AN EXPERIMENTAL STUDY OF THE EFFEC‘!’ OF _ DlFFEREN‘f DEGREES OF “COGNI'EEVE STRAIN” ON CGNCEP‘E IDENTIFICAHON 110 663 Thesis Po: the Degree of Ph. D, MlCHlGAN STATE ’umvensnv Charles Richard Harper" 1963 THESYS ll iiiiiilii \\\\\\l\ 3 _12 This is to certify that the thesis entitled - i All EXERWAL STUDY OF THE EMEGI' OF DIFFERENT? DEGREES OF "CCBNEIVE #347:er @N CONCEPfir-zmIFICAT ION , -.._...._.......-.. g: ‘ presented by 4-,.- - ..- -~u -— "gin-p-‘A- _. - w-“”~—-\--. ~-..‘— - ,: "final-2:8. Richard Harper nu . a... n-vv \— ue. . J. - . -— sm-a — on..- has been accepted towards fulfillment {2 of the requirements for ‘5 Phil)“. r" degree in Educational Psychology 5 .- Major professor Date JuJy 24, 1963 0—169 PLACE IN RETURN BOX to remove this checkout from your record. TO AVOID FINES return on or before date due. DATE DUE DATE DUE DATE DUE MSU Is An Affirmative Action/Equal Opportunity Inuitution ($11!:an $9.1 ABSTRACT AN EMBIMEM‘AL STUDY OF TIE EFFECT OF DIEEEREM.‘ IEGREES T "GCBNITIVE STRAIN“ ON COME?! EEM'EICATION By Charles Richard Harper A search for an explanation of variations in effectiveness at presentation sequences used as guidame in the concept identi- fication task initiated the present investigation. The amount of "cognitive strain" induced by the sequences was postulated from past resem-ch as a possible explanatory principle. "Cognitive strain” was defined as stress on the cognitive schema and it was twpcthesized that an inverse relationship exists between "cognitive strain" and concept identification. The effect of levels of intelligence was also tested to determine their relationship to correct concept identification. Subjects were students of three classes of Introductory Psycholog who were asked to write a rule identifying the intended concept after viewing a sequence of slides containing gemetric figures, which were projected on a viewing screen. The rule was explained as the values of two dimensions that occurred more than once in a particular sequence. The Eccentric figures varied in four dimensions and on four values in each dimension. Charles Richard Harper Degrees of "strain" were created by manipulating (a) total amount of information presented, (b) amount of interposing information and (c) amount of information stored during a problem in a series of slides. Each subject responded under all. five degrees of "cognitive strain" . Identifications were scored for the mmber correctly made by eaCh subject. An analysis of variance of the main effects of group membership, intelligence levels, and presentation sequences was made with repeated measzn'ements on the sequences. The results showed a decreasing number of concepts correctly identified in each sequence when the latter were ordered for increasing "cognitive strain" . Differences were statistically significant for the comparison of adjacent sequences in three of the possible four comparisons. The data supported the hypothesis of an inverse relationship existing between amount of "cognitive strain" and effectiveness in concept identification. The hypothesis that a positive relationship between intelligence and concept identification would be found also appeared statistically warranted. No significant interactions between the main effects were discerned. AN EXTERJMBM'AL STUDY OF THE EFFECT OF 13mm memes OF ”COGNII‘IV‘E STRAIN" 0N COMEH‘ MMIFICAIION By Charles Richard Harper A TmSIS Suhnitted to MICHIGAN STATE UNIVERSEY In Partial Fulfillment of the Requirements ' For the Degree of DO'JTCR OF PHIHBOPH! GOLIECE OF EDUCATION 1963 (73%be 811N404 ACKNOJIEDGMEM‘S The writer wishes to express his gratitude and appreciation to Dr. Bernard R. German for his encouragement and guidance during the planning of this study and the preparation of this thesis. In addition, the author is grateful for valuable criticism and suggestions received from Doctors Harold J. Dillon, Don Hamachek, M. Ray Dentsr and Charles F. Wrigley. Finally, a special debt is owed to the members of the Introductory Psychology classes at Flint Cornmunity Junior College the participated as the subjects in the study. ii TABIE OF CONTENTS MMWMSOOOOOOOOOOOOOOO mmTABmSOOOOOOOOOOOOOO. Chapter I. II. III. IV. V. mmUGIIONOOOOOOOOOOOO. The Problem limitations of the Present Study REIATEDIESEARCHoe........o The General Hoblem of Concept Identification Smary of Related Research HIPCI‘IESESMDRATIONAIE . . . . . . . TIEEXPERMM............ Develoment of Five Sequences Design and Preparation of Slides Subjects ' Equipnent Recedtn'e ANAIESISOFIESUITS.......... Asstmptions Results Significant Factors SW AND DISCUSSION OF FINDINGS . . Interp'etattion of Findings WWKOOOOOOOOOOOOOOOOOOO BEHMOOOOOOOOOOOOOOOO Page iv 83 34- 4'7 52 63 LISI‘ W TABIES Table 1. Mean timber of Concepts Identified and StandardDeviations............. 2. SmaryofAnalysisofVariance........ 3. Graph of Mean Number of Concepts Identified as Sequences.................. 4. Duncan's Multiple Range Test of Sequences . . . 5. Graph of Mean Number of Concepts Identified at Intelligencelevels............. 6. Duncan's Multiple Range Test With Kramer's Modification for Unequal n's of Intelligence 137913 00000000000000.0000 iv 6 CHAPTER I INTRCDUCT ION In order to identify a concept a person must abstract or infer from the sensory data available to him and from his past experiences. He must focus on cannon features of repeated stimuli and recognize them as essential instances of the concept to be identified. The process of abstraction or inference in concept identification is, thus, basically that of distinguishing the relevant infomation in stimulus situations 0 However, sane irrelevant information is always present and must be handled by the learner. Although irrelevant information does not directly identify a concept, irrelevant infomation can be information-giving in terms of defining what a concept is not. The mount of information, both relevant and irrelevant, and the sequence in which information is presented can be manipulated by a teacher. Teaching, therefore, in this context can be considered as the use of procedures intended to facilitate the complex sorting task the learner faces and the general question arises - "What conditions determine the effectiveness of a presentation sequence in the guidance of concept identification?” /‘l The Problem A specific answer to the general question was evolved from the conclusions tritten by Bruner, Goodnaw and Austin (2) . In their investigations, they were concerned with the strategies problem solvers use in attaining concepts and suggested that different types of instances and orders of presenting instances will either increase or decrease "cognitive strain" . (*) The latter term was not given an Operational definition by these authors . The term "cognitive strain” (**) denoted a hypothetical construct and was used in the present study to suggest an inferred intermediate mechanism and is defined as "stress on the cognitive schema resulting from a noticeable increase in cognitive activity as a subject attempts to attain a concept." In the present study, anchor points by which the amount of I'cognitive strain”. can be ordered will be presented and it will be hypothesized that the effectiveness of various presentation methods used in the guidance of concept identification is explained by the degree of "cognitive strain“ each of these methods entails. The value of understanding the relationship between "cognitive strain” and concept identification lies in its being a more direct (*) ”Cognitive strain" will always appear in the text in quotations to signify that this is a hypothetical construct. (*r) Cattell has defined a “law of cognitive-(Innis investment strain. Increase in the number of intermediate cues an! subgoals in reaching a goal, as well as increase in the fineness of cognitive discriminations to be maintained, and increase of the length of time that intermediate, anticipatory mental sets (deferred action to ones) have to be maintained, occasion a strain of total cognitive-dynamic energy.” (3) Cattell's definition was formulated to apply to a different context, that of personality theory. .3- basis for determining the effectiveness of concept identification as compared to analyzing the characteristics of a stimulus. The characteristics of a stimulus only influence cognitive activity and thereby indirectly vary the effectiveness of concept identification. gatfiions of the Recent Sty Investigation of the process of identification of elements cannon to a class of objects may be unreliable because of the difficulty of controlling the subjects' past experience. However, the categorization-3 employed in identification of concepts may be considered as occurring at a perceptual level std a conceptual level. The principal difference between the two levels is in the inmediacy to experience of determining fitness of attributes to categories (2). It is possible to study categorization at the perceptual level and reliably evaluate the process by using tasks sure to be familiar to all subjects. By evaluating the process at the perceptual level, it was assumed that inferences about the processes of concept identification at the conceptual level could also be made. The observations made in this present s'tlxly were at the perceptual level and used a concept identification task