Khanp I o346u§< Iniiz‘...1§ 1‘. b.‘ ‘nla‘aW! I 39a ‘15: «KER 3 . l n . k «r , . . 4:5,?2 sham. :5“. .I. fin . i...» .. afl‘flfi i... . a 4 N1. .1! 4...... o» A. a. .3. ; . .Ywfinfii : I .. . 3..- . 2.3. L9. a... . . . .. a s... 3?. 1.. 24...... .1: Jammie .. ”is” .3.“ ..w.n..u...q. 13%. «T... .....utu‘:,..: 34.33.. .awufiavrmn. :i .1 _ 0' I. ’1' l o I In. . Ill 4i§<¥~Ot .60....»3! . .76.:ng LIBRARY Michigan State University This is to certify that the dissertation entitled Essays in Quantitative Macroeconomics presented by Facundo Sepulveda has been accepted towards fulfillment . of the requirements for Ph . D . degree in Economics Date August 21, 2002 MS U is an Affirmative Action/Equal Opportunity Institution 0-12771 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 OCT 0 2 2004 W * NOV 2 7 2005 .— 47.3—43.5 6/01 c:/ClRC/DateDua.p65-p.15 ESSAYS IN QUANTITATIVE MACROECONOMICS By Facundo Sepulveda A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Economics 2002 ABSTRACT ESSAYS IN QUANTITATIVE MACROECONOMICS By Facundo Sepulveda This dissertation contains three essays in quantitative macroeconomics. The first chapter, “Precautionary savings in general equilibrium”, uses a calibrated stochastic OLG model to address three questions about US savings and wealth accu- mulation: first, does an equilibrium display buffer stock savings by agents? Second, is this equilibrium consistent with savings behavior of US households? And finally, what level of precautionary savings arises when general equilibrium effects are accounted for? I find that given observed earnings risk, the rates of time preference that are consistent with the equilibrium are very close to the interest rate, so no buffer stock behavior is observed. Moreover, the equilibrium reproduces important facts about savings behavior of US households. Finally, accounting for general equilibrium effects lowers the size of precautionary wealth to about 35% of aggregate wealth, or 30 to 50% less than partial equilibrium estimates. The second chapter, “Green taxes and double dividends in a dynamic economy”, asks whether a tax recycling experiment would deliver a double dividend in the US economy. According to the double dividend hypothesis, environmental taxes may raise revenue that can be used to lower other (pre—existing) tax distortions apart from decreasing pollution externalities. This hypothesis is evaluated using a dynamic general equilibrium model of capital accumulation. i find that, although in the long run pollution may worsen, the green dividend -higher discounted utility from a cleaner environment- would be obtained under all tax changes, due to a better environment during most of the transition. The efficiency dividend however -higher discounted utility from consumption of traded goods— will obtain only for target levels of the green tax below a critical number. In the third chapter, “Training and business cycles”, I examine the behavior of skill acquisition through training at business cycles frequencies. First, a time series of training is constructed using individual data from the N LSY79 database. After documenting the cyclical properties of the series, I discuss what features are needed for a RBC model to successfully reproduce them. I find that training is weakly countercyclical, leads the cycle, and has a standard deviation of about ten times output. A model where employment, but not weekly hours, is costly to adjust, is able to account for most of the documented regularities. To Carolina, my wife, and Sebastian, my brother. ACKNOWLEDGEMENTS I would like to thank first of all my advisors Rowena Pecchenino and Gerhard Glomm, both for the time they gave me and for their encouragement. Rowena and Gerhard taught me how to think about economics and kept alive the academic ambition I brought to MSU. I am also in debt with my other committee members, Andrei Shevchenko, Ana Maria Herrera, and Jeff Biddle, for taking the time to read my dissertation and sharing their suggestions with me. Carl Davidson taught one of the most challenging courses I took at MSU, and Jeff Wooldridge made econometrics seem easy. I learnt much from them. In Argentina, Professor Julio Olivera made me aware for the first time of a sense of possibility in academic work, and Jorge Katz and Miguel Teubal encouraged and helped me pursue graduate studies. A number of friends were responsible for making my life in the States a rich and worthwhile experience: Bulent, Claudia and Nestor from Rochester: Onur, Rodrigo and Maite, Noemi, Jenny and Noel, Luz Maria, Eduardo Paulino, Linda Bailey and Zhehui, Alonso, Luis and Maria Alejandra, at MSU. Two of these friends, Fabio and Daiji, also shared with me their intellectual enthusiasm, and I owe them in two currencies. Finally, thanks to my family: Carolina, my parents Sergio and Ana, my grandmother Irene, Javiera, and Sebastian, my brother. They, with their unconditional love and support are the main reason why I have completed this work. Contents 1 Precautionary saving in general equilibrium 1.1 Introduction .................................. 1.2 The model ................................... 1.3 Calibration. .................................. 1.4 Results ..................................... 1.5 Conclusions .................................. 2 Green taxes and double dividends in a dynamic economy 2.1 Introduction .................................. 2.2 The model ................................... 2.3 Calibration .................................. 2.4 Results ..................................... 2.5 Conclusion ................................... 3 Training and business cycles 3.1 Introduction .................................. 3.2 Data ...................................... 3.2.1 Data description ........................... 3.2.2 Stylized facts ............................. 3.3 Model ..................................... 3.4 Calibration .................................. 3.5 Results ..................................... vi 13 23 23 28 3O 32 40 40 42 42 47 3.6 Conclusion ................................... A Numerical methods. A.1 Solution method for the stochastic OLG model ............... A.2 Solution method for the deterministic OLG model ............. B Standard RBC model with human capital C First order conditions in the household problem [P2] vii 70 70 71 73 75 List of Tables 1.1 1.2 1.3 1.4 1.6 1.7 2.1 2.2 2.3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Calibration .................................. 14 Carroll-Samwick estimates for sensitivity of wealth holdings with respect to income risk ................................ 15 General equilibrium estimates of precautionary wealth .......... 16 Partial and general equilibrium estimates of precautionary wealth (‘70) . 17 Reproducing results: ”/0 of wealth that is precautionary .......... 18 Partial vs. general equilibrium effects ................... 19 Selected capital output ratios ........................ 20 Benchmark parameters and data ...................... 34 Euler residuals (er) .............................. 34 Welfare analysis: Compensating variation ("/c) ............... 35 Assignment of training program ....................... 63 Descriptive statistics ............................. 63 Description of variables ........................... 64 Contemporaneous correlation of 1, hours and productivity with GDP- Contemporaneous correlations of training with GDP, I-Data ....... 65 Cross correlations of I, H and productivity with GDP-Data (correct, gdl)!+ 1)) 66 Cross correlations of training with GDP-Data ((‘0-r'r(;1:t, 51(1thr 1)) ..... 67 Standard deviations-Data .......................... 68 viii 3.9 Baseline parameter values .......................... 68 3.10 Cross correlations with output-Model ((#01‘1‘(:Et,gdpt+j)) .......... 69 3.11 Standard deviations—l\"l(;)(_lel .......................... 69 3.12 Sensitivity analysis .............................. 69 B.1 Variable description .............................. 74 ix List of Figures 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.1 2.2 2.3 2.4 3.1 3.2 3.3 3.4 3.5 Income profile (Hubbard et a1. [1994], 12-15 years of education) ..... 14 Age-wealth profile: Baseline model ..................... 15 Age-wealth profile: Models 2 to 4 ...................... 16 Age-wealth profile: Models 5 to 7 ...................... 17 Average propensities to save ......................... 18 Wealth/ income profile: Baseline model ................... 19 Wealth/ income profile: Model 2 ....................... 20 Wealth/ income profile: Model 6 ....................... 21 Age-wealth profile: Stochastic and deterministic economies ........ 22 Steady state comparisons: fuel ........................ 35 Steady state comparisons: capital ...................... 36 Transition path: capital ........................... 37 Transition path: fuel ............................. 38 Transition path: GDP and final goods consumption ............ 39 Impulse responses: Time allocations. .................... 58 Impulse responses: GDP, C, I ......................... 59 Training and GDP, period 1. ........................ 60 Tiaining and GDP, period 2 .......................... 61 {6, €HC’,train-ing} pairs consistent with the steady state ........... 62 Chapter 1 Precautionary saving in general equilibrium 1. 