Hobbits and orcs: Acquisition of a sequential concept

Subjects solved the hobbits-orcs problem repeatedly until they made no errors on two successive solutions. Groups varied in the kind of feedback given after errors. Further support was obtained for Thomas' (this journal) conclusion that subjects organize the sequence of moves in small subsequences, rather than individual moves. Differences between feedback groups suggested that the organization is oriented forward in the problem, and this contrasts with GPS' retroactive organization of this problem. Comparison between feedback groups also leads to the conclusion that subjects learned from positive information indicating which response is correct, rather than by a process of eliminating errors or sampling new strategies after errors. Analysis of acquisition data agreed with the hypothesis of all-or-none learning at individual states, except for one state where the additional complexity was related to an ambiguity about backward moves. The general pattern of results was invariant over a change in the characters of the problem (men and elves) designed to produce a reversal of relationship between the characters concerning who was prevented from outnumbering whom.     

Serial learning: Identification of subjective subsequences

Learning of fixed arbitrary sequences proceeds by idiosyncratic subsequencing and assembly of the resulting subsequences. An error item that just precedes a subjective subsequence is a closely constrained member of that subsequence. Identification and characterization of subjective subsequences were accomplished by analyses of forward serial learning, free recall, and backward serial learning. We conclude that ordinary serial learning cannot be represented by traditional continuous-process theories, but instead must be treated by an organizational model.     

Interpersonal needs and functional area of management

This study examines a sample of first-semester MBA students to determine the relationship between their interpersonal needs and their preferences for a functional area of management. The students were categorized according to their preference for one of the following eight functional areas: accounting, systems analysis, finance, small business management, engineering, marketing, manufacturing management, and personnel management. Interpersonal needs were measured by the Fundamental Interpersonal Relations Orientation (FIRO-B) instrument developed by W. C. Schutz. Significant differences in interpersonal needs were found among students preferring different functional specialities. Implications of the results are discussed in terms of occupational choice processes.     

Interpersonal comparison versus persuasive argumentation: A more direct test of alternative explanations for group-induced shifts in individual choice

One class of theories explains group induced shifts in individual choice in terms of interpersonal comparison process. By comparing himself with others a member finds out that his position is uncomfortably discrepant, e.g., he is overly “cautious” or overly “risky”. Knowledge of this discrepancy presumably is necessary and sufficient to induce him to change his initial choice. Another class of theories holds that merely knowing one is different from others is unimportant. Shifts in choice occur because during discussion a member is exposed to persuasive arguments which prior to discussion were not available to him. Thus, if in a factorial design one independently varied (a) the number of others' choices available for comparison and (b) the number of arguments others presented in support of these choices, interpersonal comparison theories would predict the magnitude of the shift to be a function of (a) and not of (b), while theories of persuasive argumentation would predict the opposite. When such an experiment was performed the only reliable main effects were based on the number of arguments, (b), as predicted by persuasive arguments. In no instance did effects involving (a) approach significance.     

A signal detection framework for the evaluation of probabilistic forecasts

In this paper I formulate an approach for evaluating probabilistic forecasts in terms of signal detection theory. Signal detection theory provides a powerful perspective for this type of problem, and a rich empirical background including methodological tools as well as an extensive body of research in many domains. I propose procedures which emphasize the maximization of expected utility for the decision maker who uses the forecasts. Further, I suggest approaches to obtaining indices of calibration and resolution within this framework. I also present arguments that the proposed indices will exhibit the same basic properties as do decompositions of Brier's (1950, Monthly Weather Review, 78, 1–3) mean probability score. However, the properties may be reflected in different ways, and hence, the present methods may lead to different conclusions about forecasting ability. Finally, I argue that the use of an expected utility loss function makes this approach more appropriate for practical applications as well as for theoretical research than other procedures with more arbitrary loss functions.     