with familiar, read.in distinguishable features. The tasks used in the present investigation were all instances of a conjunctive concept, a type of concept in which all objects of a class —- in this case ”correct" identifications - share cannon charac- teristics. Instances of the concept were varied on four dimensions ani on fom: values of each dimension. Dimensions are the attributes of .4. features of an event that is susceptible to same discriminable variation. The variations of the dimensions are called values. In each of the problems used there were two relevant dimension values to be identified. Relevant dimension values are the values of the dimensions that define a concept in a particular instance as compared to the irrelevant values which are contained in an instance but which do not identify a correct concept. The experimenter selected the order of the instances and the rate at which the instances were presented, as well as the length of time they were exposed. The subjects were instructed as part of the directions that each instance to be presented would contain one or two relevant dimension values. No information on the ”correctness” of identification was provided by the experimenter. These special characteristics of the tasks used to explore the relationship of "cognitive strain" to the effectiveness of concept identification all limit the inferences that can be made of the experiment to be reported in the chapters that follow. CHAPTER II MUTE!) RESEARCH The basic purpose which motivated this investigation was to discover I'what conditions determine the effectiveness of a presentation sequence in the guidance of concept identification?" Early attempts by educational psychologists to attack this problem are exemplified by the work of Pechstein (J3) and Hanawalt ('7). They, and others, investigated the presentation problem in terms of ”wholes" and "parts" but their evidence gave quite contradictory results. The contradictory results m have arisen because of the failure of the early experimenters to arrive at a definition of "wholes" and ”parts" which could be applied over a wide range of tasks. 0:: the failure to obtain consistent findings may have been caused by the experimenters' exclusive concentration of the stimulus to the exclusion of any consideration of mothetical cognitive recesses. But whatever the correct explanation, the "whole-part” approach to explaining the effectiveness of various presentation sequences became stagnated. In Underwood's opinion “the reason for this is probably that no canprehensive hypothesis concerning the variable has been set up by which the success of the studies m be evaluated ." (l7) T Problemofc e Ident c o In the early 1930's, K. L. Smoke (14) conducted a series of experiments in which concepts based on geometrical designs were to be given names. in example would be a triangle with a line at right angles extending firm the shortest side which was to be identified as a ‘mib'. Triangles with lines extending fran other sides were not “Elbe“. Smoke felt that the chief divantage in the use of non- representational diagrams in investigating concept identification was that it avoided the influence of previous learning that would be confounding if more meaningful concept problems were used. later studies, inclining the present one, have followed Smoke in this _ practice. In Smoke 's investigation, examples of the concept to be identified were referred to as ”positive or negative instances”. A. positive instance was defined as a stimulus canplex which contained all of the relevant characteristics of the concept of which it was an example. A; negative instance was a stimulus complex which did not present an or all of the essential elements of a given concept. Bach presentation contained a positive or negative sign to inform the subject of the kind of information that instance contained. From the results of his experiments, Snob concluied that there was no significant statistical evidence on which to conclude that concept identification proceeds either more or less rapidly when the series of emples used to develop a concept contained both .7- pmitive and negative instances than when it contained only positive instances. The criterion of effective learning was mount of time used to identify a concept. Smoke '3 conclusion was the basis for many later studies on the relative effectiveness of the presentation of positive and negative instances. Of these studies, a report by Hovland and Weiss (9) is of special relevance to the present investigation. These experimenters used Veigl-Itype cards and flowered designs varying in form, color, quantity and size which were displayed by 3" x 5” cards on a table for five seconds with twenty seconds allowed for the subjects to identify the concepts. Hovland and Weiss presented evidence that the exclusive use of positive instances was superior to the presentation of only negative instances and that a combination of positive and negative instances in a learning series was intermediate in effectiveness. In discussing their findings, the authors pointed out that a major research task remained -- that of determining the conditions responsible for the mater effectiveness of positive instances. In an earlier investigation, Hovland (8) alone had suggested that “separate analyses must be made of . . . the process of assimilating information fran the two types of instances when the amount of information transmitted is equated". Hovland and Weiss's conclusions substantiate the need for an answer to the basic question of this investigation - "What conditions determine the effectiveness of presentation sequences in the guidance .8... of concept identification?” However, it was the interpretation of the conclusions of Bruner, Goodnow and- Austin (2) which led the investigator away fran further consideration of positive and negative instances to postulating that “cognitive strain“ might offer an explanation. Bruner and his oo-workers were interested in what went on within their subjects. In their investigations, subjects were shown cards which contained figures varying in color, shape, number of figures and type of border. In each problem the one "correct" concept was to be discovered by the subject fran a series of cards displayed to him. Two general methods or strategies were described as charac- terizing the process by which subjects arrived at the "correct " concept. In one, the "focusing” or 'wholist" strategy, the initial card as a whole was made the basis of a trial hypothesis by the learner. The subject's response made it appear, or the subject said, that he canpared the subsequent card with his memory of the original one , looking for the features the latter had in cannon with the first and ignoring other features. In the second, “scanning" or "pm‘tist' strategy, the subject would “bet" on one aspect of the original card, such as its color, as being the basis of similarity and hey to the concept. He then had to change his hypothesis whenever he met a contradictory instance and had to remember other features of the first card so as to form a new hypothesis. The subjects who adopted the focusing strateg did better on the whole than did the scanners, although they were equally affected by increased difficulty of the problem. .9- Bruner and his co-worlners concluded that the I'scanning" placed a greater demand on the subject 's memory and used the term ucognitive strain“ to describe the increased dependency on memory. It should be emphasized that it was the strategies used by problem solvers that were the main concern of the investigators and not the method of presenting infomation. The impwtant contribution of their analysis to the present study is the idea of I'cognitive strain” though this term was not defined 'nor was its relationship to concept identification directly specified. Bruner, Goodnow and Austin, then, stated that increasing the demand on the subject is memory produced increased amounts of “cognitive strain“. In examining the characteristics of concept identification tasks which could be manipulated by the teacher -- or the experimenter -- and which could be presumed to place some additional burden on the subject 's memory, the writer was led to consider three conditions that night more objectively increase “cognitive strain". These coalitions are: (a) the amount of information presented to the subject, (b) the amount of interposing information, and (c) the amount of information that must be stored during the course of a problem. Thus, one sttfly has drawn conclusions concerning the effect of an increase in the total mount of information presented for observation by increasing the amount of irrebvant information. Archer, Bourne and Brown (1) had subjects, seated before an oscilloscope screen, observe a series of moving geometrical forms. The figm'es could be circles or .10.. ellipses, large or small, bright or dim, steady or irregular in contour and they could be traveling rapidly or slowly across the face of the tube and in one direction or the other. (mly four categories were selected as relevant at am one time -- all others were irrelevant to the concepts to be identified -- ad the subject had four buttons before him. The subject attempted, by a combination of trial ani error and reasoning, to discover a