Absolute and Relative Biases in Estimations of Personal Risk1

Two studies examined the accuracy of personal risk estimates, as determined by comparing mean estimates made by college students with population statistics for college-educated individuals. Study 1 suggested that optimistic biases (the tendency for people to think they are less at risk than the average person) arise more because people overestimating the average person's risk than because they underestimate their own risk. In Study 2, subjects rated their risk after being presented with risk statistics that were 150%, 100%, or 50% of the true values. Subjects' estimates decreased with decreases in the comparison statistics, as if subjects attempted to preserve their “below-average” status, but they changed less than did the statistics and were actually pessimistic in comparison to the 50% values. Implications for interventions designed to influence risk perceptions are discussed.     

TESTING A HIERARCHICAL MODEL OF SELF-KNOWLEDGE

Abstract— A priming procedure (e g, Klein, Loftus Trafton, & Fuhrman, 1992) was used to lest a hierarchical model of self-knowledge. According lo this model, people simultaneously hold multiple representations of themselves that differ bath in their context specificity and in the type of knowledge of which they consist Specifically, context-independent self-knowledge is assumed to be represented abstractly without reference to any particular behaviors, whereas the representation of context-dependent self-knowledge includes knowledge of one's behavior in specific situations. Our results support a hierarchical model. Subjects accessed abstract knowledge when describing their context-independent personality characteristics, but accessed behavioral episodes when describing themselves in a specific context Possible implications of this research are discussed, as a the relation of a hierarchical model of self-knowledge to a mixed model of self-knowledge (e g, Klein & Loftus, 1993b).     

Chronometric analysis of apparent spotlight failure in endogenous visual orienting

Subjects made speeded responses to peripheral luminance increments or decrements preceded by informative central precues. In 4 experiments one of these stimuli was much more likely to occur than the other. In a simple detection task, the likely and unlikely stimuli showed equivalent cuing effects. In a discrimination task (bright/dim), the likely stimuli showed cuing but the unlikely one did not (spotlight failure), and there was a tendency to make the likely response when the unlikely stimulus occurred at the cued location. In Experiment 5, the 2 stimuli were equally likely, and a choice was required. Large cuing effects were observed for both stimuli with no evidence of a speed-accuracy trade-off. A logogen-activation framework is described within which criterion and sensitivity adjustments are needed to accommodate the full pattern of results. Endogenous orienting appears to enhance processing of all stimuli at attended (relative to unattended) locations, an effect that may be masked by specific stimulus or response expectancies.     

Effects of arousal on human visual dominance

Human attention research has found that vision controls attention when competing against other sensory modalities, for example, audition, proprioception, taction. Similarly, animal learning experiments have demonstrated visual attentional control when animals are positively motivated but auditory control when aversively motivated. The experiments with animals suggest a way of attenuating visual dominance in humans. Three experiments using human subjects explored the degree of visual versus auditory control exhibited in the presence of different arousal states. In Experiments 1 and 2, an electric shock and a threat of electric shock, respectively, to the subject’s finger resulted in auditory attentional control In Experiment 3, a tactile stimulus resulted in attenuated visual control. The results of these experiments are discussed in relation to the evolutionary advantage conferred by such attentional strategies.     

The reliability of a computer interview for drug use/abuse information

A computer interview was developed to collect information about drug use/abuse from high school students. Responses to this interview were compared with those obtained from an identical paper-and-pencil questionnaire given to the same students, in counterbalanced order. Results were comparable for the two methods, but missing data and logically inconsistent answers obtained with the paper-and-pencil questionnaire were not possible with the computer interview. The overwhelming majority of respondents preferred the computer interview as a means of data collection.     

Motivations for childbearing and fertility behavior among urban and rural families of Iran

A sample of 384 husbands and wives were randomly selected and interviewed to investigate the implication of fertility norms and motivations for childbearing on fertility and family planning behavior among Iranian families in urban and rural areas of Iran, after the Islamic Revolution of 1979. The term "fertility behavior" refers to actual family size, which is defined as number of children the respondent has living at the time of the interview. "Family planning behavior" refers to the duration of time that the subject has used any birth control method(s). Rural families demonstrated larger actual and ideal family sizes than urban families. The rural sample had a median actual family size of 3.5 children and a median ideal family size of 4.7 children. For the urban sample these figures were 2.2 and 2.3, respectively. The median number of years married was 12.33 for rural and 13.91 for urban respondents. Urban respondents tended to emphasize the psychological and emotional benefits and liabilities associated with having children while rural respondents tended to emphasize both economic and security related motivations. Both groups endorsed infant mortality as a motivation for having more children. Male and female respondents were remarkably similar in their endorsed motivations. There was a significant positive correlation between desired and ideal family size. The correlations among ideal/desired family size and practicing birth control methods were the same and significant at the .001 level. The relationship between motivations for childbearing and years of practicing birth control methods was also significant at the .001 level. Stepwise regression analyses were performed to examine the important predictors of fertility and family planning behavior. For both actual family size and years on birth control, males and females were very similar in terms of predictor importance. Those respondents with less education and large ideal family size tended to have larger actual family size. Location (urban/rural) and parents, family size was weighted much more heavily for males than for females. Those respondents with greater education and who lived in an urban areas tended to have used birth control for longer periods of time. Ideal family size did not contribute significantly to this regression. Parents' family size and motivations for childbearing made marginal contributions to regressions on either dependent variable.     

Coherency in children's discourse

We provide evidence that the capacity of young children to engage in social interaction exceeds that suggested by Piaget (1926). Rather than being collective monologues, the conversations between the subjects of this study (twin boys) were dialogues: the children attended to one another's utterances and provided relevant responses. This was observed for conversations which were referentially based as well as for sound play exchanges. This is not to say that the children experienced no difficulty in sustaining cooperative discourse. It could take a speaker several turns to secure the attention of the coconversationalist and establish a discourse topic.     

Effects of response-shock interval and shock intensity on free-operant avoidance responding in the pigeon

Two experiments investigated free-operant avoidance responding with pigeons using a treadle-pressing response. In Experiment I, pigeons were initially trained on a free-operant avoidance schedule with a response-shock interval of 32 sec and a shock-shock interval of 10 sec, and were subsequently exposed to 10 values of the response-shock parameter ranging from 2.5 to 150 sec. The functions relating response rate to response-shock interval were similar to the ones reported by Sidman in his 1953 studies employing rats, and were independent of the order of presentation of the response-shock values. Shock rates decreased as response-shock duration increased. In Experiment II, a free-operant avoidance schedule with a response-shock interval of 20 sec and a shock-shock interval of 5 sec was used, and shock intensities were varied over five values ranging from 2 to 32 mA. Response rates increased markedly as shock intensity increased from 2 to 8 mA, but rates changed little with further increases in shock intensity. Shock rates decreased as intensity increased from 2 to 8 mA, and showed little change as intensity increased from 8 to 32 mA.