Developmental changes in predicting one's own span of short-term memory

Developmental changes in the accuracy of predicting one's own recall were studied, using preschool, third grade, and college subjects in Experiment 1 and third grade and college subjects in Experiment 2. Experiment 1 showed that prediction accuracy increased from the preschool to the college years, subjects were not influenced by a potential “expectancy” bias in the procedure, and only third grade subjects were influenced by the presence of norms about peer performance. Experiment 2 showed that third graders and college subjects lower their predictions in the face of “false” norm information, with college subjects being the only group to under predict actual recall in both experiments. Thus, although adults are significantly more accurate than elementary shool children in estimating short-term recall, their susceptibility to norm information suggests that even they have uncertainty about their exact capabilities.     

Effects of warm and neutral models on the attention of observational learners

The study was conducted to examine observers' attention to adults following warm and neutral interactions with them. Forty-two preschool and 36 third grade girls interacted with a pair of female models in one of three treatment conditions in which models were, respectively, warm and neutral, neutral and neutral, or warm and warm. Subiects then witnessed the models play a picture-preference game and were asked to recall the models' responses. Analyses of the children's overt attention to the models' responses revealed a greater attention to a warm model when in the presence of both a warm and neutral model and less distraction by nonsocial stimuli when at least one warm model was present. A significant positive correlation was obtained between attention to and recall of the models' responses.     

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.     

Environmental determinants of altruism: The effects of stimulus overload and perceived control on helping

In an experiment designed to measure the effects of stimulus overload on altruism, 60 female subjects were randomly assigned to three stimulus conditions of 20 subjects each: (1) overload, (2) overload with perceived control, and (3) no overload. Subjects performed simultaneous proofreading and number attention tasks while at the same time listening to distracting or nondistracting background sound, and one group believed they could have the sound turned off if they desired. Following task performance, all subjects received a request for a favor from an ostensibly unrelated confederate. Although all subjects performed the tasks about equally well regardless of stimulus condition, altruism increased significantly across the three conditions. Results were discussed in terms of stimulus overload associated with the urban environment.     

The response ratio hypothesis for magnitude estimation

Assume that each presentation of a signal produces two independent random variable representations and that the ratio of responses on successive trials of a magnitude estimation experiment are proportional to the ratio of a representation from the present trial, which representation is then lost, to the remaining one from the previous trial. The mean response to a particular signal depends on the mean of the representation used, but in general exhibits drift over trials and sequential effects due to the preceeding trial; the mean response ratio does not exhibit drift, but it has a simple form only when there are no sequential effects; however, a modified mean ratio function has a simple form. A model suggested by D. V. Cross is a special case of this one. Simple timing and counting models for the representations fail to exhibit sequential effects, contrary to considerable data. However, data of the authors have suggested a version of the timing model in which the sample size of the representation varies by an order of magnitude depending on how close the signal is to the preceding one; this hypothesis accounts for the observed sequential effects and other aspects of the data.     

The perception of consistency in attitudes

A study was conducted to test the hypothesis that when people change their attitudes they reduce the dissonance associated with the inconsistency of their new and previous positions by distorting their recall of their initial stand to make it consistent with their new attitude. Small groups of high school students discussed bussing, one of 30 pretested issues. An experimental confederate participated in each session with the task of effecting attitude change. After the discussion, the subjects' new attitudes were assessed and they were asked to duplicate their pretest scores. The results confirmed the hypothesis. Subjects distorted their recall of their initial stand on bussing so as to make it consistent with their new attitude. Such distortion allows persons to feel that their new position is the one they have always held. The subjects made such recall errors only on the bussing issue. Control subjects did not distort their original bussing attitudes.     

Differential reinforcement of interresponse times with controlled probability of reinforcement per response

Pigeons were presented food after interresponse times (IRTs) longer or shorter than a fixed percentage of their most recent IRTs. This procedure controlled probability of reinforcement per response while still allowing different classes of IRTs to be reinforced differentially. Support was found for IRT-reinforcement theory in that response rates were determined by the degree and direction of differential reinforcement of IRTs, but were relatively independent of probability of reinforcement per response and of the length of the control system's IRT memory. Stimulus control of these differential response rates was also demonstrated.     

Covariation and temporal contiguity as principles of causal inference in young children

Four- to seven-year-old children observed a simple physical effect which could be attributed to either a consistent but noncontiguous covariate or a contiguous but inconsistent covariate. When there was a physical rationale for the temporal delay between covariate and effect, children attributed the effect to the consistent but noncontiguous covariate. In the absence of such a rationale, they attributed the effect to the contiguous but inconsistent covariate. It was concluded that neither consistent covariation nor strict temporal contiguity were essential aspects of causal inference for these children.