correct concept. The results showed that difficulty was magmanted, with increases in irrelevant information, whether measured by time to reach the criterion of thirty-two successive correct responses or by the number of errors made. Another series of studies may be cited here to illustrate the effects on concept identification of interposing information. Hunt (10) designed an experiment to get data on the form of the ”information retention curve” as a function of the serial position of the information which was to be retained. The stimqu were geometric designs with dimensions and values of: type of figure (star, fleur-de-lis, '1', an! cross), shape of border (circle or square), color of figure (outline or filled in) arxl orientation of the "side panels" (0 - 180°, 45 - 225°, 90 - 270°, :35 - 315°). The side panels were rectangles extending out from the border of the design. The designs were dittoed and stapled into a book. Instances were presented by having subjects turn the pages of their books on a signal frcm the experimenter. In a seconl experiment, the amber of interposing instances was increased. In a. third experiment, the three key instances, which transmitted information over different dimensions, were presented at various positions in a .11.. constant length training series. The three experiments together presented a consistent picture of interposing information effects during concept learning. Hunt concluded that as the mmiber of instances interposing between the original presentation and the test series were increased, the number of errors in identification of concepts was increased. Finally, in an extensive series of experiments desigmd to explore the factors that control the efficiency of performance on the type of concept problems introduced by Smoke and later studied by Hovland, Glanzer (5) has advanced experimental definitions of the systematic operations carried out by subjects . conjunctive concept tasks were used with two categories, multidimensional, multiple- problem series and a specification of the number of relevant dimensions. In the first four of the series of six experiments Glanzer reported, the systematic operations of the subjects were viewed as consisting of the storage of dimension values and the selection of dimensions. To demonstrate the effects of "storage load" and ”selection load" , an index for both was developed using perceptual data Glanzer had recorded in a separate experiment in 1961. Glanzer measured perceptual difficulty and assumed that values which were difficult to perceive under short exposure would be difficult to store under ample time exposure. The indices were used to construct eighty conjunctive concept problems equally divided in the following four categories according to the load imposed on storage and selection: low storage .12.. load, low selection load; low storage load, high selection load 3 high storage load, low selection load; high storage load, high selection load. The results showed that increases of load on either the storage function or the selection function decreases the efficiency of concept work. No interaction appeared between the two factors. Storage load was found to have a considerably greater effect than that of the selection 10$ 0 01' most significance to the present study was the development of indices of storage and selection loads whereby the investigator had measured "cognitive strain" , and his suggestion that an experimenter can obtain load estimates that will give a basis for manipulating load on the basis of assmnptions about the subject 's encoding. In the present experiment, it is the quantity of information that a subject must encode that is the assumed basis for varying "cognitive strain”. 8 ofRe tedRese h A type of concept identification problem was introduced by Smoke (11.) and studied by Hovlani (8,9) that classified examples as either positive or negative instances. The effect of using positive or negative instances in presenting concepts to subjects was evaluated but the reason for the superior effectiveness of positive instances was not determined. In attempting to study the strategies used by problem solvers, .13.. Bruner, Goodnow and Austin advanced the idea of ”cognitive strain“ aid this appeared to hold pranise for explaining the earlier findings. The literature on the concept identification problem suggested that three conditions, each of which had been studied in isolation, might provide the basis of a more Operational definition of "cognitive strain“. These conditions were: (a) the amount of information presented, (b) the amount of interposing information, and (c) the mount of information to be stored dining the solution of a concept identification task. CHAPTER III HIPOI'ESES AND RATIONAII 0n the basis of a review of the literature, it can be argued that methods of presentation designed to cause different degrees of ”cognitive strain“ will, in turn, result in different degrees of effectiveness in solving concept identification tasks. In effect, this way of putting the proposition related the effectiveness of guidance in concept identification to activities assumed to occur within the subject and is, in this sense, a phenanenological explanation. Its advantage is that it offers a more direct basis for understanding the effectiveness of alternative presentations than the analysis of only the stimulus characteristics of the presentations, since these characteristics only create conditions which affect the cognitive activity of the subject 0 Certain assumptions must be made in advancing a hypothesis based on this argument. They include a belief that all information given to a subject in the course of a concept identification problem will be considered relevant by him and that he will attempt to retain all such information until its relevance is confirmed or disconfirmed. Until sane basis for discarding information is given to him, a subject cannot know what information is relevant or irrelevant and must treat all information observed in connection with a task as necessary to .14.. .15- its solution. Any increase in the mount of information to be observed and retained by the learner, and any delay by interposing instances in the presentation of confirming instances may be expected to increase the cognitive activity. A. noticeable increase in the cognitive activity required in a problem will produce "cognitive strain” for the cognitive activity will approach the cognitive capacity of the individual. Under the conditions of I'strain", the individual will not function effectively. In a task of identifying concepts, as the individual's capacity is approached , the individual under ”strain" no longer has sufficient comtive energy available to attend to additional information which is available and actually relevant to solving a problem. Without cognitive emery available, the assimilation of information which is actually relevant to a decision does not occur, and does not enter the learner's cognitive realm for use to make a correct concept identification. In addition, as the individual under the "strain“ to make a decision acts, he makes a decision using information which is actually irrelevant but which he already has within his cognitive realm. A decision using actual irrelevant information is incorrect. As the “cognitive strain” increases, the mount of incorrect decisions increases, resulting in an inverse relationship between ”cognitive strain” and concept identification. The mount of “cognitive strain" in a given concept identi— fication task will be affected by the capacity of the individual. ~16- Ln indirect measurement of cognitive capacity can be approached through the use of a standardized test of mental ability since such tests are developed to evaluate the ability of individuals to deal with concepts and symbols (16). In am given experiment in concept identification, the expectation would be that persons scoring high on such tests would be more successful than those of lesser ability. Unless such a relationship were obtained, one would have to question the validity of the tasks used -- or of the mental ability test. While “cognitive strain“ occurs within the individual and cannot be directly observed, the manipulation of presentations will effect “cognitive strain” as demonstrated by Glanzer (5) . There are three conditions which may be manipulated to create different types of sequences of presentations and which will increase "cognitive strain“. First, as the total mount of information that is presented is increased, the learner will attempt to use all the information to the effect that there will be a noticeable increase in cognitive activity which results in “cognitive strain" . Second, an increase in the mount of information observed between the original observation of a stimulus complex and the use of the stimulus complex causes a noticeable increase in cognitive activity to handle the interposing information with the result that "o ognitive strain“ is increased . .17... Finally, an increase in the mount of information stored during a problem mm cause a noticeable increase in the cognitive activity, resulting in ”cognitive strain“. These considerations suggested the following hypotheses which becme the basis of the experiment to be described: Hypothesis I - There will be an inverse