network” to include a network’s affiliated religious broadcasters), and j is a program on the network. k j is a KOBACO set price for an ad spot attached to program j and x a bcj is the number of ad spots associated with program j, purchased by advertiser a through advertising agency b from network c. While the data set contained prices set by KOBACO, the numbers of ad slots purchased at these prices were not provided. Hence I have assumed the number of ad spots aired during the contract period to be the same as the number of days a commercial was aired during the contract period in the network or the associated religious broadcasters whose time was purchased. Audience Size per Demographic Characteristic: Audience size of a package is operationalized in terms of total audience seconds of the component programs in a package. Individual audience seconds for TV program ads in a particular demographic PG PG PG (A ”’2049 for males 20-49, A f2049 for females 20-49, A 0m” for males and TV TV TV abcj abcj abcj females with ages other than 20-49) were calculated by multiplying the audience rating of PG PG PG , , the program (R j "’2049 , R j f2049 , R j 0m” ) times the total population of the corresponding demographic group (Pfi,2049 , FTC/2049 , PTof/her ), and the length of a commercial measured in seconds of each ad slot purchased by an advertiser for a 49 particular program (S is the number of ad slots attached to program j abcj )' xabcj purchased by advertiser a through advertising agency b from broadcaster c during the sample period. Hence, total audience seconds of program ads per demographic group in a acka e AP Gm2049 A PGf2049 AP 00"” is the sum of audience seconds p g (ZTV ZTV TVabcj ZTV TVabcj ) calculated for the component programs, as the following formula shows. :14]? m2049_ =Z(Rf Gm2049 x P75132049 XS Vabcj abcj X xabcj) 2049 2049 2049 ZATVf =Z(Rf Cf x1374) xS xx - ) a bq €1ij abcj G_.0ther _ Z( R Gather XPotherx S 4.2 Vabcj ( ) ZAPV However, as no published data are available for TV population specified by the abcj x xabcj ) demographic characteristics, the calculation was made with the assumption that 100% of the population in each demographic group watched TV. The Korea Statistical Yearbook 2004 provides the number of Koreans by gender and age. All the measures for males 20- 49, females 20-49, and the others are counted as the potential viewers in each demographic category. S a be j is the length in seconds of every ad spot purchased by an advertiser. xabcj is the number of ad slots attached to program j purchased by an advertiser through a particular advertising agency from a broadcaster during the sample period. Audience seconds for TV block ads were calculated following the same process used for TV program ads except the audience ratings of the program 50 BL BL BL . _ (R j ”’2049 , R j ”049 , R j 0m” ) were measured d1fferently. As block ads are located in the middle of two programs, it was hard to associate the block ads with the audience ratings of either program. Hence, audience ratings of two adjacent programs are averaged for the block ads. Daypart: TV dayparts are classified as SA, A, B, and C as described above. SA is equivalent to the primetime daypart in the USA broadcasting system, A to primetime fringe period, C to early morning and late night, and B to other times. For program ads, dayparts were first dummy-coded for daypart SA, A, B and C and then weighted by the PG PG B PGS A A PGC _ length of ad 3 ot (D , D , D , and D ). By settin a 15 second ad spot P TV j TV j TV j TV J. g as a base case for TV ads, weights were calculated by dividing total ad seconds for each spot by 15. Then, the weighted dummy values were multiplied by the number of ad slots .) and summed for each package bought by an advertiser through a in program j (xabcj particular ad agency. As the sum of weighted dummies are the same as the total number of ad units, as discussed above, notation for dummy “ D ” was replaced with the number of spots “ N ” here, as shown by the following formula: PG PG N SA = (D SA x x ) 2]: TV ; TV a bcj £2ij abcj PG PG N A = (D A xx .) ; TVabcj ; TVabcj abcy PG PG N B = (D 8 xx .) g: TVabcj ; TVabcj (7ij PC PC N C = D C X x . 