Stimulus probability and prediction outcome as determinants of choice reaction time: Some procedural considerations

Effects of stimulus probability and prediction outcome on two-choice reaction speed (CRS) were determined when a frequency imbalance was reversed half-way through 300 samples of a 70/30 stimulus distribution and when the same 70/30 distribution was sampled for 1200 trials. Prior to each presentation Ss made a prediction; following each presentation Ss identified the stimulus by pressing a right-hand or left-hand trigger. CRS was faster to correctly predicted stimuli, and faster to the more probable stimulus. Ss who were informed of the frequency imbalance reacted significantly faster than Ss who were not. Both practice and boredom effects were demonstrated by using the extended number of trials. CRS was faster during the second session of 300 trials than during the first; after two sessions, CRS was slower during the second half of two additional sessions.     

Contextual determinants of retrieval in three-month-old infants

Three-month old infants learned to kick to produce movement in an overhead crib mobile on a conjugate reinforcement (FRI) schedule. All infants were trained in the presence of one of two distinctive crib bumpers. In Experiment 1, infants receiving cued-recall tests in the presence of the original training bumper remembered the conditioned association 1 week later, but those tested in the presence of a different bumper did not. Two weeks later, neither training group evidenced retention of the contingency. In Experiment 2, infants who received a 3-min exposure (“a reactivation treatment”) to the original training bumper 24 h prior to the 2-week retention test exhibited excellent long-term retention, whereas those exposed to a different bumper as a reminder did not, irrepective of whether it was identical to the test bumper or not. These findings demonstrate that the context alone, even though it was never exclusively paired with reinforcement, can act as a retrieval cue.     

Testing the limits of optimistic bias: event and person moderators in a multilevel framework

N. D. Weinstein (1980) established that optimistic bias, the tendency to see others as more vulnerable to risks than the self, varies across types of event. Subsequently, researchers have documented that this phenomenon, also known as comparative optimism, also varies across types of people. The authors integrate hypotheses originally advanced by Weinstein concerning event-characteristic moderators with later arguments that such optimism may be restricted to certain subgroups. Using multilevel modeling over 7 samples (N = 1,436), the authors found that some degree of comparative optimism was present for virtually all individuals and events. Holding other variables constant, higher perceived frequency and severity were associated with less comparative optimism, higher perceived controllability and stereotype salience with more comparative optimism. Frequency, controllability, and severity were associated more with self-risk than with average-other risk, whereas stereotype salience was associated more with average-other risk than with self-risk. Individual differences also mattered: comparative optimism was related negatively to anxiety and positively to defensiveness and self-esteem. Interaction results imply that both individual differences and event characteristics should jointly be considered in understanding optimistic bias (or comparative optimism) and its application to risk communication.     

Traditionality of choice and sex-role identification as moderators of the congruence of occupational choice in college women

This study examined the relationship of traditionality of occupational preferences and sex-role orientation to personality-occupational environment congruence in college women. Three-letter Holland personality codes were obtained for each of 184 college women based on same-sex normative scores from the Strong-Campbell Interest Inventory and on scores from the ACT Unisex Interest Inventory (UNIACT). Subjects' occupational preferences were classified as traditional, moderately traditional, or nontraditional based on the percentages of women in the occupation. Scores on the Bern Sex Role Inventory were used to classify subjects into one of four sex-role categories. Results indicated a strong association between congruence and traditionality of choice; women whose choices were in nontraditional career fields were significantly more likely to be making choices congruent with their personality type than were women choosing traditional career fields. Further, while sex-role orientation was not significantly related to either congruence or traditionality, masculine-typed women were most likely to make nontraditional and congruent career choices, while the majority of feminine-typed, androgynous, and undifferentiated women stated preferences for traditional career fields. Implications for the applicability of Holland's congruence postulate to women's vocational behavior are discussed.     

Perceptions of daily sacrifice motives: Accuracy,bias, outcomes,and moderators

The current study examined accuracy and bias in perceptions of a partner’s daily approach and avoidance sacrifice motives, associations of bias with daily sacrificer and perceiver relationship quality, and moderators of accuracy (gender, relationship length, daily stress). 94 cohabiting couples completed daily measures of sacrifice (N = 375 days), stress, relationship satisfaction, and closeness. People showed evidence of accuracy for partner sacrifice motives, but accuracy for approach sacrifice depended on relationship length. People underperceived partner sacrifice motives; underperception of approach sacrifice was associated with greater sacrificer closeness, while overperception of approach sacrifice and overperception of avoidance sacrifice was associated with greater perceiver closeness, although these effects were small. Gender and stress did not moderate tracking accuracy or mean-level bias.     

Response bias and the measurement of choice alternation

The problem of devising a measure of alternation of choices that is independent of response bias is considered. Previous solutions are equivalent to the correction for chance guessing in the Yes/No experiment of psychophysics, and require an estimate of response bias, usually from choices on the first of two daily trials. This involves the questionable assumption that response bias is homogeneous over time or across subjects. It is suggested that spontaneous alternation is analogous to the two alternative forced choice situation of psychophysics, and the fourfold point correlation is proposed as an index of alternation that is statistically independent of response bias. Implications for interpreting the effect upon spontaneous alternation of hippocampal and other lesions are considered.     