1 Introduction It is now understood that precautionary motives for accumulating wealth play a key role in the consumption/savings decisions of households. At least since the work of Skinner [1988], Hubbard and Judd [1987], and Summers and Carroll [1987], precaution- ary savings behavior has been extensively studied. primarily as a candidate solution to problems in the consumption literature, such as the excess sensitivity puzzle (Zeldes [1989], Caballero [1991]), and the failure of standard finite horizon models to explain the observed pattern of consumption growth over the life cycle (Skinner [1988]). Alter- natively, precautionary motives have been advanced to link the decline in the personal savings rate over the last 20 years to the extension of social insurance programs such as Medicare and Social Security (Summers and Carroll [1987]). This paper is concerned with a research agenda fostered by Skinner [1988], Carroll and Samwick [1998, 1997], Hubbard et al. [1994] (HSZ), Huggett [1996] and others. The objective is to study whether a model with realistic lifespans, income paths, and risk exposure can account for the savings/consumption behavior of US households. In this line of work, Hubbard et al. [1994] showed that in a calibrated model where the interest rate is close to the rate of time preference, agents would desire to accumulate levels of wealth similar to those found in the data. Moreover, evidence was reported that other model statistics such as the age-consumption profile, and the response of consumption to innovations in income could also reproduce their data counterparts. In a companion paper (Hubbard et al. [1995]) these authors focus on the importance of asset tested programs to explain the low accumulation of assets by the lowest. quintile of the wealth distribution. The calibration of these models was criticized by Carroll and Samwick (Carroll and Samwick [1998, 1997]), on the grounds that it produces a level of sensitivity to changes in income risk so high that it was impossible to reconcile with their empirical findings. Instead, they propose a calibration where agents have very high levels of impatience, so that the rate of time preference is well above of the interest rate. In such model, agents find it optimal to achieve a target level of wealth over (expected) income, which they keep until late in their life cycle. Carroll and Samwick report that this model displays a sensitivity to changes in income risk more in line with their empirical results. One common finding of this literature is that wealth that is held for precautionary motives accounts for at least 50% of total wealth. However, these estimates are partial equilibrium in nature, as prices do not respond to changes in aggregate wealth 1. As shown by Hubbard and Judd [1987] in a model with longevity risk only, and by Aiyagari [1994] in the context of an infinite horizon model, general equilibrium effects can be sizable and tend to increase wealth holding, therefore reducing the estimated share of wealth that is precautionary. This paper contributes to the literature by taking an alternative path: imposing the discipline of general equilibrium, we compute the levels of discount rates consistent with observed levels of interest rates, savings rates, and income/ longevity risk. We show that the resulting equilibrium produces interest and discount rates that are very close to each other, so that agents are not buffer stock savers. Moreover, the age specific saving behavior that emerges is consistent with average asset accumulation by US households, 1An exception is Huggett [1996] who carries a general equilibrium analysis and reports a lower estimate. However, his focus is on wealth distribution, so there is no discussion of this result. and displays levels of sensitivity to income risk in line with those reported by Carroll and Samwick. Finally, we compute the level of precautionary savings that arise in this model, and show that properly accounting for general equilibrium effects considerably lowers previous estimates. This chapter has four other sections. In section 1.2 the model is presented. Section 1.3 discusses the calibration procedure. Section 1.4 presents the results, and Section 1.5 concludes. 1.2 The model We present a large scale OLG model in the tradition of lmrohoroglu et al. [1995], Huggett [1996] and Rios-Rull [1996]. In this model, a large number of agents of size 1 live for a maximum of T periods, are endowed with a level of assets (1.1 at the beginning of their life (t = 1) and face uncertainty regarding labor earnings and lifespan. Each period, agents take the interest rate and the realization for labor income as given and must allocate their earnings between consumption and saving, subject to a borrowing constraint. Agents take prices as given and maximize a utility function of the form: T t max E 7 x 3’11. C cunt“ lt:1[J-:l—Il [J]; ( t) 81.. at“ + C, 2 (1+ r)a.t + nit/alt + q art-+1 Z 0, where it, is a random variable with bounded support that represents a shock to labor endowment, and (15, is a nonstochastic variable that indexes labor productivity for an agent of age t. Therefore, 112495,, is the unconditional mean of labor earnings at age t, that can be thought of as the life cycle component of earnings, and it, is labor endowment of an agent at age t. An agent of age t survives to t + 1 with probability 7),, With probability 1 — 17,, he dies and leaves bequests that are evenly distributed among all living agents, each agent receives q in bequests every period. Survival probabilities {1),},7‘21, in turn define the cohort shares {ad}; by n, = (1 — mm,“ and 2;, at = 1. The household problem can be expressed in recursive form. Let V,(a,l) be the maximum value of the objective function for an agent of age t with a level of asset holdings and labor endowment shock {a, l} . Then, Vt(a, l) is given by: We. 1) = m,ax{u(c> + max/...(a', n01} (1.,c s.t. a' + c = (l + 'r)a + 1096,14» q (L’ 2 0 (P1), where a’ is asset holdings for next period. Moreover, since an agent lives at most for T periods, we have: VT((I'9Z) = I115}X{U((-')} s.t. c 2 (1+ T)(L + 10qu + q The solution to this problem are the optimal policy functions Ct(a, l) and A¢(a,l), for t = 1, ...,T, that map the state {(1, l} at age t to consumption at age t and assets at the beginning of age t + 1 respectively. The representative firm chooses {L, K} to solve: nlralx F(K, L) — RK — wL (P2). To complete the description of the economy, we define the capital accumulation tech- nology in a standard way: K (+1 2 (1 — (5)11} + 1,, where I is aggregate investment and 6 is the depreciation rate. We are interested in a steady state equilibrium where the aggregate capital stock is constant, and although there is a large amount of dynamics at the individual level, 4 the distribution of assets and other endogenous variables is time invariant. Since a meaningful equilibrium concept needs to be expressed in terms of these distributions, we proceed to define them. Let (X, B, ‘15) be a probability space. If Z is the support for the stochastic shock it and asset holdings are restricted to lie in [0, 00), then an individual state :1: = {(L, l} lies in the state space X = Z x [0.00). Let B be the Borel sets in X. Then, for each t from 1 to T a distribution \Ilt can be defined such that, for each B E B,\II,(B) is the probability that an agent of age t will be in a state :1: E B . Together with the stochastic process for l, the optimal policy function A,(a, 1) defines a transition function P(B, t) = P'rob(:r,+1 E B |:1:,) that links current and future distributions. The function ‘11, is then derived recursively by: \II,(B) 2/ P(B,t — 1)(1\II,_1 B e B. X Equilibrium Definition: A steady state equilibrium for this economy is a collection of value functions Vt(.), policy functions C,(.) and At(.), t = 1,...,T; prices for labor and capital services {21),7‘}; aggregate values for {K, L}; a level of per capita bequests q; and distributions {\Ilt, 13,} for t = 1, ,T such that, 1. Households maximize utility: given q and prices {u}, r}, the policy functions C¢(.) and At(.) solve (PI) for all t. 2. Firms maximize profits: Fl" : R = 7‘ + 6 FL = w. 3. Markets clear: (0 Zr I": “C: + AIW‘I’t + (I = (1 — (5)1" + F(K, L) (ii) Zilltébt = L = 1 (Ill) 2! [it i Atdqlt = A, 4. Cross section distributions are consistent with policy functions: ‘I’tH = fptd‘l’t 5. All bequests are distributed: ‘1 = 21(1 - "1!)fAtd‘I’i Aiyagari [1994] presents a characterization of this problem in the context of an infinite horizon model: agents will overaccumulate assets, with respect to a complete markets situation, as a way to partially insure themselves against. the possibility of being effectively borrowing constrained in the future. The pattern of wealth accumulation is studied by Carroll [1999] in a life cycle model, and Deaton [1991] in an infinite horizon economy. An important result is that, when the growth rate of income is sufficiently high for given levels of risk {/1473}, prudence {0—3;}, and patience {13}, agents 01:)tirnally choose to achieve a target level of wealth over earnings, or “buffer stock” of assets 2. Checking whether this condition is empirically plausible is difficult given the unob- servable nature of the discount rate '7 = 1&2 The next section presents a calibration procedure where [3 is determined using the general equilibrium nature of the model. 1.3 Calibration. The calibration exercise is designed so that the stochastic: model economy displays rel— evant features of the US economy. In particular, the discount factor [3 is left as a free parameter that takes on the value needed for the model economy to display target levels of the interest rate and the savings rate. 2The condition in discrete time can be approximated by: r_——_'I + 0+1)0’2 < 0 2 9* where g is the growth rate of income, ’7' is the rate of time preference, and 0 is the coefficient of relative risk aversion. To calibrate the model we need to define functional forms and parameters. The functional forms used are as follows: 0 A Cobb-Douglas production function is used for all exercises: F(K, L) = AKOLI‘“ o Felicity functions are of the CRRA form: 0 The stochastic process for the labor endowment is AR(1): ln(l,) = pln(lt_1) + 6, 6, ~ N(0,03), Md. The parameter values are shown in table 1.1. For the earnings process we adopt the results for households with 12-15 years of education reported by Hubbard et al. [1994] (ta- ble A.4) using PSID data. Figure 1.1 shows the unconditional means. The stochastic process associated implies values of .946 for p , and .025 for of. These values are roughly consistent with findings by MaCurdy [1982], as explained below, but imply a variance in the change of earnings lower than the values in Abowd and Card [1989], who use the same dataset. The baseline economy is also calibrated so as to display the following ratios: an interest rate of 4% per annum, in line with the calculations reported by Kotlikoff and Summers [1981], and a savings rate of 19%, chosen to match the rate of investment over GDP of the US economy in the period 1980-1989. These ratios imply a depreciation rate of .045 per year. A comment