4.3 51 This process was applied in the same way to TV block ads and radio ads for both program ads and block ads. Weights were calculated by dividing ad seconds of each spot by 20 for radio ads as radio ad time was generally sold in 20 second units. Construction of Packages: Using the pivot function in Microsoft Office Excel 2003, individual contracts are summed over the advertisers and ad agencies. It returned 467 package cases. This means that the 100 largest advertisers bought ad time through three different KOBACO sub-units and that some advertisers made deals through more than one ad agency. Among the 467 cases, 151 cases were made through the KOBACO subunit representing KBS-TV and its associated religious broadcasters, while 161 cases were made through the subunit representing MBC-TV and its associated broadcasters and 155 cases were made through the subunit representing SBS-TV and its associated broadcasters. 52 CHAPTERS RESULTS This chapter reports regression results obtained using package prices, defined as advertisers’ annual ad budgets spent in a particular network (and its associated broadcasters) through a particular advertising agency. By this definition, 467 package cases originally were constructed. However, due to missing values in the data, 12 cases were automatically dropped from the analysis and 455 cases were used for estimation where the average price per unit in the package (APPU) was KW 3,172,547 million, and each component of the advertising types comprises packages in proportions shown in Table 2. The columns values of minimum, maximum and mean for the fraction variables represent the proportions composing the package. On average, program advertising in daypart A with religious broadcasters comprised the largest proportion, 21% of the total spots in package, while program advertising in dayparts A and B with the major TV networks comprised 18% each. Program advertising in daypart SA and daypart C in the major networks comprised 14% and 9% each. Program advertising in daypart B in religious broadcasters comprised 7%. In sum, 86% of the total package spots comprised these six types of advertising and the remaining 14% were comprised of block advertising in the major TV networks and religious broadcasters plus program advertising in daypart C in the major TV networks. Average audience seconds per unit (AASPU) for TV program advertising were 14,709,000 while those for TV block advertising were 2,698,000. AASPU for both program and block advertising on radio were not taken into 53 Table 2. Descriptive Statistics _ Before Outlier Removed N Minimum Maximum Mean Std. Deviation Average Package Price Per Spot 455 18,627 10,005,000 3,172,547 1,501,459 Average F2049 Audience Seconds of TV Program Ads 455 0 21,416 4,787 2,395 Average M2049 Audience Seconds of TV Program Ads 455 0 10,341 3,090 1,538 Average Other’s Audience Seconds of TV Program Ads 455 0 26,205 6,826 3,480 Fraction ofTV Program Ads in Daypart SA 455 0 1.00 0.14 0.11 Fraction of TV Program Ads in Daypart A 455 0 0.83 0.18 0.12 Fraction ofTV Program Ads in Daypart B 455 0 0.83 0.18 0.14 Fraction of TV Program Ads in Daypart C 455 0 0.73 0.09 0.10 Average F2049 Audience Seconds ofTV Block Ads 455 0 15,310 880 1,287 Average M2049 Audience Seconds of TV Block Ads 455 0 13,147 559 941 Average Other Audience Seconds of TV Block Ads 455 0 25,802 1,259 1,878 Fraction of