Contextual determinants of mothers' interventions in young children's peer interactions

In this study, the role of context in mothers' interventions in their preschool children's peer relationship problems was investigated. Event theme (aggression, peer rebuff, or initiating play), the child's role in the event (actor or target), the child's age and sex, and the mother's emotional reaction were examined as predictors of the extent to which mothers (N = 71) said they would discuss peer relationships, encourage peer interaction, and use power assertion in response to a series of videotaped vignettes depicting common peer relationship problems. Mothers suggested using more discussion in aggressive situations and more encouragement in initiating play situations. Mothers said they would use more power assertion when the child was the actor (i.e., provocateur), rather than the target, in an aggressive situation. Findings are discussed in terms of (a) the importance of considering context in understanding how mothers intervene in their children's peer relationships and (b) the need to examine moderators of cross-contextual consistency in mothers' interventions.     

Contextual influences on phonetic identification in aphasia: the effects of speaking rate and semantic bias

Two experiments examined the influence of context on stop-consonant voicing identification in fluent and nonfluent aphasic patients and normal controls. Listeners were required to label the initial stop in a target word varying along a voice onset time (VOT) continuum as either voiced or voiceless ([b]/[p] or [d]/[t]). Target stimuli were presented in sentence contexts in which the rate of speech of the sentence context (Experiment 1) or the semantic bias of the context (Experiment 2) was manipulated. The results revealed that all subject groups were sensitive to the contextual influences, although the extent of the context effects varied somewhat across groups and across experiments. In addition, a number of patients in both the fluent and nonfluent aphasic groups could not consistently identify even endpoint stimuli, confirming phonetic categorization impairments previously shown in such individuals. Results are discussed with respect to the potential reliance by aphasic patients on higher level context to compensate for phonetic perception deficits.     

Human reasoning: Some possible effects of availability

This paper discusses some possible ways in which the availability heuristic (Tversky and Kahneman, 1973) may mediate subjects' responses to experimental ‘reasoning’ tasks. A brief review of some effects of availability in other areas is given and then the application of availability to reasoning data is considered with respect to problems employing both ‘thematic’ and ‘abstract’ content.In the case of thematic content, it is argued, with reference to a variety of studies, that to produce a differential effect (to abstract content), the content must provide available cues, resulting from the subjects' experience. Differential effects of content are thus interpreted as differential effects of availability. When abstract content is used, there are cues available from the experimental situation itself, and it is shown that several known error tendencies readily lend themselves to an explanation in terms of availability.In the final section, it is pointed out that a focus on available cues, rather than logical structure, provides a psychological, rather than logical, approach to human reasoning. It is argued that a bias may be psychologically, although not logically, optimal in that it may often produce correct responses in ‘real life’. Accordingly, the possible real life utility of availability is considered, and several ways in which the bias may lead to usually correct decisions are discussed. Given this, it is argued that availability is an effective heuristic and that observed biases on a range of experimental tasks may thus be interpreted as resulting from the application of a behavior that is optimal within the limits of human cognition. However, it is concluded that limitations in both deterministic and probabilistic problem solving may lead to a consistent, but erroneous, view of the world.     

On some determinants of choice in pigeons

A pigeon's pecking at each of two or three simultaneously available red keys was reinforced at different frequencies with a conditioned reinforcer, an orange key, on which 25 pecks resulted in a presentation of grain. Pecking was occasionally punished with a period of no reinforcement during which each key was dark. Both with two and with three keys, the relative frequency of pecking on a key was equal to the relative frequency of reinforcement obtained by pecks on that key. Also, the absolute frequency of pecking on each key was a linear function with zero intercept of the absolute frequency of reinforcement associated with that key. The slope of this function varied with the number of available keys; it was steeper with two than with three. The relative frequency of switching from any key (two successive pecks on different keys) approximated a linear function with zero intercept and slope slightly greater than 1.0 of the total relative frequency of reinforcement associated with the keys to which the bird could switch. However, the relative frequency of switching to a particular key often showed systematic irregularities. The invariance in these data is the equality between the relative frequency of pecks on one of two or three keys and the relative frequency of reinforcement associated with that key.     

Contextual moderation of racial bias: the impact of social roles on controlled and automatically activated attitudes

Three experiments tested the hypothesis that the social roles implied by specific contexts can attenuate or reverse the typical pattern of racial bias obtained on both controlled and automatic evaluation measures. Study 1 assessed evaluations of Black and Asian faces in contexts related to athlete or student roles. Study 2 compared evaluations of Black and White faces in 3 role-related contexts (prisoner, churchgoer, and factory worker). Study 3 manipulated role cues (lawyer or prisoner) within the same prison context. All 3 studies produced significant reversals of racial bias as a function of implied role on measures of both controlled and automatic evaluation. These results support the interpretation that differential evaluations based on Race x Role interactions provide one way that context can moderate both controlled and automatic racial bias.     

Contextual determinants of anger and other negative expressions in young infants

Two experiments examined how different frustration contexts affect the instrumental and emotional responses of 4- to 5-month-old infants. Three different frustrating contexts were investigated: loss of stimulation (extinction), reduction in contingent stimulation (partial reinforcement), and loss of stimulus control (noncontingency). In both experiments, changes in arm activity and facial expressions of anger and sadness coded according to the Maximally Discriminative Facial Movement Coding System (MAX) were the measures of frustration. Both experiments showed that (a) arm responses increased when the contingent stimulus was lost or reduced but decreased when control of the stimulus was lost under noncontingency, (b) MAX-coded anger, but not MAX-coded sad or blends of anger and sad, was associated with frustration, and (c) the pattern of anger and arm responses varied with the frustration context. When contingent stimulation was lost or reduced, both anger and arm responses increased, but when expected control was lost under noncontingency, arm responses decreased while anger increased.