of the calibration choices is in order. Evidence from longitudinal studies of earnings and labor supply suggest that the process for (log) earnings can best be modelled as a near unit root process with autoregressive errors of order 2 (MaCurdy [1982]. This leads Carroll and Samwick [1997] to calibrate their model using a unit root process with a variance of innovations equal to 0.01. As suggested by Skinner [1988], we can summarize the risk to lifetime resources implied by a AR(l) stochastic process with the following statistic: T—t - dam—10’ 2 1.; (1+ 7‘)J] 7i: = 0.2 I where c5, indexes labor earnings at each age. We compute this statistic (the average over all ages) for our baseline parameters, and compare it with those for Carroll and Samwick and MaCurdy, properly accounting for the ARM A specification. We find that the AR(l) process chosen here implies a similar level of risk to lifetime resources (2.54) than the ARM A(1, 2) proposed by MaCurdy (2.81) and the specification used by Carroll and Samwick (3.13). Moreover, increasing the variance of innovations from our baseline of .025 to .031 would be enough to produce a value of 3.13 for this statistic. With respect to the interest and savings rates, since the empirical equivalent of the model interest rate is a risk-free rate, we are tempted to use a number in the order of 1 / 2% per annum, consistent with the return on Treasury Bonds. On the other hand this rate is also the marginal product of capital, so the historical return on stocks, of the order of 7% annually but more volatile, may also be appropriate. We therefore experiment with different values of r. The problem of interpreting the savings rate lies in the fact that households are not the only source of savings in the US economy. In fact, from 1980 to 1989 the personal savings rate averaged 6.7% of GDP3, businesses contributed with 12.6 percentage points to the average savings rate, and the government dissaved .8% of GDP. Of these aggre- gates, businesses and government reported as capital consumption allowances 10.2 and 2.3% of GDP respectively. Aggregate gross saving was then in average 18.8% of GDP in this period, close to our benchmark, but the net saving rate was only 5.9% (ERP 3This is the contribution of rivate savin to a re ate savin and is different from the Personal , 7 Saving Rate in the National Income and Product Accounts, which is calculated as saving as a percentage of disposable (after tax) income, and does not take into account changes in asset. prices 8 [1999]). A related issue is that, since we focus on a steady state equilibrium, savings net of capital consumption (depreciation) allowances is zero in the model. Since introducing growth considerations is beyond the scope of this paper, we check the robustness of our results to the choice of savings rate by doing some sensitivity analysis with values of S/Y from 15% to 24%. Finally, note that Table1.1 show the levels of K/ Y implied by each choice of {7“, S/ Y } These levels are roughly consistent with the ratios of Assets/ Income reported by Hub- bard et al. [1994], but are in general higher than the capital-output ratios calculated for the US economy. Note that once the interest rate and savings rates are fixed, the depre- ciation rate and the capital output ratio are defined by the conditions .9 = 6K/ Y and r = F K — 6. Table 1.7, with the capital output ratios that result from selected {7“, S/ Y} pairs, show that a lower K / Y is associated with higher levels of saving rates and in- terest rates. While decreasing K / Y to 3 increases the estimated share of wealth that is precautionary (see table 1.3), it remains that this variation is small compared to the differences in precautionary wealth associated with different risk aversion coefficients. 1 .4 Results In this section, we begin by showing how the calibrated model reproduces important facts about wealth accumulation by US households. We then examine the implications of these results for the debate on whether US households are buffer stock savers or not. Finally, we compute the levels of precautionary wealth that emerge in this model and decompose it in partial and general equilibrium effects. We evaluate the ability of the model to mimic US data along three dimensions: the age/ wealth profile, the age-specific average propensities to save, and the sensitivity of wealth holdings with respect to income risk. The paper focuses on age-specific aggregate statistics, rather than distributions, because we believe that most of the intra cohort heterogeneity cannot be explained by different histories of shocks that are mean-reverting. It is known that this model compresses the income distribution, generating too few very rich (see e. g. Carroll [2000]) and too few very poor agents. Realistic models of wealth distribution imply types of heterogeneity in agents that are absent here: in investment opportunities (for instance Quadrini [2000]), in time discounting (e.g. Krusell and Smith [1998]). or in productivity (e.g. Hubbard et al. [1994]. Considering these types of heterogeneity is beyond the scope of this work. Figure 1.2 shows the predicted average profile of wealth holdings at each age (in thousands of 1984 dollars), compared to data reported by Radner [1989] using the 1984 Survey of Income and Program Participation (SIPP) database. The model generated data is normalized so that average income equals 1984 per capita GDP at current prices. The fit is extremely good given that the model was calibrated to savings and interest rates of the period only. The feature that deserves attention is the similarity of the shapes of the two curves, more than the fact that they overlap. In fact, since SIPP data comprises only private wealth, while the model’s data is on aggregate wealth, and their measurement units (households in SIPP versus ‘workers’ in model) differ, there is little reason why they should overlap. The similarities however suggest that, on average, the model contains the right elements that shape life cycle savings behavior. Figures1.3 and 1.4 present the age-wealth profiles for alternative parameterizations of the model, compared to Radner’s data. Clearly, very high levels of aggregate wealth can be attained by this model with the appropriate discount rate. We now turn to examine two direct measures of age-specific saving behavior. F ig- ure 1.5 compares the life cycle profiles of average propensities to save (APS) generated by the model with their data counterparts, constructed by Gokhale et al. [1996] using the Consumer Expenditure Survey (CEX) for various years. The two series correspond to different definitions of disposable income. Conventional disposable income is the 10 sum of labor income, capital income, and pension income minus net taxes, while in the alternative definition social security contributions are classified as loans (so that they are considered savings), and social security benefits are classified as the repayment of principal (not part of disposable income) plus interest on past social security loans. It is important to note that, once again, it is the shape of the APS curve and not the level that matters the most. Data. on household savings is data. on net savings, since businesses make most of the allowances for consumption of capital. In a growing economy this measure of savings should be positive in the aggregate. In our model, since we are focusing on a Steady State equilibrium, net savings are zero. The model prediction follows more closely the APS observed under the alternative definition, but it tends to overpredict savings rates at the beginning (until around age 32) of the life cycle. Overall, it displays the characteristic hump shape present in the data, with a ‘plateau’ from ages 35 to 60, and a drastic decrease after age 60. Figure 1.6 allows an examination of the sensitivity of wealth holdings with respect to uncertainty, measured in this case by the conditional variance of earnings of . The wealth / income profile for the baseline model is shown along with the average age-wealth profile of an agent facing the same prices as in the baseline model but with half of the variance (1.2% versus 2.4%). The results for two alternative parameterizations are shown in figures 1.7 and 1.8. These simulated changes in the levels of wealth holdings are consistent with those predicted by the regression coefficients in Carroll and Samwick [1997]. Using differ- ences in occupation specific income risk, Carroll and Samwick regress various measures of log net worth on the variance of permanent and transitory income shocks, perma- nent income, and life-cycle variables (age, married, etc). Using the approximation [log(Wl)log(W2)]/[vm'1 — var2] suggested by the authors, where W1,W2, and vnrrl, 11012 are wealth holdings and income variances for the baseline and alternative paths respectively, we can approxin‘iate what the regression coefficients would be in the mod- 11 els. The results, presented in Table 1.2, indicate that reasonable parameterizations of the model can reproduce these coefficients without difficulty. These levels of risk sensitivity are similar to those reported by Carroll and Samwick [1997], even though the levels of discount rates and other parameters are very close to those of Hubbard et al. [1994]. In fact, figures 1.6, 1.7, and 1.8 show that the ratio of wealth/ income chosen by agents, increases from the beginning of the life cycle, instead of remaining constant for the first part of it -after a target level is reached- as would be the case in a buffer stock model. Using the discount factors consistent with Steady State equilibria in the stochastic economies, we can predict how large would aggregate wealth be in a similar economy with no income uncertainty, and no income or lifespan uncertainty. We do so by using a certainty version of the program, described in the appendix. The results are shown in Table 1.3. It is worth noting that the levels of precautionary wealth are significantly lower than those found in similar models. Table 1.4 shows that the difference can be entirely explained by not accounting for general equilibrium effects. In what follows, we examine this issue more closely. Two exercises are carried out. First, we calibrate our model to interest rates, discount rates, and stochastic paths similar to those in Skinner [1988] and Hubbard et al. [1994]. Rather than attempting a detailed replication, we want to find if given these rough similarities, our model generates similar levels of precautionary wealth. Table 1.5 shows the results for two different levels of aggregate earnings, and confirms that in partial equilibrium this type of model generates high levels of precautionary wealth. Next, we compare the levels of precautionary wealth generated by these models in general vs. partial equilibrium (Table 1.6). Given the parameters for the stochastic process and the interest rate chosen in the original papers, we find the discount factor consistent with a predetermined savings rate (S / Y=.19 for Skinner and .24 for Hubbard et al.). Next, we find the level of aggregate wealth in a deterministic economy where 12 agents face the same factor prices (columns labelled PE), and finally we allow prices to change and compute the general equilibrium effects (columns labelled G.E.). It is clear that the partial vs. general equilibrium nature of the exercise matters, as was already noted in Hubbard and Judd [1987] and Aiyagari [1994]. In our examples, a partial equilibrium estimation of the size of precautionary wealth overstates it by 20 to 50%, consistent with the differences between the findings in this paper and those reported by Skinner [1988] and Hubbard et al. [1994]. 