EQUATING INVERSE PROBABILITIES IN IMPLICIT PERSONALITY JUDGMENTS

Abstract— Meehl and Rosen (1955) observed that their colleagues tended to equate the sensitivity of a sign (its probability given a diagnostic category) with its predictive accuracy (the probability of the diagnostic category given the sign). Such equating of inverse probabilities implies ignoring base rates. Later, many researchers demonstrated such neglect in a number of experimental contexts involving hypothetical judgments; others have found some use of base rates—but only when base rates were supplied by the experimenter, in which case even irrelevant base rates influenced judgment. The present study tested for equating conditional probabilities in a context similar to the contexts involved in the initial observations—that is, subjects strove for accuracy rather than attempted to make good judgments about hypothetical problems, and the base rates were generated by the subjects themselves. Neglect of base rates was revealed by within-individual comparisons showing subjects equated inverse probabilities without equating the corresponding unconditional ones.     

The object-line inferiority effect in pigeons

Eight pigeons (Columba livia) were trained to discriminate between diagonal lines presented alone or embedded in a redundant L-shape right-angle form. The stimuli were white and were presented in an environment that was otherwise totally dark. Numerous experiments done with human observers have shown a strong superiority effect when the diagonal lines are embedded in redundant contexts. However, in Experiment 1 ofthe present study, the pigeons discriminated significantly better between the two diagonal lines when presented alone than when they were embedded in the right-angle context. In order to check on the possibility that these results were restricted to the semi-Ganzfeld condition of Experiment 1, a second experiment was done with black stimuli presented on a white background. Results of Experiment 2 also showed a strong distractor effect. The results of the present experiments confirmed the predictions of the Heinemann and Chase model of pattern recognition by pigeons.     

Semantics and the computational paradigm in cognitive psychology

There is a prevalent notion among cognitive scientists and philosophers of mind that computers are merely formal symbol manipulators, performing the actions they do solely on the basis of the syntactic properties of the symbols they manipulate. This view of computers has allowed some philosophers to divorce semantics from computational explanations. Semantic content, then, becomes something one adds to computational explanations to get psychological explanations. Other philosophers, such as Stephen Stich, have taken a stronger view, advocating doing away with semantics entirely. This paper argues that a correct account of computation requires us to attribute content to computational processes in order to explain which functions are being computed. This entails that computational psychology must countenance mental representations. Since anti-semantic positions are incompatible with computational psychology thus construed, they ought to be rejected. Lastly, I argue that in an important sense, computers are not formal symbol manipulators.     

Masturbation from Judaism to Victorianism

This article demonstrates how masturbation, based on a misconception of Genesis 38:7–10, was judged harshly in both Judaism and Christianity, laying the foundation historically for social and religious hostility toward sex. Masturbation, known as the secret sin, a threat to the human race, and an ontic evil, was condemned officially in 1054 by Pope Leo IX.From the medieval era to Victorianism there evolved new distortions of religion and science, so that masturbation was regarded as unnatural sex, murder, a diabolical practice, and the cause of two-thirds of all diseases and disorders including insanity, neurosis, and neurasthenia. Masturbation has historically served as the catalyst for social change in sexual attitudes.     

Psychosocial factors in heart surgery: presurgical vulnerability and postsurgical recovery

OBJECTIVE: Distress and low perceived social support were examined as indicators of psychosocial vulnerability in patients about to undergo heart surgery. Design: A total of 550 study patients underwent heart surgeries, including bypass grafting and valve procedures. Psychosocial interviews were conducted about five days before surgery, and biomedical data were obtained from hospital records. MAIN OUTCOME MEASURES: Sociodemographic, personality, religious, and biomedical factors were evaluated as predictors of psychosocial vulnerability, and all five sets of variables were evaluated as contributors to hospital length of stay (LOS). RESULTS: Patients scoring higher on one or more indicator of presurgical psychosocial vulnerability were younger, more likely to be female, less likely to be married, less well educated, lower in dispositional optimism, higher in trait anger, and lower in religiousness. Older age, depression, low support, and low trait anger each showed an independent, prospective association with greater LOS, and several other predictors had prospective relationships with LOS that were statistically mediated by depression or perceived support. CONCLUSION: Evidence that multiple psychosocial factors may influence adaptation to heart surgery has implications for understanding and ameliorating presurgical distress and for improving postsurgical recovery.     

Quantifying Intervention Intensity: A Systematic Approach to Evaluating Student Response to Increasing Intervention Frequency

Response to intervention (RTI) has been discussed as a new model of assessment. Although the basic process by which RTI works has received frequent attention in the literature, the available research leaves several important questions unanswered (Kavale et al. in Learn Disabil Q 28(1): 2–16, 2005). One concept within RTI that has received little empirical consideration is intervention intensity. The purpose of this study was to evaluate the impact of the application of increased intervention frequency on the mathematics performance of students and to evaluate this increased frequency as a systematic means of increasing and quantifying intervention strength. Results indicate that although all students were responsive to the intervention, some participants were sensitive only to more frequent application of the treatment or at more intense levels of treatment. Through this methodology a means of quantifying treatment intensity was also identified and implications for future research are discussed.     

Paying for sanctions in social dilemmas: The effects of endowment asymmetry and accountability

The present research examines whether or not endowment asymmetry leads those with many endowments to contribute more than those with few endowments towards the public good (i.e., a first-order dilemma), but also towards the implementation of a sanctioning system (i.e., a second-order dilemma). In Experiment 1, we found that those with many endowments contributed more than those with few endowments in a public good dilemma without a sanctioning system present, whereas those with many endowments did not contribute more than those with few endowments toward the implementation of a sanctioning system. The latter effect, however, was eliminated when participants were accountable (i.e., when expectations that they would have to justify their decisions to others in the group were high). Experiment 2 showed that when participants were accountable, the contributions of those with many endowments (and not those with few endowments) toward the sanctioning system increased, but only when they perceived the group to be more self-evaluative in terms of morality (i.e., high-evaluation expectancy). Experiment 3 showed that this effect of evaluation expectancy only emerged when participants were accountable to the whole group rather than to only one group member.     

Evaluations of presidential performance: Race, prejudice, and perceptions of Americanism

Earlier research suggests that despite President Obama's election, racial prejudice persists and continues to shape reactions to his presidency. The current work examines the role of Whites’ prejudice in shaping perceptions of Obama's Americanism, and ultimately evaluations of his performance. Specifically, this research proposes that “how American” Obama is perceived will mediate the relationship between racial prejudice and evaluations of his performance for White, but not Black participants and only for Obama and not for Vice-President Biden. Data were collected from 295 Black or White students surveyed 1 year after Obama's election. Supportive of our hypotheses, racial prejudice predicted Whites’ negative evaluations of Obama's performance, and this relationship was mediated by how American Obama was perceived. Additionally, these relationships were not obtained among Black participants or when Blacks or Whites evaluated the Americanism and job performance of Vice-President Biden.