relationship between the number of concepts correctly identified and the mount of "cognitive strain" induced by increasing the mount of (a) information presented, (b) interposing information and (c) information stored during a problem. Hypothesis II - There will be a positive relationship between cognitive capacity, as indirectly measured by the Otis Quick Scoring Mental Ability Tests, and the lumber of concepts correctly identified. Several procedures were used to randomize and counter-balance extraneous variables which are described in the two chapters that follow. The control procedures will prevent interaction effects i‘rm being significant. GHAH'ERIV rm HERE]! Verification of the Impotheses was undertaken by conducting an experiment in which subjects were given the task of identifying concepts involving geometric figm-es presented in a series of projected slides. Subjects were told that the experiment was a task in remembering and that they would observe either two, three or four slides. The figures to be used were demonstrated and described as varying on four dimensions and that on each dimension four values were to be used as follows: Dimensions Zhluas Form Circle, triangle, cross, square color Orange, geen, black, red Size large, medium, small, tin Quantity me , two, three, four The attention of the subjects was directed to two pairs of horizontal lines appearing on the viewing screen. Instruction inclmied the information that the narrow horizontal lines on the screen were the height of the “small." shapes. Shapes that were not as tall as the narrow lines were ”tiny“. The wide horizontal lines were the height of "medim" shapes. Figures which were larger than the wide lines were "large". -l9- Preliminary testing with figures differing in three values of shapes, number and color resulted in a uniformly high mount of correct concepts identified. To increase variation in the nmnber of concepts identified, the number of values was increased from three to four and a fourth dimension was added. The addition of a. border dimension was tried. During trials with a border, it was discovered that this dimension required the shift of attention as in attending to a seconi separate figure, unnecessarily confounding the problem. In order to eliminate the need of a shift of attention, size, which is an integral part of the stimulus figure , was substituted for border as the fourth dimension. Preliminm'y trials also disclosed that the instructions were ineffective in getting subjects to record the specific value of a dimension instead of just the dimension to identify the concept. To eliminate the lack of response specificity, one exmple of each type of sequence was displayed during the instructions to the subjects and a smple response sheet was projected so that the correct method of recording dimension values could be demonstrated. After viewing a slide sequence, subjects were asked to write a “rule" identifying the concept. It was explained that the “rule" should identify the two dimension values that occurred more than once in a series. Subjects were instructed not to make notes and color blind individuals were identified so that their responses could be eliminated from the evaluation of the experiment. fivelognt g Five Semncgs The three conditions that were hypothesized to cause "cognitive strain" were applied to the arrangement of examples in a series. Five different types of arrangements of exmples were developed and each was labeled as a type of "sequence". The five different types of sequences created five different degees of ”cognitive strain". The construction of the five types of sequences was based on the assumption that a subject will attempt to use all information available to identify a concept, that he will not make errors in perception, that once a correct identification is made it will be maintained, and that deviations frm the ideal use of information will be no greater for one type of sequence than for any other type of sequence. The mount of relevant information in all types of sequences was equal. Sequence I - Lem ”Cognitive Strain' - To provide the least mount “strain“, a series of slides was prepared, each of which consisted of two slides. Both values of the concept to be identified were resented on each of the two slides. .21- Mile of Seguencg ; First Slide Second Slide Open Figures Denote Red Concept: Red - small The total mount of information (in the exmple, the six values - red, mall, one, circle, three, square) was at a minimum. There were no interposing slides between the original exposure of the concept and its confirmation. Thus interposing information was at a minimum. The mount of information that must be stored during the solution of the problem was the four values of the first slide and was at a minimum. Sequence II - Intermedige-Low ”Dani-tin Strfl" - To provide an intermediate but low mount of ”strain“ , series of slides were prepared, each of which consisted of three slides. The first slide resented one value of the concept, the second slide both values in combination and the last slide the other one value. (*) letters were etched on projection window between appropriate guide lines. “8" indicates small, "M' indicates medimn. Examples are two-thirds of actual size. -22- leof nceI* First Slide * Second Slide lest Slide Open Figures Denote Red Solid Figures Denote Black concept: Red - small There was an increase in the total mount of information to ten dimension values for Sequence II as canpared to the six dimension values in Sequence I. In the example, the six values present in Sequence I were increased to a total of ten values in Sequence II by the addition of the four values - two, medim, cross and black. The same minimum interposing information existed for Sequence II as for Sequence I since there were no interposing slides between the initial presentation of an intended value and its confirmation. The mount of information that must be stored until the final (*) In describing the construction of the five sequences, the identical concept identification task has been used for purposes of clari- fication. In the actual experiment , different tasks were involved as explained in the design anl preparation of slides. 43- confirmation was increased from four to seven values with the addition of the third slide. In Sequence I the four values of only one slide must be stored until final confirmation. In Sequence II, the values of two slides must be stored before the final confirmation. Although each of the first two slides presents four dimension values, one of the values in this sequence occurred in both the first and second slides (in the ample it is the value red). The effect is that a total of seven values was required to be stored in Sequence II, which is an increase fran the four values required to be stored in Sequence I. Sequence III - Mgmdigte-Medig ”Ogfltive Strgg" -- To provide a further increase in ”cognitive strain“, series of slides were prepared, each of which consisted of three slides as in Sequence II. In this third sequence, however, the first slide presented both intended dimension values in combination, the seconi slide presented one value of the concept and the last slide presented the other value of the concept. m of Sequence II; First Slide Seconi Slide last Slide Open Figures Denote Red Solid Figures Denote Black Concept: Bed -small. The total. mount of information presented was the sme for Sequence III as for Sequence II since the identical number of slides containing identical mounts of information were used. An increase in “cognitive strain" was produced by an increase in the interposing information for one value of the concept. In the ample , it is the value rod which is observed originally in the first slide but not confirmed until the last slide with the second inter- posing slide causing the interference. The mount of information that must be stored during the problem was the same (a total of seven dimension values) fa- Sequence III as for Sequence II. Sequence Iv - e "G tive Str ” -To provide -25-- the intermediate-high “strain“, series of slides were prepared which again consisted of three slides as in Sequences II and III. In the fourth sequence, however, the first slide presented one value of the concept, the second slide presented the other value of the concept an the last slide presented a combination of both values of the concept. mph of Sequence IV First Slide Second. Slide last Slide Open Figures Denote Red Solid Figures Denote Black Concept: Red ~ small The total mount of information presented was the same for Sequence IV as for Sequences II and III since the same mnber of slides was used. The same interposing information existed for Sequence IV as for Sequence III. There was no interference for one concept value (in the ample , the value red) and an interposing slide between the original. observation anl its confirmation for the other concept value. (In the exmple, the value small). -26- An increase in “cognitive strain" was produced by an increase in the mount of information that must be stored during the problem. In Sequences II and III, the first slide presents four values and the second slide duplicates one value but presents three new values for a total. of seven. In series of slides of Sequence IV, the first ani second