Exposure effects and associative learning

The contributions of initial stimulus affect and of associative learning to the effects of repeated stimulus exposures were examined in two experiments. Stimuli that were initially positive and stimuli that were initially negative were presented for different number of times, and subjects rated these stimuli afterward on a number of affective dimensions. In all cases, except when negative affect was associatively paired with every stimulus exposure, affective responses became increasingly more positive with increasing exposures. The results were taken to indicate that the exposure effect can overcome an initially negative stimulus affect when the conditions of the mere exposure hypothesis are satisfied. Initial stimulus affect and associative learning of affect were shown to be independent factors, the first influencing the intercept of the exposure function, the second its slope.     

Perceptual supports for one-to-one correspondence in the conservation of number

This study compared provoked and spontaneous one-to-one correspondence along with two tasks having more perceptual support for correspondence. These four levels of correspondence appeared in a conservation of number condition and two conservation-related conditions (a partially static array or a static array). There were two sets of stimuli (toy animals or corks) in each condition. In opposition to Piaget's predictions, the four levels of correspondence did not differ in difficulty for kindergarteners. There was a strong order effect (p<.001) in the direction of increasing conservation over the eight trials. There was some evidence that the standard conservation condition was easier than the other two conditions. Implications for Piaget's theory are discussed.     

Testing two classes of theories about group induced shifts in individual choice

One class of theories explains group induced shifts in individual choice in terms of interpersonal comparison process. By comparing himself with others a member finds out that his position is uncomfortably discrepant, e.g., he is overly cautious or overly risky. Knowledge of this discrepancy presumably is necessary and sufficient to induce him to change his initial choice. Another class of theories holds that merely knowing one is different from others is unimportant. Shifts in choice occur because during discussion a member is exposed to persuasive arguments which prior to discussion were not available to him. Two experiments were conducted, the results of which give considerable support to persuasive-argument theories and none to those based on interpersonal comparison: When a member did not know whether others were arguing for their own position or were forced to support a position contrary to the one they had originally chosen, and the former in fact was the case, typical shifts in choice were obtained. However, if a member had to argue for a position contrary to the one he had initially chosen (and thus he would not be able to muster highly persuasive arguments) typical shifts did not occur, even though another's initial choice could be accurately inferred.     

The confluence model: Parameter estimation for six divergent data sets on family factors and intelligence

Theoretical predictions, based on the confluence model, were made for data from six national surveys of intellectual performance. All six surveys relate intellectual performance scores to family configuration variables. Widely divergent patterns of relationships between the major family factors, such as birth order and family size, and intellectual performance scores characterize the six data sets. Nevertheless, the confluence model was capable of accurate prediction in all cases when all three parameters were estimated. Little accuracy was lost using only two parameters. Variations in the estimated parameter values that reflected the variations in patterns of effects could be meaningfully interpreted for their psychological significance.     

A strong test of exposure effects

A strong test of exposure effects was made by eliminating confounding demand characteristics through the use of a between-subject design. Each subject viewed novel stimuli at a single frequency level, and then rated them on several affective scales. Frequency of stimulus exposure was systematically varied across subjects. Stimuli were rated more positively with increasing exposure, despite the fact that subjects were unaware of any differences in exposure frequencies, and clearly unable to identify the experimental hypothesis. An awareness of the relationship between repeated exposure and affect was thus shown to be an unnecessary condition for the occurrence of exposure effects.     

An axiomatization of the ratio/difference representation

If ≥_r and ≥_d are two quaternary relations on an arbitrary set A, a ratio/difference representation for ≥_r and ≥_d is defined to be a function f that represents ≥_r as an ordering of numerical ratios and ≥_d as an ordering of numerical differences. Krantz, Luce, Suppes and Tversky (1971, Foundations of Measurement. New York, Academic Press) proposed an axiomatization of the ratio/difference representation, but their axiomatization contains an error. After describing a counterexample to their axiomatization, Theorem 1 of the present article shows that it actually implies a weaker result: if ≥_r and ≥_d are two quaternary retations satisfying the axiomatization proposed by Krantz et al. (1971), and if ≥_r′ and ≥_d′ are the relations that are inverse to ≥_r and ≥_d, respectively, then either there exists a ratio/difference representation for ≥_r and ≥_d, or there exists a ratio/difference representation for ≥_r′ and ≥_d′, but not both. Theorem 2 identifies a new condition which, when added to the axioms of Krantz et al. (1971), yields the existence of a ratio/difference representation for relations ≥_r and ≥_d.     