TV Block Ads in Daypart SA 455 0 0.91 0.04 0.07 Fraction of TV Block Ads in Daypart A 455 0 0.48 0.02 0.05 Fraction of TV Block Ads in Daypart B 455 0 0.60 0.03 0.05 Fraction of TV Block Ads in Daypart C 455 0 0.20 0.01 0.02 Fraction of Religious Radio’s Program Ads in Daypart A 455 0 1.00 0.21 0.20 Fraction of Religious Radio’s Program Ads in Daypart B 455 0 0.63 0.07 0.10 Fraction of Religious Radio’s Program Ads in Daypart C 455 0 0.14 0.01 0.02 Fraction of Religious Radio’s Block Ads in Daypart A 455 0 0.90 0.03 0.08 Fraction of Religious Radio’s Block Ads in Daypart B 455 0 0.16 0.01 0.02 Fraction of Religious Radio’s Block Ads in Daypart C 455 0 0.11 0.00 0.01 54 acco 01‘ dz 1101' 1356 to [1 101: regi \l‘t’r 06$ SUC CU account in this analysis due to lack of data. However, advertisers work with the same lack of data. Therefore, this treatment is believed not to cause a bias. Model Re-speeification Before the main analyses were conducted, data were screened for outliers. However, outlier presence is unrelated to sampling error or incorrect data entry by a researcher, as population data provided by KOBACO were used in the analysis. Referring to the Tabachnick and F idell’s (1996) definition of outlier, two strategies were employed to remove potential outlier impacts: remove cases more than 3 standard deviations from the mean in the dependent variable and another ten cases having highest residuals in the regressions from the visual inspection of the residuals plot. With this measure, 12 cases were removed from the data and 443 cases were left out of 455.19 A complete data description is presented in Table 3. After outliers were removed, Pearson correlations among the variables were checked, as Table 4 showed. It was found that, while correlations between other independent variables are .79 at the highest, correlations between the audience seconds of demographic groups were extremely high, .92 to .98. Three possible reasons exist for such high correlations. First, this could be the nature of the original data. Due to certain cultural reasons, Koreans may watch TV with little variation across demographic groups, hence, audience ratings reported by Nielsen Media Research may have originally high correlations. If this is the case, the logic of employing demographic composition as a variable affecting advertising prices does not apply to the Korean broadcast market and '9 I also ran a regression with outliers and found that exclusion of outliers did not change the qualitative nature of my findings. 55 Table 3. Descriptive Statistics N After Outlier Removed N Minimum Maximum Mean Standard Deviation Average Package Price Per Spot 443 18,627 7,275,000 3,078,250 1,378,650 Average F2049 Audience Seconds of TV Program Ads 443 0 1 1,437 4,655 2,095 Average M2049 Audience Seconds of TV Program Ads 443 0 8,276 3,017 1,423 Averag e Other’s Audience Seconds of TV Program Ads 443 0 18,104 6,671 3,204 Fraction of TV Program Ads in Daypart SA 443 0 0.58 0.13 0.10 Fraction ofTV Program Ads in Daypart A 443 0 0.83 0.17 0.12 Fraction of TV Program Ads in Daypart B 443 0 0.83 0.18 0.14 Fraction of TV Program Ads in Daypart C 443 0 0.73 0.09 0.10 Average F2049 Audience Seconds of TV Block Ads 443 0 9,534 841 1,086 Average M2049 Audience Seconds of TV Block Ads 443 0 7,266 529 733 Average Other Audience Seconds of TV Block Ads 443 0 12,1 15 1,193 1,464 Fraction of TV Block Ads in Daypart SA 443 0 0.65 0.04 0.05 Fraction of TV Block Ads in Daypart A 443 0 0.48 0.02 0.05 Fraction of TV Block Ads in Daypart B 443 0 0.60 0.03 0.06 Fraction of TV Block Ads in Daypart C 443 0 0.20 0.01 0.02 Fraction of Religious Radio’s Program Ads in Daypart A 443 0 1.00 0.21 0.19 Fraction of Religious Radio’s Program Ads in Daypart B 443 0 0.63 0.07 0.10 Fraction of Religious Radio’s Program Ads in Daypart C 443 0 0.14 0.01 0.02 Fraction of Religious Radio’s Block Ads in Daypart A 443 0 0.90 0.03 0.08 Fraction of Religious Radio’s Block Ads in Daypart B 443 0 0.16 0.01 0.02 Fraction of Religious Radio’s Block Ads in Daypart C 443 0 0.11 0.00 0.01 56 Table 4. Pearson Correlations of Package Data Ix) 5 6 7 8 9 10 ll 20 Average Package Price Per Spot 1. 