slides each present four different dimension values for a total of eight. It was the increased number of dimension values to be stored in Sequence IV (eight) compared to Sequences II and III (seven) which increased the ”cognitive strain“ of Sequence IV. Sequence V - Most "egg-tin Stray! - To provide the most ”strain“ , series of slides were prepared which consisted of four slides each presenting one value of the intended concept. That value which occurred in the first slide was repeated in the third slide. The other value appeared in the second and last slides. .27- 13 of v First Slide Second Slide Third Slide Iest Slide Open Figures Denote Red Solid Figures Denote Black Grease-thatch Figure Denotes - Green Concept: Red - small There was an increase in the total amount of information presented by the addition of a fetn'th slide, fran ten dimension values observed in Sequences II, III and 1V to fourteen dimension values in Sequence V (in the example, the additional values are green, large, triangle and four). in increase of interposing information occurred in Sequence V for both concept values, as compared to Just one value for Sequences II, III and IV, have a slide interposed between the original observation of the value and its confirmation. In the ample , the value red is observed in the first slide but not confmd until the third slide. The value small is observed in the second slide and confirmed in the last slide. .23.. The mount of information that must be stored during the problem was increased with the addition of the fourth slide from a total of eight for Sequence IV to eleven for Sequence V. The criterion applied in the design of the slides was to develop sequences which would be of equal difficulty in all respects but that of ”cognitive strain" for the five types of sequences. For this reason, a master guide was developed of all combinations of two relevant dimensions out of the possible four dimensions. The relevant dimensions were then assigned values in rotation to prevent duplications. The remaining irrelevant dimensions were assigned values randanly except to avoid duplications. The master guide is shown as Appendix II. Using the master guide to select dimension values, each stimulus figure was drawn on tracing paper with India ink. The sizes of the figures were designed to be in proportion on the basis of the relativity of judment of sensation contained in Weber's law and were 3mm. for tim’, 6m. for small, 12mm. for mediumand 24m. for the large. Actual production provided sane shrinkage in size which did not reduce the distinguishableness of the four sizes. The appropriate Diazochrome sheet (Appendix VI) was processed according to the directions of the Technifax Corporation to produce stimulus figures in the colors green, red, black and orange. The colors were selected on the basis of an aura which created the most distinguishable differences 4.9- of the materials available. The processed Diazochrome was cut and mounted on the rear of 50 x 150 m. cardboard with a 25 x 100 m. window. This slide, when projected on the screen, created an instance in the experiment. A. detailed record of all dimension values of each slide in each sequence aid the order of presentation is in Appendix III. The procedure of systematidally assigning a combination of relevant dimensions ani randomizing the assignment of irrelevant values was an attempt to equalize difficulty inherent in am particular dimension value. However, it was possible to further control the effects of variations of dimension values for Sequences II, III and IV since they contained the same number of slides. These three sequences differed only in the position of the slide presenting both values of the concept in combination. Therefore, by rotating the order of presenting the slides in a sequence (as was done with the exmple used to describe the developnent of the five sequences), it was possible to change the type of sequence. By changing the type of sequence among three youps of subjects, any confounding difficulty of dimension values could be counter-balanced mong the three types of sequences. For ample , in Group A an example of Sequence II would have the slide containing both values of the concept occurring in the second slide. By presenting the slide containing both values of the concept slide first to Group B, this sequence became an ample of Sequence III. Fm'ther rotation in Group 0 would present the slide containing both values of the concept in the third slide, an example of Sequence IV. -30-- This possibility suggested the use of three groups of subjects in the experiment. The result of the rotation was that a particular sample of a sequence was used as an example of Sequences II, III and IV for each of three youps of subjects. If the particular combination of values were especially easy or difficult to identify, the effect would be distributed through the three different types of sequences. This added control was not feasible, of course, for Sequences I aid V since they contain a different number of slides. Another problem to be considered in the design of the experiment was the order of presentation of the sequences. The plan used was to randomize the order of sequences within a set containing one of each type of sequence. This procedure was followed for the first half of the total presentations. The second half of the presentations was the reverse of the first half to give a counter- balancing effect. Each ample frm the master guide was randanly assigned to the planned presentation. Sequence II was not added until after the master guide was originally developed so it does not follow completely the systematic pattern of assignment of values as used in the original development of the master guide. However, any effect frm the deviation was randomized by the rotation procedure. A final factor considered was the number of slides to be used. It was felt that fatigue would influence the results if the actual .31.. testing exceeded thirty minutes. Six examples of each type of sequence, one of each possible combination of dimensions, were used. The final testing time ran 22%minutes. Subjects The subjects were members of three Introductory Psycholog classes at Flint Community Junior College. In the analysis to follow, these classes are identified as Group A, B and C. All groups were tested in the Same room, using the same equipment and slides and it is felt that the testing conditions were the same for all subjects. However, since these conditions could have differed in sane unknown way, the group effect was studied as a factor in the statistical analysis of the experiment. 3.9m The projecting equipnent was a Vu—Graph overhead projector on a. podium placed nine feet from the wall-mounted, 72“ x 84" DaLite screen. The platen of the projector was covered with construction paper except for a window (30 x 105 m.) slightly larger than the slides (25 x 100 mm.). Guide lines to enable accurate determination of the figure's size were etched on the window. A stop on the mat accurately positioned each slide in the window. ocedure In conducting the experiment, the window drapes were closed and one-half of the overhead fluorescent lights were turned on. In .32.. this way the roan lighting was controlled for each group. This arrangement, while reducing the overall room light intensity to permit clear viewing of the projected figures, provided adequate lighting for the subjects to see as they wrote their responses. A response sheet (Appendix V), which identified the dimensions on! their values at the top, was distributed to each subject. On the response sheet were double lines for each ”rule", one for writing each value of the concept to be identified. The use of the response sheet was explained and demonstrated during an instruction period . When all subjects indicated they understood the task and how to use the response sheet, the experimenter installed the first slide, indicating that there were two (three or four) slides in that sequence. The assistant (*) turned on the projector for seven seconds and then turned it off for three . During the three seconds that the screen was dark, the assistant removed the slide that had been shown, the experimenter installed the next slide and indicated to the subjects the appropriate number of the next slide. The same procedure was repeated for the remaining slides in a sequence. After the last slide in a sequence was shown, the experimenter said ”write the rule“, the assistant removed the last slide am the experimenter installed the first slide of the next sequence. After the screen had been dark for thirteen seconds, the experimenter said (*) The assistant was an experienced laboratory assistant at the Flint College, University of Michigan. His task was to control the rate and pace of exposure by observing a stop watch. .II .33.. I'there are two (three or four) slides in this sequence, number one“. The assistant turned on the mojector five seconds later, ani the routine was repeated for all thirty sequences. The procedure was the same for each group except the order of presenting the slides was rotated so that a particular sequence which was an example of Sequence II for Group A. became Sequence III for Group B, and becme Sequence IV for Group Go The Otis Quick-Scoring Mental. Ability Test, Gamna