The influence of positive and negative reinforcement on selective attention in the rat

In Experiments 1 and 2 rats were trained under two multiple schedules of reinforcement. In one, bar pressing during a tone-light compound stimulus was reinforced under a variable-interval food reinforcement schedule. In the other multiple schedule, bar pressing avoided grid shock on a free-operant schedule. In both multiple schedules, a discrimination was maintained by an extinction schedule that was operative during the absence of the tone-light compound. In Experiments 1 and 2 the intensity of the tone-light compound was manipulated over three levels. Subsequent extinction tests revealed that light was attended to, almost exclusively of the tone, when food reinforcement had maintained bar pressing. On the other hand, the tone gained considerable attentional control under the shock avoidance schedule. This stimulus-reinforcer interaction was maintained for all three levels of the compound intensity. In Experiment 3 it was investigated whether this interaction was associative by presenting shock during the absence of the tone-light compound when food reinforcement maintained responding, and food during the absence of the compound when shock avoidance maintained responding. Since both food and shock were presented during a single session for both schedules, nonassociative effects of the reinforcing stimuli were equivalent across the schedules. Nevertheless, the stimulus-reinforcer interaction was maintained, indicating that the interaction was an associative effect.     

The effect of the temporal locus of the introtact probe on the hypothesis-testing strategies of kindergarten children

The hypothesis-testing behavior of kindergarten children in discrimination learning was studied in a factorial design with two temporal placements of introtact probes (pretrial and posttrial) and two types of pretraining (unidimensional and multidimensional). Pretrial probes consisting of a request for the child's current hypothesis were administered in a conventional manner at the beginning of each trial with the stimuli in view and prior to the choice response. Posttrial probes were administered also with the stimuli in view, but after the choice response had occurred and feedback information had been provided. Learning-to-learn experience in solving three pretraining problems was given either with unidimensional simultaneous problems or with more complex multidimensional problems like the criterion tasks. The results indicated that posttrial probes produced superior local consistency, win-stay, and lose-shift probabilities, relative to pretrial probes, for both types of pretraining. Posttrial probes, however, facilitated learning and the testing of valid hypotheses only for multidimensional pretraining. These results are consistent with the hypothesis that posttrial probes constrain the child to be locally consistent and therefore improve short-term efficiency in hypothesis testing under both pretraining conditions. However, posttrial probes produce an improvement in long-term efficiency, and therefore in learning, only when other components of a successful strategy are acquired as in multidimensional pretraining.     

An application of a biased version of the Bradley-Terry-Luce model to professional basketball results

Some extensions of the Bradley-Terry-Luce model for paired comparisons are presented and used to assess the existence of a home court advantage for professional basketball teams. It is shown how maximum likelihood estimates for these models can be obtained from a simple iterative scaling algorithm. Won-loss records for the regular season are used to make predictions for playoff series. The models are extended to include possible differences among divisions. These models can be applied in many other situations to incorporate group effects and order effects into analysis of paired comparisons.     

Factors affecting hypothesis testing in kindergarten children

In a previous experiment, the authors demonstrated that kindergarten and first-grade children can be trained to test hypotheses sequentially within the context of a discrimination learning task. The present experiment is concerned with delineating various aspects of the pretraining that contribute to the improved hypothesis-testing strategies of kindergarten children (mean CA = 71.6 months). It was found that children who have learned to anticipate an invariant cue-reward relation in such tasks manifest improved hypothesis-testing behavior, as well as improved discrimination performance, whereas children who have been trained to identify and name the various stimulus components of the discriminanda do not perform better than those without such training. It was also found that children who have had practice in shifting from an irrelevant to a relevant dimension perform better than those who have not had such experience. Moreover, children who have been given explicit instruction and training in the use of win-stay and lose-shift rules, as well as in the use of valid hypotheses, manifest strategies superior to those without such training. Finally, extensive pretraining over two sessions, administered on separate days, resulted in a marked reduction in the proportion of children who were dimensionally fixated while solving discrimination problems with two genuine dimensions.     

Introtacts as predictors of discrimination performance in kindergarten children

Kindergarten children were given simultaneous discrimination tasks with two irrelevant dimensions varying within settings. Prior to each block of eight feed-back trials, the children were asked to attempt to provide a statement of the solution. The introtacts thus provided were found to have several of the desirable characteristics that have been reported for older children with either introtact or blank-trial probes, but which have not been found previously for kindergarten children with the blank-trial probe. Classification of the children according to the trial block on which they first verbalized the correct relevant dimension was found to account for more than 60% of the total variability in discrimination performance. The introtacts were also used to assign parameters to theoretical prediction equations, with nearly two-thirds of the total variability in discrimination performance accounted for by the theory. Extension of the method to other models is discussed.     