Storage and later recognition of exemplars of concepts

This paper concerns the problem of abstraction: whether when we encounter several exemplars of a concept, we retain only the abstracted concept, only the exemplars, or both. Although many studies concur that both are stored, a recent article argued strongly that only the abstracted concept is stored. The present study, aimed at replication of this recent finding, follows the earlier procedural details but adds appropriate controls and uses simpler material. A set of 24 exemplars of four concepts, in the form of four-tuples of letters and numbers, was presented to Ss who, after presentation, rated a larger set of exemplars for recognition. One group of Ss experienced the conceptual exemplars; control group Ss experienced items that were similar in composition but not exemplars of a concept. Two major results appeared: Unlike the study on which this was based, all Ss were able to distinguish those items that were originally experienced from those that were not. And, the more completely an exemplar fit the concept (the longer the item), the more confident the S was that it had been presented. In contrast, in the control condition, the longer the item, the more confident the S was that it had not been presented earlier. Two models are described to account for these results. One is based on the S's initial storage of the exemplars in a concept-plus-correction format; the other is based on a procedure whereby the S can make recognition judgments without having previously abstracted and retained the concepts.     

Sociodramatic play: Social class effects in integrated preschool classrooms

In previous studies, social class differences in children's sociodramatic play were studied in socially homogeneous, segregated schools. However, social class differences in play behavior were attributed to the abilities or interests of the children rather than to the situation in which they were observed. In the present study, sociodramatic play was observed in middle and lower class children attending the same preschool classrooms. In accord with previous studies, middle class children engaged in a higher level of play than did lower class children. Analyses of individual play components indicated that although middle class children verbalized more frequently, the quality of the language used by the two groups did not differ. Age differences were also significant. With age, play roles became more socially coordinated, the duration of play episodes increased and language became more complex. But social class groups did not differ on these measures. The implications of these results for the developmental lag hypothesis, other explanations of social class differences and classroom strategies are discussed.     

Persuasive argumentation and social comparison as determinants of attitude polarization

Several of our studies indicate that persuasive-arguments theory by itself is an adequate explanation of polarization. Sanders and Baron (Journal of Experimental Social Psychology 1977, 13, 303–314) criticize this research. More generally, they contend that both argumentation and comparison are involved, “with persuasive arguments facilitating the shifts motivated by social comparison.” We feel that their critique is unconvincing. Relevant portions of the standard literature are reviewed to demonstrate that social comparison is neither a necessary nor sufficient condition for polarization. Finally, we speculate about how persuasive-arguments theory could be extended to argument-poor settings (e.g., Asch's line comparison situation).     

The effect of mere presence on social facilitation: An unobtrusive test

An unobstrusive experimental manipulation was used to test the hypothesis that the mere presence of others can influence an individual's performance. A task was employed for which there were no clear performance criteria, and which was very unlikely to engender evaluation aprehension. Performance times on this task (dressing and undressing in familiar and unfamiliar clothing) were compared for subjects working alone, in the presence of a passive inattentive person, and in the presence of an attentive spectator. In contrast with the Alone condition, both social conditions (Audience and Incidental Audience) enhanced performance on the well-learned aspects of the task (dressing and undressing with one's own clothing) and hindered performance on the more complex aspects (working with unfamiliar clothing). It is concluded that the mere presence of others is a sufficient condition for social facilitation and social interference effects.