Test: Form Em (30 minute), was administered to Group C inmediately after the experiment and during a later class session for Groups A and B. CHAPTER V MUSIS OF RESUIIS To evaluate the effect of the five types of sequences designed to achieve an increasing mount of "cognitive strain" in concept identification, an analysis of variance design was used. The general plan to test the mpothesis was to administer six examples of each of the five degees of "cognitive strain“ to all subjects. With each of the original set of eighty-four subjects responding under all five conditions, the effects of individual subject differences were balanced across the different, types of sequences. Repeated measurements at each level of "cognitive strain” resulted and the experimental design used in the analysis made provision for this (18, p. 337). In addition to the effects of the types of sequences, a second important main effect was evaluated . To obtain an adequate number of subjects, and to permit balancing exmples in Sequences II, III and IV, three groups of subjects were tested. The differences that might arise in the separate administration of the experiment to these three groups were controlled as far as it was possible to do so. But to estimate the effect of uncontrolled differences in the youps, the class membership of the subjects was included as a factor to be evaluated by the design. .35.. A third factor, intelligence, was evaluated as the third main effect in the analysis of variance. Scores fran an administration of Gama Test: Form Em of the Otis Quick-Scoring Mental Ability Test were used to partition each of the three g‘oups into three intelligence levels. The partitioning was made at the mean for all subjects plus and minus one-half stsniard deviation. The mean was 113.92 for all subjects with a stamiard deviation equal to 10.63. Partitioning produced a ”low" level with I.Q.'s equal to 108 or below, a ”mid” level with I.Q.'s ranging from 109 through 119 am a ”high" level with I.Q.'a 120 am above. This division resulted in an unequal number of subjects in the nine combinations of youp membership and I.Q. level. Proportionality was obtained by systematically casting out fifteen of the original eighty-four cases. Since it was desirable to maintain the original I.Q. distributions, the I.Q. scores were first ranked within each combination of youp and level. The 4th and 8th ranks were then removed from the combination Group C - High I.Q.; the 5th ran]: from Moup B - Mid I.Q.; the 3rd, 6th and 9th ranks fran Group 0 -Mid I.Q.; the 2nd and 6th ranks from Group A - Low I.Q.; and the lat, 3rd, 5th, 7th, 9th, 11th and 12th ranks from Group B - Low LQ. The revised groups were equal in size, twenty-three cases each, consisting of five subjects in each group at the intelligence-low lovel, nine subjects in each group in the intelligence-mid level, and nine subjects in each group in the intelligence-high level, for a total of sixty-nine subjects. -36- The resulting matrix provided a 5 x 3 x d analysis of variance design with sequences, groups and ability levels as the main treatment with repeated measurements on the sequences. Attaimnent of one-half the correct answer was not considered as correct identification of the concept on the response sheet. Therefore, the response sheets were scored' by indicating as incorrect all concepts (rules) that were founi one-half or entirely wrong. The total number of correct answers was recorded on data sheets (Appendix I). The means and standard deviation on the dependent variable, “correct” concept identification, for the analytic matrix are smmnarized in Table 1. .37.. men: 1 mm W 05' comprs mmmmn I AND STANDARD navmmns SEQIENCES GROUP A I II III IV V TOTAL SD. .74. 1 .16 .40 1.3 5 .80 1.60 Intelligence-Mid M 4.77 4.88 4.22 3.66 1.80 3.88 SD .78 .99 1.13 .81 .62 1.29 Intelligence-High M 5.77 5.00 4.77 4.33 3.22 4.62 SD .62 1.15 .78 1.56 1.54 1.44 TOTAL M 5.26 4.69 4.34 3.69 2.34 f. SD .84 1.10 .96 1.45 1.31 -- f @011? B I II III IV V TOTAL Intelligence-Ia! M 5.20 4.40 4.60 4.40 2.20 4.16 SD 7.48 1.20 1.01 1.01 .40 1.37 Intelligence-Mid M 5.1.1 4.88 4.33 4.44 2.77 4.31 SD 1.28 .99 .93 .82 1.13 1.36 Intelligence—High M 5.88 5.44 4.88 5.33 3.33 4.97 SD .30 .49 .30 1.23 1.94 1.05 mm M 5.43 5.00 4.60 4.78 2.87 | SD .97 .97 .82 1.21 1.1.3 ' . _ . . c n a .. . e a x . n n . n ._ v a . w _ u . a . t u a s .. a 1 1 v n .1 . _ . q n + v n a N H .— n t s a q r n _ . .. n ‘ u _ . . . . a o a . n I r s v o a a n v n r l V n a 1 h. -. .9 s A . w w .. n . a. v 1 __ . . . \ . . n n n n n A n O u s. I a 1 . , .33- men: 1 (Continued) mqusmms M I II III Iv v ram Intel-1189133940“ M 50w 4040 40m 20m low 3052 SD .48 .80 .63 1.41 1.03 1.50 Intelligence-Mid 8' 5.1.4 4.66 4.22 3.2.4 2.55 4.06 SD .68 1.05 .91 1.16 .95 1.38 Intelligence-High u 5.77 5.00 5.44 4.33 2.77 4.66 SD 041 066 o 081 1013 1.31 TOTAL M 5.16 4.74 4.65 3.47 2.43 SD .57 .89 1.00 1.24 1.05 SEQIEMS I II III N v rams M 5.43 4.81 4.53 3.98 2.55 SD .82 1.00 .94 1.37 1.31 SEQUENGES mmcmms 13731. I II III Iv v TOTAL Low M 5.33 4.20 4.13 3.00 1.80 3.69 SD .69 1.10 8.06 1.63 .78 1.51 mm M 5.11 4.81 4.26 3.85 2.40 4.09 SD .99 .94 1.00 1.10 .99 1.35 High M 5.81 5.15 5.03 4.06 3.11 4.75 SD 079 082 .69 1.43 1.51 1.30 rams @100? A GROUP B GROUP 0 GRAND M 4.07 4.54 4.18 4.26 SD 1.49 1.33 1.41 1.43 Assumptions One necessary assumption for use of the analysis of variance design is that homogeneity within cells exists. To test for homogeneity within cells, F max tests were made (18, p. 339). The computations indicated that the (a) between subjects in groups F max eqmd 4.02 where the required critical F max .95 with nine and eight degrees of freedan is equal to 11.10 and that the (b) within subjects in groups F max equaled 4.03 with the required critical F max .95 with nine and eight degrees of freedom equaling 5.15. Neither of the computed error terms exceeded its F ratio critical value at the .95 level and indicated that acceptance of the assumption of hunc- geneity within cells was warranted. The repeated measurement design used also assumes hmogeneity of covariance. A test for this assumption is given by Wiser (18, P. 369). The computation of a covariance matricesx 2 equaled 241.29; required critical value 27 2 .95 with thirty degees of freedan equaled 43 .80. The canputedx 2 exceeding the required critical value indicated that symetry in the covariance matrices did not exist. For this reason, the conservative tests of Greenhouse and Geisser (6) have been used which avoids assumptions about equal covariances in the pooled variance-covariance matrix. The use of repeated measurements design also assumes that the order of administration is randanized (16). The confouxfling effects .40.. that might result from position were minimized by several procedures. The order of the presentation was in sets of the five sequences with positions of the sequences within each set randomized. The second half of all the groups was presented in the reverse order of the first half. In this way, each sequence position was counter-balanced in its presentation. Six examples of each type of sequence were used. This permitted the use of one example of each of the possible combinations of relevant dimensions (canbinations of two relevant dimensions fran among four possible dimensions), and thus balanced possible effects of particular canbinations of dimensions in the tasks. A further control over effects of the use of particular dimension values in sequences was possible for Sequences II, III and IV since the tasks in these sequences were identical except for the order of the slides within each sequence. The order of presenting the slides for these sequences was rotated among the three groups of subjects to change the type of sequence. A sequence of slides which was an example of Sequence II for Group A became Sequence III for Group B by starting with the second slide. This same example became Sequence IV for Group 0 by starting with the third slide. By the rotation, possible variations in difficulty of dimension values was balanced for Sequences II, III ani IV. No other modification in the order of presenting the slides was made. It was felt that am other change would confound the order and reduce the value of the rotation control. .41... Since Sequences I and V required a different number of slides, smh a control was not feasible with resPect to these sequences. Therefore, the stringent .01 level was set for determining significance of main effects and interactions on the dependent variable. ksults The results of the analysis of the data are summarized in the following Analysis of Variance table (Table 2) . The conservative tests were used to determine the probability of obtaining the observed F's in those tests involving repeated measurement of the sequences. The critical values are shown for the two F ratios which turned out to be statistically significant. TABIE 2 SMART CF ANAHSIS 0F VARIANCE Source of Variation Between Subjects Groups Intelligence Groups 1: intelligence Subjects within 9301113 (Between error) Within Subjects Sequence Groups 1: sequences Intelligence 2: sequences Groups 1: intelligence 2: sequences Sequences x subjects Within Groups (Within error) SS 243.40 13.81 6101-8 1.96 166.45 550 .60 328 .27 16.13 10.72 184.82 (if 68 2 16 240 is 6.90 30.59 .49 2.77 2.01 1.34 .66 .77 F 2 .49 11.04 .18 106.58 2.61 1.74 .86 P F = 4.98 .99 (2,60) F = 7.08 (a) .99 (1,60) 0*) Conservative test using reduced d..f. (6) Si ic Factors . The difference in concept identification scores attributable to two of the main factors proved to be statistically significant at the .01 197910 The "cognitive strain" presentation sequences were indicated to be most significant and the hypothesis was jtdged to be supported by the experiment. The mean number of concepts correctly identified in each of the five sequences followed the predicted pattern of an inverse relationship between the amount of "cognitive strain” aid the effectiveness of concept identification. A graph in which the mean number of concepts identified was plotted against the five sequences illustrated the inverse relation (Table 3). TABIE 3 GRAPH OF MAN NUMBER OF CONCEPTS IDEM‘IFED Fm. SEQUEI‘CES Sequence 1 1:1 IQ IV V 5 . 