1 .5 Conclusions An important problem in the study of life cycle savings behavior is whether it can be characterized by a model of buffer stock versus ‘life cycle’ savings. This paper examines the issue using the discipline of general equilibrium to sort among alternative models. We find that a model calibrated to the levels of aggregate savings, interest rates, and risk exposure found in the data displays life cycle patterns of asset accumulation and overall sensitivity to risk in line with empirical evidence. This model does not predict buffer stock behavior. Rather, agents find it optimal to increase their wealth/ income ratios until shortly before retirement. At the same time, the equilibrium allocation implied a level of precautionary wealth around 35% of total wealth, far below comparable estimates in the literature. The dif— ferences can clearly be traced to the partial/ general equilibrium nature of the exercises. 13 Figure 1.1: Income profile (Hubbard et al. [1994], 12-15 years of education) Table 1.1: Calibration Income Profile 1.6 . , j , ,1 1.4 f: / -4 1.2 i- .- 1 - ‘ 0.8 L . 0.6 i- \ . 0.4 ' . L . - 4 A 20 30 40 50 60 7O 80 90 age '- [ Model ] Calibration Choices Implied Parameters [Stochastic Process ] S/ Y Interest R. 6 i3 6 K/ Y p 03 Baseline 0.19 0.04 3 0.9815 0.0447 4.25 0.946 2.5% Model 2 0.15 0.04 3 0.9983 0.0286 5.25 0.946 2.5% Model 3 0.24 0.04 3 0.9556 0.08 3 0.946 2.5% Model 4 0.19 0.03 3 1.011 0.0335 5.67 0.946 2.5% Model 5 0.19 0.05 3 0.959 0.0559 3.4 0.946 2.5% Model 6 0.19 0.04 5 0.9729 0.0447 4.25 0.946 2.5% Model 7 0.19 0.04 1 0.9763 0.0447 4.25 0.946 2.5% 14 Figure 1.2: Age-wealth profile: Baseline model Age—Wealth Profile:Baseiine Model 140 V I 1' r v 1 ‘1 r 120 ~ , A a 100 " fl *3 Model i " 30 r / *SIPP84 - Assets \ f 40.. . \ J 20. ,2. . / at/ 20 I so 40 so so 70 90 Age Table 1.2: Carroll-Samwick estimates for sensitivity of wealth holdings with respect to income risk Model Age<50 Age 1-82 C-S:Per. Var. 12.09 13.27 C-SzTr. Var. 7.11 6.6 Baseline 23.76 18.69 Model 2 21.76 14.88 Model 6 8.61 3.99 15 Assets Figure 1.3: Age-wealth profile: Models 2 to 4 180 Age-Wealfli Profile: Models 2 €04 160 I .4 M O O! O N O l l L Table 1.3: General equilibrium estimates of precautionary wealth Model Calibration Precautionary wealth (%) S/Y Interest R. 0 Lifespan All Uncertain Certain Baseline 0.19 0.04 3 27.33 30.09 Model 2 0.15 0.04 3 23.42 26.75 Model 3 0.24 0.04 3 31.94 34.08 Model 4 0.19 0.03 3 22.38 25.63 Model 5 0.19 0.05 3 29.63 32.07 Model 6 0.19 0.04 5 49.63 50.71 Model 7 0.19 0.04 1 6.69 11.81 16 90 Figure 1.4: Age-wealth profile: Models 5 to 7 Age-Wealm Profile: Models 5 to? Assets 140 1 j I I ' ‘I’ 7 I 120 3" be], - 3* A 4a,. +M0dol7 : 100 ”'32; ~Mod~el6 4 4; ~Moda|5 . \— I. so ,a, 'SIF‘PB4 - \A “‘5‘. so , 40 I. , 20 . Table 1.4: Partial and general equilibrium estimates of precautionary wealth (%) Model Partial Eq. (1) General Eq. (2) 100 x ((1) — (2))/(2) Baseline 44.92 30.09 49.29 Model 2 33.28 26.75 24.42 Model 3 76.03 34.08 123.11 Model 4 30.33 25.63 18.33 Model 5 60.36 32.07 88.25 Model 6 59.22 50.71 16.79 Model 7 39.34 11.81 233.19 17 Average Propensiliesb Save 0-5 ‘ r V i ' -1 r ' I T 7' r N l . 0 0 hi 0 - / u all; )1 it it "s. * K ‘ o if as 415 ~ 3., . \‘x -1 - -Model a \ 4 *Conventional ) ; -1.5 - oAlternafive a O\ .l \ r) i .2 . .1 _2.5 j I 7 . . I . . a. . f 20 30 40 50 60 70 80 Figure 1.5: Average propensities to save Table 1.5: Reproducing results: % of wealth that is precautionary Model Lifespan All Uncertain Certain HSZ 1 68.29 71.93 HSZ 2 67.17 70.97 Skinner 1 47.86 50.87 Skinner 2 47.04 50.13 18 90 MeanWiY Ratio Figure 1.6: Wealth/income profile: Baseline model Wealthllncome profile: Baseline Model 18 ' r I l'—' I r 16,» 14. 12 ~ 10 r - BaselineVarianoe r—1IZBaselineVariance 8 6 4 2 0 , I . . -. . , .. 20 30 40 50 60 70 A96 Table 1.6: Partial vs. general equilibrium effects Model % prec. % Prec. 100 x % prec. % Prec. 100 x ((1) - ((3) - (2))/ (2) (4))/(4) PE. (1) GE. (2) PE. (3) GE. (4) HSZ 26.63 22.38 19 30.33 25.64 18.32 Skinner 41.62 27.63 50.67 44.6 31.06 43.59 19 Figure 1.7: \Nealth/ income profile: Model 2 Wealthllnoome profile: Model 2 25 T , ' ~- . . TI 20 «a a! a... 0 .~ ineyananoe -- : aselmeVananoe MeanW/Y Ratio Age Table 1.7: Selected capital output ratios Interest Rate Saving Rate .03 .04 .05 .06 .16 6.7 5 4 3.3 .18 6 4.5 3.6 3 .20 5.3 4 3.2 2.7 .22 4.7 3.5 2.8 2.3 .24 4 3 2.4 2 20 MeanWN Ratio Figure 1.8: Wealth/ income profile: Model 6 WIWmeprofileModelfi 18 -. » - . . — . . . . . 16 ~ 14i- i 121» 10$- - BaselineVarianoe -1IZBaselineVariance Br- 6 ~ , 4 __ //.x' J” ...a/ 0 . . M .. 20 30 40 50 60 70 Age 21 Figure 1.9: Age-wealth profile: Stochastic and deterministic economies Age-Wealth Profile: Stochastic and Debuninisfic Economies 140 . T . r . . 120 ~ -All Stochastic - Lifespan Stoch. 100 Assets “8 8 8, S r09--. 22 90 Chapter 2 Green taxes and double dividends in a dynamic economy 2. 1 Introduction The possibility that green tax reform may yield a double dividend has become a ma- jor issue in the environmental policy arena. The double dividend hypothesis is nicely exposited in Goulder [1995] and Bovenberg [1999]. Apart from decreasing pollution externalities, a ‘green’ dividend, environmental taxes raise revenue that can be used to lower other (pre—existing) tax distortions, resulting in a smaller deadweight loss from the tax system, or ‘efficiency’ dividend. Because of the appealing nature of such reform Bovenberg calls environmental taxes a ‘no regret option’. Most of the work on the double dividend problem addresses the question from a normative perspective and in a static framework. Examples include Bovenberg and van der Ploeg [1998], Carraro and Soubeyran [1996], Holmlund and Kolm [1995], and Koskela et al. [1998]. In an influential paper, Bovenberg and de Mooij [1994] use a model with two goods (one clean, one ’dirty’), and labor as the only input, to examine whether increasing the tax rate on the polluting good above its Pigovian level, and reducing labor taxes in a revenue neutral fashion will deliver a welfare gain. In this version of the double dividend question, the distortionary effect of increasing green taxes above the level at which the marginal pollution damage is internalized should be compared to the efficiency gains from reducing other taxes. Bovenberg and De Mooij 23 find that the efficiency dividend does not materialize, since green taxes turn out to be more distortionary than the labor tax by virtue of their effect on the composition of the production bundle. The previous result relies heavily on the static nature of the model. A few papers have extended the discussion to a dynamic setting. Bovenberg and de Mooij [1997] study the impact of environmental tax reform on long run growth. In their model, where production externalities decrease the productivity of capital, a tax shift from output taxes to pollution taxes always achieves a green dividend, and an efficiency dividend is obtained only under certain parametric conditions. Perhaps the closest paper to ours is Bovenberg and Smulders [1996]. In this paper, the transitional dynamics of a growth model are examined after a tightening of environmental standards occur. Starting from a situation where green taxes are below their Pigovian levels, the authors study the conditions under which the efficiency dividend is obtained. This paper departs from previous literature on the double dividend hypothesis in that it examines a policy rather than a normative question. We are interested in the environmental and efficiency effects of green tax reform in the US. As Bovenberg and Smulders, we compute the transitional path after a policy change, but unlike their paper, the policy change in our experiment is a revenue-neutral tax reform, intended to address the double dividend question, and involves an actual calibration to the US economy. Unlike previous work, this paper focuses on the effects that the higher levels of capi- tal accumulation resulting from a more efficient tax system may have on environmental quality. After Lucas [1990], and Hall and Jorgenson [1967], a large body of evidence suggests that tax changes have a first order effect on the level of the capital stock. Moreover, this effect is important enough that we would expect it to overshadow the effects of pollution on productivity emphasized in previous work. Our focus on capital taxes is in part dictated by the mechanism we want to examine. By choosing to re- duce capital taxes, as opposed to labor or consumption taxes, we are maximizing the 24 efficiency dividend and therefore, by promoting capital accumulation, betting against better environmental quality. If it turns out that the green dividend is also achieved by decreasing capital