There's method in our madness: Interpersonal attraction as a multidimensional construct

The convergent validity and number of dimensions common to six measures of interpersonal attraction (three verbal and three nonverbal) were explored in this investigation. Convergent validity was found within verbal and nonverbal modes of measurement, but not between modes. No general factor was found to be common to the six measures of attraction. It was, therefore, concluded that method bias influences experimental results, threatening the comparability of results from research programs using different modes of measuring attraction. The results also question the assumption that social attitudes, such as attraction, are closely related to behavior, and imply that predictions derived from theories based on different modes of measuring attraction will have unequal utility.     

Altering the Shape of Punishment Distributions Affects Decision Making in a Modified Iowa Gambling Task

Neuroeconomics research has shown that preference for gambling is altered by the statistical moments (mean, variance, and skew) of reward and punishment distributions. Although it has been shown that altered means can affect feedback‐based decision making tasks, little is known if the variance and skew will have an effect on these tasks. To investigate, we systematically controlled the variance (high, medium, and low) and skew (negative, zero, and positive) of the punishment distributions in a modified version of the Iowa Gambling Task. The Iowa Gambling Task has been used extensively in both academic and clinical domains to understand decision making and diagnose decision making impairments. Our results show that decision making can be altered by an interaction of variance and skew. We found a significant decrease over trials in choices from the decks with high variance and asymmetrically skewed punishments and from the decks with low variance and zero skew punishments. These results indicate that punishment distribution shape alone can change human perception of what is optimal (i.e., mean expected outcome) and may help explain what guides our day‐to‐day decisions. Copyright © 2013 John Wiley & Sons, Ltd.     

A validation of a computerised task of risk-taking and moral decision-making and its association with sensation-seeking,impulsivity and sociomoral reasoning

The aim of this study was to investigate the reliability and validity of the computer based application of the Secret Agent (SA) task of risk-taking and moral decision-making. The participants were 100 male patients in a maximum security hospital (50 with severe mental illness and 50 with personality disorder) and 50 community based healthy controls. All participants completed the SA task, the Iowa Gambling Task (IGT), and measures of IQ, antisocial personality traits, sensation-seeking, impulsivity and sociomoral reasoning. The SA risk-taking and moral decision-making scales had satisfactory levels of reliability (Cronbach’s alpha). Risk-taking correlated significantly with sensation-seeking across all three participant groups. In contrast, risk-taking only correlated with impulsivity among the severe mental illness group. Moral decision-making correlated with sociomoral reasoning among the personality disorder group. No correlation was found between the SA scores and the IGT score and the IGT did not correlate with sensation-seeking or impulsivity. IQ and antisocial personality traits did not correlate with the SA or IGT scales. The study highlights the importance of context, the nature of the risk-taking task, and ‘problem framing’ of the instructions in their relationship with individual differences.     

Developmental changes of win-stay and loss-shift strategies in decision making

This study aims to clarify the developmental changes in real-life decision making when strategy is adjusted using both positive and negative feedback, that is, whether strategic adjustment evolves with age. A total of 84 participants divided into three age groups (children, adolescents, and adults) performed the standard version of the Iowa Gambling Task (IGT). Children and adolescents showed a strong bias in favor of disadvantageous choices whereas adults learned to decide advantageously during the course of the task. Interestingly, the results clearly demonstrate that children did not switch differently following gains and losses whereas adolescents and adults switched more often after a loss than after a gain, corresponding to the “loss-shift” and the “win-stay” strategies, respectively. The results also revealed that adults switched less often after losses compared to children and adolescents and, thus, used the loss-stay strategy more often than the 2 youngest groups. These new findings suggest that successful completion of the IGT by adults requires fine feedback monitoring and more frequent use of the win-stay and loss-stay strategic adjustments.     

Types produce types: An examination of personality development using Holland's theory

This study was designed to test Holland's hypothesis that parents encourage the development of their own personality types in their offspring. Data were collected by personal interviews from three freshmen classes at a large midwestern university. Parent's personality types (occupations) were compared to offsprings' personality types (expressed occupational choices) using the Kolmogorov-Smirnov one-sample test to determine whether or not the comparisons were due to chance. The results indicated that relationships existed between the personality types of fathers-sons, fathers-daughters and mothers-daughters while no relationship was confirmed between mothers-sons.