50 Mean MM 5 .00 0f Concepts 4050 Identified 4.00 3 .50 3 .00 2.50 .44.. A further analysis using Duncan's Multiple Range Test (1..) showed statistically significant differences at the .01 level. between the concepts identified in all comparisons of types of sequences except between Sequences II and III (Intermediate-low and intermediate- median degrees of "cognitive strain“). TABIE 4 DUNCAN'S MUITIPIE BANG} TEST w EQUEMIES Mean of Concepts Identified by Sequence Shortest V IV III II I Significant flanges 2.55 3.98 4.53 4.81 5.1.3 at = .01 v 2.55 1.43 1.98 2.26 2.88 112 = .38 IV 30% 055 083 10195 RB = .49 II 4.81 0& R5 "" 042 Sequences Underscored Are Not Significant Differences in intelligence levels were found to be statistically significant at the .01 level. The mean of the mmber of concepts identified for the three levels of intellectual ability followed the positive relationship predicted between intelligence and concept identification. A graph of the mean number of concepts correctly identified plotted against the three levels of intelligence illustrated the relationship (Table 5). TABIE 5 GRAPH OF MEAN HOMER w CONCEPTS MMIFIED AT INJELLIEM EVBIS Intelligence level gap M 21:311— 5.00 Mean Utmber 4050 Of . Concepts 4.00 Identified £159 A further analysis using Kramer's modification for unequal 11's of the Duncan Multiple Range Tests (11) indicated that significant differences existed only between the high and mid, and high and low intelligence levels. TABIE 6 DUDICAN'S MUIIIPIE RAM TEST WITH KRAMER'S MODIFICATION Fm UREQUAL n's cu IM‘ELIICEICB IEVEIB Mean Number of Concepts Identified Shortest By Intelligence lavel Significant Ranges Low Mid High 3.69 4.09 4.75 0‘ = .01 Mid 4009 7066 RB = 6052 levels Underscored Are Not Significant A '46- The analysis suggested that the order of the relationship between levels of intellectual ability am concept identification was in the order predicted. However , this conclusion is statistically reliable for these data only for the comparison of the high-mid and high-law intelligence levels. Variance of the groups and the interaction effects of sequences, groups and intelligence levels did not prove to be statistically significant, indicating extraneous variables were controlled or randomized. GHAPI'ER VI SUMMARI AND DISCUSSION OF FINDIBBS A search for an explanation of variations in effectiveness of presentation sequences used as guidance in the concept identi- fication task initiated the present investigation. The amount of "cognitive strain“ induced by the sequences was postulated from past research as a possible explanatory principle. ”Cognitive strain" in an identification task was developed in five ascending degrees by manipulating three conditions : (a) total amount of information presented for observation, (b) amount of interposing information an! (o) amount of information to be stored during the solution of a problem. Three groups of Introductory Psycholog students were used as subjects in the study. Each subject attempted six examples of each of the five degrees of ”cognitive strain”. Identi- fications were scored for the number correctly made by each subject. An analysis of variance of the main effects of youp membership, intelligence levels, and presentation sequences was made with repeated measurements on the sequences. The results showed a decreasing number of concepts correctly identified in each sequence when the latter were ordered for increasing ”cognitive strain" . Differences were statistically significant for the comparison of adjacent sequences in three of the possible four canparisons. 4.7- .43.. The data supported the hypothesis of an inverse relationship existing between amount of "cognitive strain" and effectiveness in concept identification. The hypothesis that a positive relationship between intelligence and concept identification would be found also appeared 3 statistically warranted. No significant interactions between the main effects were discerned. Interge‘tgtion of Figs Intelligence 11er to be a significant factor with a positive relationship to concepts attained. This is to be expected on the basis that an I.Q. score is reflecting the ability of the subject to deal with concepts and symbols and indicates validity of the concept ' task. It was found that the significant differences were between only the high and low, and high and mid levels, of 1.0. scores. The factor which may have prevented greater differences fran developing between the low and mid levels is a selective intelligence factor of the subjects who as college stxxlents are intellectually a select group. A ”basement effect” resulted in a skewed distribution as indicated by the number of cases in the preportional intelligence levels. The result was that the low intelligence level contained a maller number of cases than the mid and high levels. The actual range of the center level was only ten I.Q. points and due to the overlapping of levels that would occur from variations in testing, combined with the smaller number of cases, no statistically significant differences between mid and low levels developed. ~49- Non-significant findings for group effects is interpreted to indicate that differences that may have endsted between the groups were not goat enough to influence the results. Non-significance of the interaction effects is taken to mean that all other variables were adequately randomized or controlled. The three conditions which were used to increase "cognitive strain” occurred in combinations except in the comparison of Sequence II with Sequence III. The condition that distinguished Sequence II fran Sequence III was based on the assumption that inter- posing information would increase cognitive activity. The assumption developed from the interpretation of the conclusions of Bruner, et al, and the evidence presented by Hunt. The evidence found in the present study conflicting with that found by Hunt reflects the difficulty that exists in measuring and manipulating "cognitive strain" . It is possible that the amount of interposing information in this comparison was not great enough to cause a noticeable increase in cognitive activity. It would be possible in an experiment of four slide problems, in which each slide contained a single correct dimension value, to arrange the order of the slides to obtain different amounts of inter- posing information. Such an investigation could confirm the work of Hunt for the type of concept task used in the present investigation. In any case, further investigation of the contradictory evidence may be one of the most fruitful areas to achieve a clearer understanding -50- of the relationship between “cognitive strain" and concept identi- fic attion. The important contribution of this study was the defining and testing of "cognitive strain" and the inverse relationship to concept identification. In so doing, a basis was verified for estimating aid manipulating “cognitive strain” on the assumptions of the subject 's encoding which was suggested but not tested by Glanzer (5). The value of the evidence lies in its use in analyzing presentations to achieve the meanmm concept identification. Progrmed learning is an exmple of where the idea of ”cognitive strain" may be applied to a concept identification task. A smple of programed material is as follows: "1. By behavior the psychologist means those acts that can be observed by another person or by an experimenter's instruments. Whenwe observe achild crying,we are behavior observing . 2. If we measure breathing rate by use of observing (or instruments, we are - behavior. measuring) 3. When we give a test to a person aid then made that test, we are observing behavior ." (16) It can be observed in this sample that examples are used in short direct statements with a minimum mount of “cognitive strain" as in Sequence I of the experiment. There is a minimum mount of interposing information since the response follows closely the introduction of the concept in each frme. Another condition -51- contributing to low "cognitive strain" is the low mount of storage information that must be stored before confirmation due to the mall steps, similarity of ideas and context. With low "cognitive strain", concept identification is maximized and learning proceeds rapidly. Is there a disadvantage to low "cognitive strain"? Frequently learners demonstrate rapid effective learning from progrmed material but often they don't like it. The low "cognitive strain" of prog‘ming results in a balanced situation with everything running smoothly so that a state of discontent develops. It may be conjectured that a teacher, in making concept attainment most effective , may also create discontentment and lessen motivation. Finally, in the present study three presentation conditions were found to vary "cognitive strain" while in the studies by Bruner, et a1, it was found that strategies could vary "cognitive strain". 