taxes, then it will most likely be achieved by shifting the tax burden from any preexisting tax to green taxes. In our model, which is described in section 2.2, there are a large number of identical infinitely lived households. Households value clean consumption goods, dirty consump- tion goods, like gasoline, and their stock of health. Final goods and services are produced using capital, which is clean, and a dirty input, fuel. Fuel is produced with capital as the only input. Health is a function of the stock of pollution. Pollution is augmented by current fuel use, both in consumption and in production and depreciates like the other capital stock. The government collects taxes on fuel and on capital income. In the main policy exercise considered, increased revenue from green taxes is used to reduce the tax rate on capital earnings. As noted above, by choosing to reduce the highly distortionary capital taxes, we all but ensure that the efficiency dividend will obtain, and we focus on the environmental effects of the policy change. We find that, because a more efficient tax system encourages capital accumulation, the environment may worsen in the new steady state. However, in all the cases we consider, a double dividend is obtained during a very long period of time at the beginning of the transition. We conclude that a tax reform experiment of the nature explored in this paper is most likely to be Pareto improving. This chapter has four other sections. In section 2.2 the model is presented. III section 2.3 functional forms and parameter values are chosen, then section 2.4 presents the results, and section 2.5 concludes. 2.2 The model The economy is populated by a large number of infinitely lived individuals. We abstract from population growth and normalize population size to unity. Preferences of the 25 representative individual are given by 2 Hum, mar; 12,), (2.1) t:0 where C, is consumption of the single perishable consumption good at time t, ma is the amount of fuel consumed at time t and h, is the state of health at time t, B is discount factor which is a real number between zero and one, and u is felicity. We find it useful here to disaggregate consumption goods into two types: one good, which is associated with negative pollution externalities, we call fuel, in“, and the other good, which is not associated with such externalities we refer to as the consumption good, ct. The elasticity of substitution between these two (consumption) goods will play an important role in the following analysis. In the utility function specified in equation (2.1) the state of health, ht, enters as a separate variable. Health here is a capital stock, which is taken as given by each individual, but which depends upon the aggregate amount of pollution in the economy. The relationship between health and the aggregate amount of pollution, z,, is given by ht = h(zt). (2.2) The consumption good is produced via a constant returns to scale technology using two inputs, capital km and fuel mpt. The production function is given by y, = f(kpt, mpt). (2.3) Fuel is produced using capital km, only. The production function for fuel is given by m, = 9(kmt). (2.4) There are two capital stocks in this economy, physical capital (kt) that can be used in the production of the consumption good (km) or fuel (km), and the stock of pollution (at). These two types of capital evolve according to 514.1 = (1— (5)6] + ii) (2.5) 26 zt+1 : (1—— 6Z)zt + mt, (2.6) where it is investment in physical capital at time t. In this economy, fuel m, can be used as an input in the final goods sector, mm, or consumed, met. The initial endowments in this economy are kg and 20. The government in this economy collects taxes on capital income at the uniform rate 77,, and taxes on household fuel consumption and fuel use by firms at the rate Tm. All tax revenue is rebated in a lump sum fashion to the households. The representative household in this economy solves the problem max 2 ,Btu(ct, met; ht), (2.7) . e 30 ((1‘) A’f+117r)’Cf)t:0 ‘20 subject to 00 00 ZPthr +7} + (1 + Tmlwtmct) = Zl’tffl - Tklfhkt + 7rmt + TL)» t=0 t=0 kt+1:(1_ (ilk: '1‘ it: given k0) {7):,(1c,wt,hl}f:o, where pt is the price of final goods at time t, wt is relative price of fuel compared with final goods at time t, qt is return to capital at time t. Here mm are profits from producing fuel and T, are the lump sum transfers from the government. The final goods producing firm solves the problem max f(kp¢,mp¢) — qtkpt — (1 + T,,,)-'wtmpt. (2.8) {kph mpt} The fuel producing firm solves the problem III'CIX “Hf/(knit) — thtnta (2.9) mt We do not allow the government to run a deficit or surplus, so the government budget constraint each period is 27 T,,,-u.',,(mct + mm) + qu,kt = T,. (2.10) An equilibrium for this economy is an allocation for the representative household {chmch kpt+1,kmt+1}f:0, an allocation for the final goods producing firm {kpt,rr2.p,}j’f’__0, an allocation for the fuel-producing firm {k,,,,}f_:0 and prices [10,, q”, qmt},°:0 satisfying 1. the household’s allocation solves the maximization problem in (2.7), 2. the final goods producing firm solves the maximization in problem (2.8), 3. the fuel-producing firm solves the problem in (2.9), 4. the fuel and capital markets clear, and 5. the government budget constraint (2.10) is satisfied. 2.3 Calibration In this section we restrict numerically the model by choosing functional forms and parameter values. For the utility function, we need to choose a functional form that allows us to match the observed income elasticities for household fuel demand. In most standard utility functions, such as Cobb-Douglas or CES, the implied income elasticity is unity. Schmalensee and Stoker [1999] find an estimate of this elasticity of 0.2. Other estimates of this elasticity are in a neighborhood of 0.2 (Puller and Greening [1999]). To allow for varying income elasticities we pick the following utility function: 1 1_ 00"“ng + (1 — 9)772.£t)””)1‘0, ~11.(Ctamct; hr) = §>0,p>0,0<6<1,0 0, a < 1, 0 < x < 1. (2.12) The production function for fuel is Cobb-Douglas in one input capital, so that g(k,m) = 151.33,, 0 < a < 1. (2.13) Finally, the health production function is of the form, [1(a) = l/zt. (2.14) \Ne calibrate our model to the US economy. The benchmark parameters we use are illustrated in Table 2.1. Calibrating the utility function to long-run data is a bit tricky since preferences are not homothetic and expenditure shares do depend upon the level of income. We thus pick preference parameters E and p that match observed income elasticities at the steady state. Most estimates of this income elasticity are in the neighborhood of 0.2 (See Schmalensee and Stoker [1999]). But we experiment with higher and lower values for this elasticity. The elasticity of substitution parameter, Oz, in the CES production function is set equal to —O.5, making substitution between fuel and capital slightly more difficult than in the Cobb-Douglas case. The case of a 2 ~10 was also considered with no substantive change in the results. We choose a value for the preference parameter 77 that places a relatively small weight on health. Since health is not a choice variable for the household, the choice of 17 has an effect on the allocation only through the effect of fuel consumption me on future health levels. The preference and technology parameters {A,9, x} are chosen so that fuel usage by household out of total usage is 30% 1 and fuel share of GNP is 7% 2, and the 1The Statistical Abstract of the United States 1999, table 955 contains data on fuel use which is broken down into the following categories: residential and commercial, industrial, anti transportation. We assign 50 percent of fuel use in the residential and commercial category to fuel use in consumption. Over the period from 1970 - 1997, households used 30.75 percent of all fuel. 2According to the Statistical Abstract of the United States table 958 and table 727, expenditure on fuel as a fraction of GDP in the US for 1995 is about. 7%. 29 household’s expenditure share for fuel is about 3.5 percent 3. We know very little about the technology parameter 0). We execute some sensitivity analysis and find that our qualitative results are robust to changes in '1/1. We assume that the depreciation rate for capital is 10%, and we choose 6,, to be consistent with the steady state conditions. The Statistical Abstract of the United States 1999, table 793 contains data on the state tax rates for gasoline in 1997. Together with a federal gasoline tax of about 18 cents for a gallon, the average tax rate for gasoline is around 50% 2.4 Results To solve this model, we first obtain the steady state using a Newton-Raphson proce- dure, then we linearize the first-order conditions around the steady state and solve the resulting difference equations. The approximation errors that result are very small, as evidenced by the Euler residuals: 'II.(.(‘f.) 11,.(1 + 1);3(1 + n+1— 6) —1 shown in Table 2.2. We now report the results of our main experiment, a revenue neutral tax change. In this experiment, we raise the fuel tax and adjust the capital tax to keep the government share of GDP constant at 35%. For ease of exposition, we concentrate first on steady— state comparisons, and examine the transition path later. Figure 2.1 shows fuel usage in steady state as the tax on fuel increases for the baseline parametrization. It is clear from this figure that the steady state level of aggregate fuel consumption is not monotonic in the tax rate on fuel. In fact, fuel use by household is monotonically declining in the tax rate, as the substitution effect dominates the income effect because of the small income elasticity. Fuel use by firms, however, increases in the tax rate. This is an expected result, since higher tax rates on fuel are accompanied 3’This is slightly lower than the average share of household income allocated to fuel estimated by Chernick and Reschovsky [1997]. 