2. Average F2049 Audience Seconds ofTV Program Ads 3. Average M2049 Audience Seconds ofTV Program Ads 0.96 4. Average Other’s Audience Seconds of TV Program Ads 0.92 0.95 5. Fraction of TV Program Ads in Daypai SA 0.80 0.69 0.70 0.70 6. Fraction of TV Program Ads in Daypart A 0.69 0.70 0.68 0.70 0.27 7. Fraction of TV Program Ads in M 0.17 0.12 0.20 0.05 0.00 0.04 8. Average F2049 Audience Seconds of TV Block Ads 0.07 —0.03 —0.01 —0.05 -0.03 —0.10 —0.01 9. Average M2049 Audience Seconds of TV Block Ads 0.09 -0.02 0.02 -0.04 0.00 —0.10 0.00 0.97 10. Average Other Audience Seconds of TV Block Ads 0.10 —0.01 0.02 —0.02 —0.01 —0.09 —0.01 0.98 0.96 11. Fraction of TV Block Ads in Daypart SA 0.13 —0.01 0.03 —0.01 0.08 —0.07 —0.03 0.77 0.79 0.78 12. Fraction of TV Block Ads in WA 0.01 —0.02 —0.02 —0.04 -0.04 —0.07 0.03 0.64 0.59 0.63 13. Fraction of TV Block Ads in Daypart B —0.08 -0.10 -0.11 —0.10 —0.16 —0.08 -0.02 0.55 0.45 0.53 0.33 14. Fraction of TV Block Ads in Daypart C —0.16 —0.16 —0.17 —0.19 -0.16 —0.15 0.01 0.27 0.21 0.25 0.24 0.54 15. Fraction of Religious Radio’s wAds in Daypart A -0.62 —0.60 —0.58 -0.61 —0.35 —0.47 —0.31 —0.28 —0.26 -0.29 -0.20 —0.22 -0.23 —0.09 16. Fraction of Religious Radio’s Program Ads in Daypart B —0.39 —0.38 —0.36 —0.36 —0.25 -0.23 -0.19 —0.21 -0.19 -0.22 —0.16 -0.15 -0.14 -0.05 0.15 17. Fraction of Religious Radio’s Program Ads in Daypart C -0.18 —0.18 —0.17 —0.16 —0.05 —0.15 -0.10 -0.09 —0.08 —0.09 —0.04 —0.06 —0. 10 —0.06 0.12 0.19 18. Fraction of Religious Radio’s Block Ads in Daypart A -0.29 —0.28 -0.28 -0.29 -0.20 —0.20 —0.13 —0.07 —0.07 —0.09 —0.09 —0.05 —0.04 0.00 0.01 —0.05 —0.04 19. Fraction of Religious Radio’s Block Ads in Daypart B —0.20 —0.18 -0.17 -0.20 -0.15 —0.14 -0.08 —0.05 —0.04 —0.06 —0.06 —0.04 —0.05 0.01 0.00 —0.05 —0.01 0.49 20. Fraction of Religious Radio’s Block Ads in Daypart C —0.11 —0.10 —0.10 -0.10 -0.08 —0.06 —0.07 —0.04 —0.04 -0.05 —0.04 ~0.02 —0.05 —0.02 -0.07 -0.06 —0.04 0.44 0.57 57 [ECO gror they the three different audience-demographics should be combined into one for the purpose of regression estimation. Otherwise, they will generate a multicollinearity problem in estimation. Second, this might be attributed to the measurement process of summing multiple spots into one package. In this case, how to measure audience size should be reconsidered. Third, it may just reflect possibility that the relative sizes of demographic groups in audiences don’t change nearly as much as their absolute sizes, even though they do vary. Table 5 shows that high correlation between demographic groups is not due to the measurement process. Correlations between individual programs’ audience ratings for each demographic group were high (for program ads, .93, .91, .91 in KBS; .96, .97, .95 in MBC; .98, .92, .90 in SBS between female 20-49 and male 20-49, female20-49 and other, male 20-49 and other respectively; for block ads, .95, .93, .93 in KBS; .89, .94, .87 in MBC; .90, .94, .91 in SBS respectively). This implies that audience segmentation in Korea does not have such critical weight as it does in USA. Reflecting on these findings, the regression model proposed in chapter 3 was re-specified as presented in equation (5.1). R 2 remained almost the same when audience demographic groups were combined into one (.96 in the model having three specified demographic groups; .95 for the model with them combined). T A A PG T A BL T 1)./2N.j =a+131