0n the basis of the evidence and procedures used to manipulate ”cognitive strain" in the present investigation, it is now possible and certainly desirable to conduct an investigation with variations in both presentation conditions and strategies as studied by Bruner, et al, to evaluate the effect on concept identification of the inter— action of these variables which have been evaluated independently. ~52- APENDIX I DATA SW8 Correct Identifications of Sequence Code Number Subject I.Q. III IV V 105 II Group A (1) 656 23/... .45 32 46 56 121 lll 107 113 135 112 ll? 92 109 103 veemnunMsn 129 126 109 102 85 126 121 1+ 5 6 ( ) Indicates a case which was cast out in the proportionalizing of the intelligence levels of gasps. .53.. APPENDIX I (Continued) Correct Identifications of Sequence Code Number Subject I.Q. V III IV II Group B 121 27 (28) 29 (30) 106 megmmm ‘31 (32) 2433 4665 5546 36/05 146/06 33 (34) 35 36 37 38 55 56 6/». 46 5 5 123 127 ll? 132 52 53 (54) (55) so 106 98 -54- AHENDJI I (continued) Correct Identifications of Sequence Code Number Subject IoQ. V III IV II Group 0 57 58 59 (61) 135 63 64 65 66 67 68 69 127 117 135 (70) ('71) 72 115 75 103 (80) 120 81 , (83) 84 4% APPENDIX II MASTER GUIDE PCB. DIMENSION VAIIJES S V Mmmmm T1117 Small lag Ikflm aha Tflmwhrmws may 6mm me an an: A B cam: Mmm Mme Mme Rm Tm Qmmflp Imucwehmws GwfidJfimmimmfieWBwmwtfimmhm. ifikflenmhmmdMMamm F hSMh TMMSH® %mfl$ fiflLflfla &£M&a awmawa 22 3 chwmn uwummm m “Maw & maafl 221323 BCDCDD Mmummm 123456 IH aeuuuu «mu am mamumu munmmm wawmum wwwmmm awawug unammw ummamm ammawm mummmm m nmmw 789mnu aemwam manage ‘ 3 MMDMNM um Maw flafim 31.23 0.0 ob Mame umuu 32 a1 c3 d1 D1 a1 b1 31 «wean eewemm .mwfianu 42 MMMMDG Buwmmm -56- APENDDI II (Continued v musm Secmomsum W W 19 B1a203d2 A3b301d1 B1a102d4 ”1320463 20 A2b3c1d2 0384b1d4 A2b402d1 G382b3d3 21 D2a4b2c4 A1b1c1d1 D2a3b303 A1b4c2<13 22 338202611 C1a3b4d2 83a10363 019.4‘b2d2 23 D3 31 b1 61 B4a3c3d4 D3 a.2b2 c4 84340262 24 043413362 D4a2b1o1 0433b463 D4a1b203 no) 25 D2 a1 b1 c1 02 D2 32 b2 02 a4b4d1 26 D433 13‘] 64 A2D4. b3 03 A2132 325.3 27 D3 33 b3 61.. 32 D3 82 (:1 32 M63 (11 28 Mb201d2 M04b4d4 04a3b3d3 29 33626462 MB3C1d1 Ali-13403“ 30 0333b2d1 BAGBaAdZ B432¢2d4 (*) Sequence II was added after the first trial run and was an addition to the guide. APRINDII III DMNSIOIB AND (HER OF SEQUENCE HESEMATION Fourb Slide Second Slide Third Slide First Slide *eouenbeg .1er 8683 TOLL. TGSA TRTl TOLA RBSl GGLl TGMZ 00142 ROTA. ROL2 19 17 25 11 3 3 SRTl 3081 110141 R0131 86141 T GT 3 TRLI. RBSB TRSl RGLZ GRM3 R3133 T 6M3 SGM3 GGT 1 TRT 4 GBMA. GRSA. RGM3 RGLl 3081.. ROLB TRTZ SBSB TGMZ ~57- =393=49 2,A.=3ForGroqu. A. Due to rotation of presentation in groups, 2 3 :35 lml alt- v3: «‘5‘? ”“1”. “35 u 353 “1 I'lg'q misty; W 2"38 :5 00.43 » :13 «Béam 5335? E: is} s: l'l ‘APEENDIX III (Continued) F Slide Second Slide T at Slide fixunfime eats antes Ahrmnme ezrs JDIoo .3. Gwenbes mm T BSB 1101.1 0 0M3 R082 TRSA. SGT2 2 21 1 5 13 TRL3 GBSZ RBM2 RGL3 8383 14 15 16 17 TBLA SBLl SBT2 14 2 CGL4 ROMA. RBTl CRTA. SBM2 GBM2 SRT 1 T BMl OGS 1 T GT 1 GGL2 GBSB 0 01.1 R084 TRHZ RBM2 RGT 2 29 18 .3 TBL2 GBT2 RRSZ 19 20 SOM3 0BL3 TRM4. RGT2 21522 CRT2 223 30 23 0 GT 2 0 0M1 TRT 2 SRTZ 244.12 25 RGT3 00M2 GBMI. SBSl GOTL SRT4 26 27 28 29 $082 -53- SR L3 TRMl SBS3 0683 30328 —59- APPENDII IV DIRECTIONS TO SUBJECTS This is a task in remembering. You will see a sequence of two, three or four slides (show example slides) that vary as shown at the top of the reaponse sheet. Notice: The four sizes - large, medium, small and tiny. The narrow horizontal lines on the screen are the height of the small shapes. Shapes that are not as tall as these lines are tiny. The wide horizontal lines are the height of medium shapes. Ierger shapes are large. The four colors - orange, green, black, red. The four shapes - circle, triangle, cross, square. The four numbers - one, two, three, four. After viewing a sequence, you are asked to write a rule for that sequence -- two values that occur more than once. (Show example). Some slides will show the complete rule, two values. Some will show half the rule, one value. All slides will show at least one-half the rule. Do not make notes describing each slide; rather try to remember. You need to remember all the slides in a sequence to get the best rule. However, if you are not sure guess. There will be two, three or four slides in a sequence. I will tell you at the beginning of the sequence how many slides will appear in that sequence. ALPIENDIX IV (Continued) Iet's look at sane examples and I will explain how to use the answer sheet. (Show examples). Since the rule is and , write the rule on the response sheet (demonstrate *) . If the answer is size or color, write the first two letters of the word; if shape or number, write the symbol (demonstrate). (Repeat with second example and demonstrate answers) . Now let's try some samples. This time you write the rule in the sample spaces with two letters for a size or a color and the symbol, shape or number when appropriate . (Show samples and review after each, pointing out the values and correct method to record the intended rule). (Make the statement). I wish to avoid causing any embarrassment. However, to insure the data is accurate, will you indicate at the bottom of the page if you experienced an eye difficulty due to color blindness. (*) A duplicate of the reSponse sheet on acetate was projected on the viewing screen. The response for the example was written on the acetate to demonstrate the use of the response sheet . -61- APENDJI V Name RESPONSE sneer Isms SIZE - large Edim Stall Tm cone -m seen mack ma Sim—O A + I mum - l 2 3 4 Sample 1 Sample 2 Sample 3 Sample 4 ——-—~ Indicate the rule for each sequence - the two values which occur more than once. Immi :mm11___ mmun::: 1111132: Rulelz: 12111322: IMb3::: Ruen___ mmua::: Rulelt: Ruleu: Ru1e24: RMs5::: IMh15::: IMb25::: ame6::: mmxw::: 1Mh26::: 1111197: Rulel7_____ Hui-627:...— IMb8::: mmxm::: mmnw::: Rule9: RuIe19: 111214929: RfleEC:: IMb20::: 1mm3o___ APPENDIX VI EQUIHENT AND MATERIAL l. Projecting Equipment Transpaque Junior Model 6000 Projection Optics Company, Inc. Bast (range, New Jersey 2. Material used to produce slides: 99.195. 9.9112 1. Diazochrome Green KGN 2. " Red m0 3 . " Black EX 4. " mange KCR Technifax Corporation 195 Applet on Street Holyoke , Massachusetts 3. Otis Quick-Scoring Mental Ability Tests: New Edition, Gamma Test: FormEm (30 minute); Harcourt, Brace and World, Inc., New York 4. Screen A wall-mounted 72“ x 84" Matte Model ”B” De Lite Corporation Chicago, Illinois .63- BIBLIOGRAPHY (1) Archer, E. J.; Bourne, L. 3.; Brown, 12. F. - Concept Identification As A; Function 0f Irrelevant Information gg Instruction - J. Exp. Pay. 1955, Vol. 49, No. 3, p. 153 (2) Bruner, J. 8.; Goodnow, E. J.; Austin, G. A. -g Stgz or W - New York; Viley, 1956 (3) Cattell, R. B. - Persogutz - McCraw-Hill Book Canpamr, Inc. New York, 1950 (4) Edwards, A. L. - riment Des In hol c e - Holt, Rinehart and winston, New York, 1 (5) Glanzer, M.; Huttenlocher, J.; Clark, U. H. - W ions In Sol Conce Problems - August, 1962 - In Press - Psychological Monographs (6) Greenhouse, S. w.; Geisser, S. - 01 Methods In The Mia Q Profile Data - Psychometrika, 1959, Vol. 24, No. 2 - June, 1959, p. 95 - 111 (7) Hanawalt, s. M. - flole And ngt Methods In Trial And Error Iearnigg: m gage Iearnigg - J. Exp. Pay. 17, 691 - 708, 1931. (8) Hovland, C. I. - Communication Maia 0f Concept legging - Psychological Review, Vol. 59, 1952, p. 4.61 (9) Rowland, 0. 11.; Weiss, U. - raggesion 0f Infmtion Comm Concefis Through Positive And Negfiive Instgpgg - J. Exp. Psychology, 1953, 459 P0 175 " 182 (10) Hunt, E. B. - Memgz Effects In Concefi lam - J. Exp. PSYChOIOQ, 1961, V01. , NO. , p. 598 "' $4 (11) Kramer, C. Y. - Efiension 01‘ Multiple Range Tests To Farm Means With Unegfl Numbers 0f Replicgtiogg - Biometrics, 19 , Vol. 12, (12) Page, E. B. - Ordered Mothesis For Multiple Tregments: A Signfiicgg Test For Linear gag - Journal of American Statistical Association, March, 1963, p. 216 (13) Pechstein, L. A. - Eole vs, Pg; Method In Motor may - Pay. Monoyaph #99 , 1917 (14) (15) (16) (17) (18) -6-’+- BIBLIOGRAPHY (Continued) Smoke, F. L. - An Ob'ective St 0f Conce Formation - Psychological Monographs, 1932, B No. 1. (Whole No. 191) Teevan, R. 0.; Jandron, E. L. - Student Guide For fliplggg's Introduction To Pflholgg - Harcourt, Brace & World, Inc. New York, 1962 Thorndike, R. L.; Hagen, E. - Megurement And Evaluation In ngholgg And Education - Second Edition, John Wiley and Sons, Inc., New York, 19 1 Underwood, B. J. - mimentg Pgflholggy - Appleton-Centim- Crofts, New York, 1949 Miner, B. J. - Stgisticgl= Principles In Emrimentgl= Desig - McCaaw-Hill Book Company, Inc. , New York, 1962 “711i Ilium