30 by lower capital tax rates, and therefore higher steady state levels of the capital stock. When the fuel tax rate is low (high), the former (latter) effect tends to dominate, giving a hump shaped relationship between tax rates and aggregate fuel usage. The steady state levels of the capital stock as Tm changes are depicted in figure 2.2. While the amount of capital devoted to fuel production stays roughly constant, capital in the final goods producing sector increases as the tax on capital income is reduced and the tax system becomes more efficient. Figures 2.3 to 2.5 show the transition path from period 11 (time 1), when the policy change occurs. At time 1, the higher tax rate on fuel generates, via a substitution effect, a sharp decrease in fuel consumption (figure 2.3). The lower tax rate on capital earnings, however, creates incentives to accumulate capital (figure 2.4). Since capital and fuel are complements in the production of the capital good, fuel consumption by firms increases monotonically from time 1 (period 11). Figure 2.5 shows the evolution of GDP and consumption of the final good. At the time the policy change takes place and the rate of return to capital jumps, more capital is devoted to produce final goods kp, and the relative price of fuel must fall to avoid arbitrage opportunities. As capital is accumulated however, the relative price of fuel increases reducing the share of capital used in final goods production. This composition effect operates to reduce final goods consumption after period 11, but eventually the growth of the capital stock takes over the dynamics of this variable. Note that for a period of about 25 years (period 15-40 in figure 5) the household has a lower level of consumption of both fuel and the final good. We now turn to the welfare effects of this policy experiment. To disentangle welfare changes from different consumption paths and different health stock paths, we first compute the level of discounted utility during the transition to the new steady state, assuming that households enjoy the levels of health of the original steady state. we then calculate by what percentage should consumption (of both fuel and the final good) 31 increase for both discounted utilities (original steady state and transition) to be equal, and call this number the efficiency dividend. Next, we do the same exercise but now holding consumption at the level of the original steady state, and comparing discounted utilities where only the stock of health changes. We call this second number the green dividend. Table 2.3 shows both dividends for the baseline case, where Tm increases from .5 to .55, as well as for alternative tax changes. Note that the green dividend is obtained in all cases, but the efficiency dividend obtains only for target levels of the green tax below a critical level, around .5. Above this level, we conjecture, the green tax becomes more distortionary than the capital earnings tax, and the results mimic those in most of the green tax literature. Below this level, however, both dividends are realized. With the caveat that we know little about how health enters into the utility function, we can appeal to linearity and add both columns of table 2.3 to get the aggregate welfare effect. This effect is always positive, since the green dividend is always larger -by as much as two orders of magnitude in the baseline case than the efficiency dividend. Summarizing, even though in steady state comparisons the efficiency dividend always holds, and the green dividend is in doubt, the transition path shows that the a lower level of pollution will be enjoyed for a very long period during the transition. In order to build a larger capital stock however, a lower level of consumption must be endured for some years near the beginning of the transition. The green dividend, or higher discounted utility from a cleaner environment, will then always obtain, while the efficiency dividend, or higher utility from consumption of market goods, obtains under most, but not all tax changes. 2.5 Conclusion In this paper we have studied whether a green tax reform actually does deliver a double dividend in a model calibrated to the US. economy. Our answer is a timid yes. In our 32 model, raising a green tax does indeed allow a pre-existing tax to be decreased, here a tax on capital income. Cutting capital taxes stimulates investment and growth, so green taxation does yield one dividend. If capital and fuel are complementary inputs, however, increasing the capital stock raises the demand for fuel which can, depending on the degree of complementarity, offset any decline in fuel use due to higher fuel taxes. While this offsetting effect is important in steady state comparisons, it is dwarfed by substitution effects that decrease the consumption of fuel and thus deliver a better environmental quality for a very long period along the transition path. A green dividend is then always achieved, but the growth dividend is achieved only when the target level of the environmental tax is below a critical level. 33 Table 2.1: Benchmark parameters and data Ereference parameters ] ,1” 0.979 a 3 6 0.925 7) 0.9 f 0.83 p 0.17 ] Technology parameters [ Final good production 1 A .111 a -0.5 x 0.983 fluel production j E 1 1,6 0.5 [Bepreciation rate T] 6 0.041 1 6,, 0.1 [ Data , fig 0.3 mm / ('1’ N P 0.07 Table 2.2: Euler residuals (er) Change of tax rate on fuel max [er] .5 to .55 4.9 x 10“6 .65 to .7 3 x 10-6 .5 to .6 1.8 x 10‘5 .35 to .4 8 x 10‘ .3 to .35 9.4 x 10—6 34 Table 2.3: V‘Velfare analysis: Compensating variation (%) Change of tax rate on fuel Growth dividend Green dividend .5 to .55 -.008 .16 .65 to .7 -.026 .15 .5 to .6 -.0084 .33 .35 to .4 .038 .18 .3 to .35 .056 .19 Figure 2.1: Steady state comparisons: fuel mc(').mp(-).m(0) 0.4 T l l l I I T F I O O O o O O O O O O O O O o O O O C) o 0.35,; 0 - 03- E025- a O. E. U E 0.2— . 045- - it if 3! 0.1- ”g "f x a X * 3‘ )K 3* x X X M )K 3( X * * 3‘ 005 l l l l l 1 l l l O 01 02 03 04 05 06 07 08 09 1 tax rate on fuel Figure 2.2: Steady state comparisons: capital kpf').km(‘).k(0) NV 6 I I T T T T l T To 0 o x 003*" 03"! of?" 55 Ox 0)! Ox 0* 0* 4- 0“ 0" out A * % 0 3K §3~o dBK if 2.. 11- -< 0 111111 111 0 OJ 02 03 04 05 06 O] 08 09 mxmmonmm 36 Figure 2.3: TTansition path: capital k(-).km(0).kp(.) (1995 (199 M) (k km (1985 (198 (1975 tltttlttttrlttltn »:Iltctillttltl ~‘llillllll (lllltltlllllll .. “'llllll .tgnzlurttttlattrltltltl (197 0 10 20 30 40 50 60 70 80 90 100 penod 37 (m.mp.mc) Figure 2.4: Transition path: fuel mt).mp(-).m0(') 0.995 0.99 0.985 0.98 .......... ..........;:;: ........... .-.......-...;; ........... ...-,,,,._ ------------ -~--......:-:‘ - ----------- .............. ............... ............ 0.975 0 1O 20 30 40 50 60 70 80 90 100 penod 38 Figure 2.5: Transition path: GDP y(*).c(-) 1.0025 . and final goods consumption 1.002 c 1.0015 I 1.001 r (v.0) I 10005 0.9995 ‘ 0 40 50 60 70 penod 80 90 100 Chapter 3 Training and business cycles 3. 1 Introduction This paper studies the behavior of skill acquisition through training at business cycles frequencies. Beginning with Mincer [1974] and Porath [1967], human capital accumu- lation has been extensively studied as one of the main determinants of productivity growth along a worker’s life cycle. Human capital investment also plays an important role in accounting for cross country differences in growth rates in the empirical litera- ture spanned by Barro [1991] and Mankiw et al. [1992]. In an influential paper, Lucas [1988] suggests that human capital investment is the main force driving long run growth. While the literature on human capital accumulation on both the life cycle and aggregate growth dimensions is vast, we still have a limited understanding of the mechanics of skill acquisition over the cycle. This paper contributes to bridging this gap. Understanding the behavior of skill acquisition during the cycle has potentially im- portant implications. From a policy perspective, firms implement training programs -and workers engage in them— after deciding that future benefits in terms of higher pro- ductivity offset current opportunity costs. If training turns out to have a strong cyclical component, then the rate of return on the large number of government-sponsored train- ing programs might be affected by the time at which they are implemented. Moreover, the cyclical behavior of training may help explain both the phenomenon of procyclical productivity, and the empirical finding that recessions tend to be followed by periods of 40 higher than average productivity growth (see Bean [1990] and Saint-Paul [1996] ). In both cases, it has been conjectured that training occurs in downturns and the economy starts a new cycle with higher levels of human capital. Finally, we will argue that the behavior of skill acquisition is strongly linked with the ease with which firms can adjust their factors of production, so that the analysis in this paper will shed light on the cyclical behavior of employment, hours, and labor productivity. Our empirical knowledge of human capital investments during the cycle is limited to Dellas and Sakellaris [1996], who study skill acquisition activities through formal schooling. In that paper, a database of college enrollments is constructed and the cyclical properties of the series examined. The authors report that college enrollments are countercyclical, and strongly tied to local labor market conditions. The theoretical implications of skill acquisition activities are explored in a limited number of papers. DeJong and Ingram [2001] estimate a real business cycle (RBC) model with human capital production, investment goods and final goods sectors, and a rich stochastic specification. In their paper, the authors note that there is a lack of usable data on skill acquisition at high frequencies, and address this issue by using their model to infer what the behavior of skill acquisition should be given the realization of the remaining variables. Using a maximum likelihood procedure, they find that a countercyclical and highly volatile behavior of skill acquisition time provides the best fit of their model to existing data. Einarsson and Marquis [1998] show that adding human capital accumulation can improve the capacity of a model to match the low observed correlation between hours and productivity. A second paper, by Perli and Sakellaris [1998], shows that the coun- tercyclical allocation of resources from a goods producing sector to a sector producing human capital adds a strong propagation mechanism to the standard model. While these results are important, we believe that the ability to assess their empirical relevance is 41 hampered by lack of reliable data 1. This paper is closer in scope to DeJong and Ingram [2001] in that we are interested in the cyclical behavior of the types of skill acquisition that occur after workers leave formal schooling. In so doing, our study complements the work by Dellas and Sakellaris [1996], who focus on skill acquisition through formal schooling. This paper contributes to the literature in two ways. One, it is the first paper to construct a time series of training activities, and to document its cyclical properties. Two, it highlights the role of labor adjustment costs in explaining the cyclical behavior of skill acquisition. Our results show that training, both on and off-the—job, is weakly countercyclical, leads the cycle, and has a standard deviation of more than ten times that of output. We show that a standard RBC model with human capital accumulation is unable to reproduce this volatility, but a. model with empirically plausible adjustment costs of employment can. The rest of this chapter is organized as follows. Section 3.2 describes the data used and documents the regularities to be explained by a business cycle model. Section 3.3 presents the model. Section 3.4 calibrates the model, and section 3.5 presents the results. The last section concludes. 3.2 Data 3.2.1 Data description In this study we use the National Longitudinal Survey of Youth 1979 (NLSY79) as the source of training data. The N LSY79 is a longitudinal survey of 12686 individuals who are interviewed every year from 1979 to 1994, and every two years since until 1998. The 1The data on human capital used in Einarsson and Marquis [1998] and Perli and Sakellaris [1998] is a series constructed by Jorgenson et al. [1987]. To construct this series, at every period classes of workers are aggregated using both their wage levels (which are intended to measure the level of human capital) and relative weights in the workforce. While wages are at best weakly procyclical, it is well known that low wage workers drop out of the workforce in higher proportions during recessions, and return during booms. The resulting index shows a clear countercyclical pattern, but this is influenced by the effects of the cycle on the composition of the workforce, and it. is unclear to what extent it measures skill acquisition activities. 42 same respondents are followed every interview year without replacement, so that the age distribution of the sample ranges from 14 to 22 years in 1979 and from 34 to 44 in 1998. With this dataset we first construct a quarterly panel from 1978Q1 to 1998Q4, using questions on the incidence and time spent in training, the type of training provider, working status (working/not working), industry code, and education level (less than high school, high school and some college, college graduate). The questions on train- ing, however, are not consistent across time. From 1979 to 1986, the survey registers information on up to three training programs in which the respondent enrolled for more than one month since the date of last interview, and up to two programs in which the respondent was enrolled at the time of the last interview. In 1987 no training ques- tions were fielded, and in 1988 no information is recorded about training programs in which the respondent was enrolled at the time of last interview. From 1988, informa- tion is recorded on up to four training programs started since the date of last interview, regardless of the duration of the program 2. The questions on the type of training provider are used to separate training into On-The—Job (OJT) and Off-The-Job (OFFJT) training, a distinction that intends to separate firm-specific skill acquisition (OJT) from investments in general skills (OF - F JT). The assignment of training programs to either OJT or OFF JT is done according to whether the program took place at the workplace or not. Table 3.1 details how the different N LSY training categories are aggregated in On-The—Job and Off-The—Job training. Once the panel is constructed, there are 12,686 individuals, with each being observed for up to 84 quarters, or 1,065,624 observations in total. The NLSY79 oversamples the military population, and this subsample is dropped (107,520 observations). Further, 2To construct this panel, we consider a respondent to be in a. training program in any quarter if he was enrolled in training for more than one of the three months. For consistency between time periods, we use a maximum of three training programs per year for each respondent, which has negligible effects on the resulting series. 43 all observations prior to the respondent last being enrolled in school, and posterior to the respondent’s last interview are also dropped (414,976 observations) 3. Finally, we divide the sample into two subperiods to address the problem of data inconsistency, as explained below. A total of 543,128 observations remain, and are matched with business cycle indi- cators: GDP and Investment from the Bureau of Economic Analysis, and industrial production by 2-digit industry from the Board of Governors of the Federal Reserve System, for respondents who report working in manufacturing industries (SIC 20-39).4 Table 3.2 shows descriptive statistics for this data, and Table 3.3 describes the nomen- clature. This panel is then used to produce time series at different levels of aggregation: by education groups, working status, etc. The NLSY79 data has the natural advantages of a panel dataset over aggregated data, and for the purpose of this study it contains extremely detailed information on training at the individual level. There are also two potential problems associated with it when used to construct an aggregate time series. The first problem, as explained above, is that the data collection criteria for training questions previous to 1986 and posterior to 1988 are not entirely consistent. The second potentially important problem is that we observe the same individuals at every time period, so we must be careful to filter out life cycle effects. We discuss these questions in turn. To address the question of data consistency, we choose to divide our sample in two subperiods, and report our results separately for both. Additionally, we choose to keep in our time series only the periods with more than 3500 observations. Since about 3 to 4 percent of the respondents are enrolled in a training program in each period, this procedure mitigates sampling errors to be amplified in the time series. With these 3There is also an oversampling of the economically disadvantaged groups, and this subsample is kept, but weighted accordingly in the calculations of means, etc 4GDP and Investment downloaded from www.Economagic.com on November 10,2001. Two-digit industrial production downloaded from the Board of Governors of the Federal Reserve System’s web site (www.federalreservegov) on October 25,2001. 44 adjustments, we have two periods of valid data, one from 1979Q2 to 1985Q4 (Period 1), and 1989Q1 to 1997Q1 (Period 2). For the life cycle problem, we begin by noting that at any period a 9 year window of the age distribution is observed, and this cross sectional variation can be exploited in order to separate life cycle effects from business cycle effects. To do this we run a pooled regression of training variables (incidence and hours) on time dummies, that capture business cycle effects, and age and age squared, that capture life cycle effects. While we find, using an F test, significant coefficients for OF FJT that suggest declin- ing investments in general human capital, we find no such effects for OJT programs. With these results in hand, we choose to use the time series data without applying any transformation, other than logging the hours variables, and we will report the results for both types of training programs. 3.2.2 Stylized facts We now document the cyclical properties of the variables. The correlations with out- put (Table 3.4) of hours in production, investment and productivity display well known regularities: all variables are strongly procyclical, with the exception of labor produc- tivity in period 2. The correlations between the training series and other business cycle variables are shown in Table 3.5. The results are consistent for both time periods, and suggest that both OJT and OF F JT are countercyclical. Table 3.5b, computed using pooled data, shows that these correlations are statistically significant when estimated taking advantage of individual variation in the data. 5 A disaggregated analysis (not reported) reveals that this pattern is broadly consistent across education groups, with hours in training of higher educated workers showing stronger (larger in absolute value) negative correlations with output and investment. Only hours in off-the—job training (hofi ) in period 2 shows a weakly procyclical pattern. 5Note that the results from tables 3.5a and 3.5b are not comparable: table 3.5a uses log aggregate hours in training at time t as the training variable, while table 3.5b uses hours in training at time t for each individual. These results suggest that skill acquisition activities that would tend to make hours in on-the-job training (hojt) procyclical, such as those associated with the acquisition of new capital goods, are unimportant in the aggregate and are small compared to training activities driven by opportunity cost considerations. Cross correlations of output with investment, hours and productivity (Table 3.6), and training variables (Table 3.7) are discussed now. In our sample, hours are not a leading indicator, but show the strongest correlation with contemporaneous output. This is also true for investment and productivity, with the noted exception of output per hour (prodh) in period 2. Table 3.7 indicates that, while training incidence does not show a clear pattern (it lags output by 2 quarters in period 1, and seems to lead in period 2), the response of hours in training clearly leads output by as much as 3 quarters (HOJT, period 1). Finally, table 3.8 shows the volatility of aggregated variables. The standard deviation of the (log) hours in training variables is extremely high, as much as 17 times that of output and hours (see figures 3.3 and 3.4) . Note that this is not an artifact of training having a growth or life cycle trend. When detrended using a Hodrick-Prescott filter, the volatility of HA CG decreases to .137 and .174 for periods 1 and 2 respectively, and a regression of HA CC on year and year squared show insignificant (at 5%) coefficients for both subperiods. At any quarter, note that only about 4% of workers are enrolled in training pro- grams, and in average about 1.58% of aggregate hours are spent in training, so the proportionally large cyclical variations observed in training hours and incidence need to be weighted by these scaling factors. But even with this caveat, the high volatility of training hours makes training a margin with an importance of the same order of magnitude as employn‘ient in adjusting aggregate hours. 46 3.3 Model In section 3.2 we presented a description of the high frequency regularities of the training series. Some of these regularities, such as the high volatility and moderate correlation with the main cycle indicators, are stark and defy obvious explanations, hence providing a test of high power that can be used to discriminate among competing models. A natural place to start is the model by Lucas [1988], where human capital accumu- lation is the driving force of long-run growth. A close examination of this model, or a RBC version of it (see Appendix B), shows that it fails along important dimensions. In particular, it cannot reproduce the high volatility of skill acquisition hours, it tends to produce too high degrees of countercyclicality, and fails to match the observation that training leads the cycle. The standard RBC model with human capital fails to reproduce these facts because, we believe, it does not incorporate the frictions that make some dimensions of labor input, such as employment or weeks worked, much costlier to adjust than others, such as hours per week. In this vein, we will explore the hypothesis that this high volatility of the training variables is driven by the difficulty in adjusting employment at business cycles frequencies due, for instance, to the existence of hiring and firing costs. This difficulty creates a labor hoarding effect, so that the marginal product of labor is adjusted partially on the extensive margin -employment or weeks worked- but mainly on the intensive margin of hours devoted to work / skill acquisition. To examine this hypothesis, we construct a model where it is costly to adjust the number of weeks worked every year, while marginal adjustments in hours per week can be done at the prevailing wage. we do this in the spirit of Bils and Cho [1994], who examine the behavior of employment, hours and effort over the cycle. In this model, firms produce a single good using a Cobb—Douglas production function K : AtK?(ltNth)l-O. (3.1) 47 Here Y is output, K is capital, N is weeks worked per quarter, 1 is hours per week devoted to work, and H is human capital. A, a measure of total factor productivity, is a random variable that follows an AR(1) process: At+1 : p/It + ff 6! N 1’V(0, 062). (3.2) To produce, firms hire capital and efficiency units of labor [N H , and pay the costs of adjusting weeks. These costs take the quadratic form: B[N, — NH]2 C(AAQ) = 2 (3.3) The existence of adjustment costs implies that the firm faces a dynamic problem when it chooses employment, and it may incur negative profits at time t. While this cost structure is standard in studies of aggregate employment dynamics (see Hamermesh and Pfann [1996] for a survey), there is strong evidence that it is a poor approximation of the structure of labor adjustment costs at the firm level. At least two features of such a structure are absent in (3.3): (a) a fixed cost of adjusting, that drives a pattern of lumpy adjustment at the firm level 6, and (b) asymmetric costs of positive (net hirings) versus negative (net layoffs) changes. The lumpiness in adjusting employment, however, disappears once data is aggregated over firms (see Hamermesh [1989]). Since we do not have a panel of firms that would allow for modelling the firm’s decisions when facing fixed costs of adjustment, and then aggregating over firms, the approach in this paper is to use “reduced form”-equation 3.3- to interpret aggregate labor market observations. We believe that this approach is useful, in that the main mechanism that drive our results, namely the relative difficulty of adjusting employment versus hours, is explicitly modelled. The second feature of the firm-level structure of adjustment costs that is missing in our framework is the asymmetric nature of these costs. The evidence surveyed by 6This first point is most clearly made in Hamermesh [1989]. In a study of seven large plants, employment was found to adjust only after deviations of actual output from expected output reached 60%. Using a flexible parametric specification, the author reports significant fixed and marginal costs of adjusting employment. The same qualitative results were found in a study of airline technicians (Hamermesh [1992]). 48 Hamermesh and Pfann [1996] suggests that firing costs are larger than hiring costs, and that this asymmetry might still be present in aggregate data. We believe that, although the question is important, it goes beyond the scope of this paper, given that our dataset does not allow for observing firm-level data. If we let 7‘, be the interest rate net of depreciation, and using the conventions r0 = 0 and R, = 1', + 6, the firm’s problem can be stated as: 00 t 1 max E0 2( H {Kf’Ht’ltthhZU i=0 r=ol+Tr ) (14t1{t(l(ltNth)I—a — 'IUtltNth [P1] I Art—N(_1 2 —R,I\,—B 2 ). Households have preferences defined over consumption {0,},321, weeks worked {Nt},°:l, and hours per week devoted to on the job activities: work plus skill acquisition activities {1, +71, Bil. The distinction between weeks and hours per week allow for the study of two margins of labor input with different cost structures. From the perspective of individual preferences, casual observation indicates that most workers choose an internal solution to their problem of allocating time resources on both margins. Moreover, data on the behavior of weeks and hours per week are available to restrict these preferences. The utility function is similar to that proposed by Bils and Cho: oo nt+lt)l+cp 1V,l+¢ U=E "'l'gc+mN,—(—— ogflio t t 1+“? 1+¢ ). (3.4) Equation 3.5 shows the law of motion for human capital. Human capital depreciates at a rate 61;, and is accumulated by devoting time to learning activities. The technology for producing it is in the spirit of Lucas [1988], although human capital is not used to produce more human capital, and the specification in 3.5 does not allow for unbounded growth. Given our focus on business cycles, these simplifications are sensible. Allowing for the level of human capital to influence the efficiency of training hours (Nmt) would only tend to increase volatility, via a feedback effect from human capital to training. ("It Aft ) 1+0 H. =H1—6 . tH l( H)+" 1+6 (3.5) 49 The household problem is then to maximize 3.4 subject to 3.5 and the budget con- straint 3.6: , [ I+tp fVl+¢ max 22):” fi’(log C, + ‘Iant-(T—uifi— + f——'—7) [P2] {CiaNtaltanta1"t+131‘1t+1}f:0 1+

1<. If convergence fails, adjust bequests with qo = q1,and 13 by letting bl = ,6 if K1 < K*, and ()2 = 13 if K1 > K*. For both solution methods the grid size for assets is set to 5 -10% of average asset holdings, and the convergence criterion is set to .003. Convergence occurs generally in 79 iterations. Using the policy functions, we then simulate paths for 10.000 agents and compute the statistics. The original version of this algorithm is discussed in Imrohoroglu et .11. [1999]. A.2 Solution method for the deterministic OLG model We solve the deterministic version of the OLG model by a method presented in Rios- Rull [1999]. It is a ’shooting’ method that uses the fact that the Euler equation can be expressed as: 1. , r —1/o 1+(1+ my >> MHHJ ("mm + (1)030 + 1))‘1/9 — (w, + q) l + r ,z3’(1+r))‘1/9 1+r at = { }(lt+2 +{ } 1. Set technology and preference parameters, {(1.1 = a, a, 6, 6, 6} and guess levels of aggregate capital K0 and per capita bequests qo. 2. Using K0, and given the production function F (K, L) = AKC‘LI‘“, find prices {13w}. 3. Using the fact that “1+1 = 0, guess a value for (17‘, and compute {(11}le backwards using the Euler equation. 71 4. Check whether (11 = (1., otherwise go back to 3 and modify guess for (LT. 5. Calculate aggregate capital K1 and per capita bequests q1 using {at};r=1. If con- vergence fails, set q0 = q and K0 = K1, and go back to 1. 72 Appendix B Standard RBC model with human capital Model Utility (1 — l, — 71.,)l"0 1 - 6 U = E, Z;3"(log c, — m t=0 Resource constraint 0 = AtK,“(Htlt)l_a — ct — K,“ + (1 — (5)19 Law of motion for human capital (711)“7 l 0 = —[[(+1 + Ht(1- (5”) + 8 Stochastic process for A At+1 = pAg '1‘ 6t 6; N N(0,0;2). 73 Table 81: Variable description H Human Capital K Capital [3 Discount factor ( Consumption 1 Hours at work 71. Hours in skill acquisition A TF P shock (5 Rate of depreciation of K (5” Rate of depreciation of H 74 Appendix C First order conditions in the household problem [P2] Problem: . , 1 W NW max 22:0 fi‘(log c, + 171N,m—t)— + f t ) [P2] {(it,N(,lt,'nt,l\rt+l,Ht+1}f_:0 1+¢ 1+¢ (”INOIH) .t. 0: —H +Hl—6 +,—— 3 1+1 1( H) 6 1+ 9 0 = TilthNtft + (I + T0117, — Ct — A7144. Lagrangian: (Tit +l()1+¢ + Nt1+¢ 1+ (0 1+ (15 n N, 1+6 +lltlHt+1— Ht(1— 5H) ' 8(_l+—)6_ +/\t[’lUthiNtlt + (1 + rt)kt — Ct — [17,44]} .6 = E, 2:0 6‘{ log c, + mN, First Order Conditions: (Ct) 0: l-At Ct (N,) 0 : _th¢ _ mw — At‘lllthlt + [116’th671tl+0 (It) 0 : mN,(l, + 71")? + AflUthNt (71,) 0 = —mN,(l, + n,)"7 +11.,eN,0Hn[9 “((+1) 0 : "(\1 + [fEtAtHu + NH) 75 (Ht+1) 0 = _/l‘t + (13(1 — (SillEilltH — Ez/\t+1'll’t+1N1+llt+1 (At) 0 = ”(llthNtlt + (1+ 7})11} — Cf —' kH-l (“vtNtlHo (fit) 0: —f[(+1+Ht(1—(S][)+€ 1+0 76 Bibliography Economic Report of the President. United States Government Printing Office, 1999. Abowd and Card. 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