Overconfidence and underconfidence: When and why people underestimate (and overestimate) the competition

It is commonly held that people believe themselves to be better than others, especially for outcomes under their control. However, such overconfidence is not universal. This paper presents evidence showing that people believe that they are below average on skill-based tasks that are difficult. A simple Bayesian explanation can account for these effects and for their robustness: On skill-based tasks, people generally have better information about themselves than about others, so their beliefs about others’ performances tend to be more regressive (thus less extreme) than their beliefs about their own performances. This explanation is tested in two experiments that examine these effects’ robustness to experience, feedback, and market forces. The discussion explores the implications for strategic planning in general and entrepreneurial entry in particular.     

Comprehension skill, inference-making ability, and their relation to knowledge

In this study we investigated the relation between young children's comprehension skill and inference-making ability using a procedure that controlled individual differences in general knowledge (Barnes & Dennis, 1998; Barnes, Dennis, & Haefele-Kalvaitis, 1996). A multiepisode story was read to the children, and their ability to make two types of inference was assessed: coherence inferences, which were essential for adequate comprehension of the text, and elaborative inferences, which enhanced the text representation but which were not crucial to understanding. There was a strong relation between comprehension skill and inference-making ability even when knowledge was equally available to all participants. Subsidiary analyses of the source of inference failures revealed different underlying sources of difficulty for good and poor comprehenders.     

Selective Retention of Information about the Superficial Form of Text: Ellipses W ith Antecedents in Main and Subordinate Clauses

Elliptical verb phrases must be interpreted indirectly, using a representation of the surface form of nearby (usually preceding) text. We used this fact to demonstrate the different availability of superficial representations of the two clauses in main-subordinate pairs. The acceptability of a later ellipsis was reduced when it took its meaning from a main clause that was followed by a subordinate clause, as compared with other combinations. In addition, positive acceptability judgements were made more quickly (1) when the antecedent clause was subordinate, rather than main, suggesting that the superficial form of a subordinate clause is more important, and (2) when the antecedent was in the immediately preceding clause, rather than two clauses back. These results support the idea that the surface form of subordinate clauses is selectively retained until the corresponding main clause has been read, but the surface form of a main clause is not retained after it has been interpreted.     

Learned helplessness in humans: A developmental analysis

The investigation of learned helplessness (LH) in children is integrated with (a) research on LH in adults and (b) basic developmental research relating to the processes which theoretically mediate LH. It is concluded that developmental changes in perceptions of noncontingency, causal understanding, and expectations of future noncontingency are all likely to influence the process whereby children of different ages manifest LH. Several sets of hypotheses relating to each of these variables are presented. In addition, it is argued that developmental research on LH should examine the relationship between the components of the attributional reformulation of LH and should be explicit about the conceptual status of these variables. Finally, several approaches to understanding the origins of individual differences in LH are evaluated. It is proposed that exposure to noncontingency, performance feedback, modeling, and parental attributions may each contribute to the ontogenesis of individual differences in LH.     

Primary prevention of catastrophic injury.

Motor vehicle crashes are a leading cause of injury and death until age 45. Efforts to prevent these injuries have largely followed the dictates of the public health movement focusing on interventions for entire communities or regulatory statutes. Individual interventions, more congruent with traditional psychological approaches, have been rare. This article argues that a blending of these two approaches is warranted. Evaluation of prevention programs should focus on multiple levels including the individual, the community, and regulatory processes. Identification of subgroups of adolescents and young adults with unique psychological and behavioral dispositions regarding injury must be paired with realistic interventions of adequate duration.     

Odor intensity after self-adaptation and cross-adaptation

Psychophysical functions for the odor intensity of n-propanol and n-pentanol were obtained after no adaptation and after self-adaptation and cross-adaptation. Adaptation caused the psychophysical function to become steeper and generally concave downward in log-log coordinates. Increase in the in tensity of a: self-adapting stimulus produced relatively greater increases in the steepness of the functions than did increases in adapting duration. A comparison between the odorants revealed that propanol and pentanol have equal self-adapting effects when their respective adapting concentrations are matched for subjective intensity. Cross-adaptation had approximately the same effect as self-adaptation on the form of the psychophysical function, but a cross-adapting stimulus of a specified subjective intensity was less effective than a self-adapting stimulus of the same intensity. Adaptation to pentanol caused a larger reduction in the perceived intensity of propanol than adaptation to propanol caused in the perceived intensity of pentanol.     

Changes in HIV treatment beliefs and sexual risk behaviors among gay and bisexual men, 1997-2005.

OBJECTIVE: Beliefs about HIV treatment effectiveness and the impact of HIV treatments on HIV transmission risks were initially related to sexual risk-taking in the late 1990s when multidrug HIV treatments first became available. This study examined changes in beliefs about the effects of HIV treatment for preventing HIV transmission and their association to sexual risk behaviors between the years 1997 and 2005. DESIGN: Anonymous surveys were administered to a convenience sample of gay and bisexual men attending a large community event in Atlanta, Georgia in 1997 (N = 498) and again at the same community event in 2005 (N = 448). Analyses were performed for men living with HIV/AIDS and for men who have not been diagnosed with HIV/AIDS. MAIN OUTCOME MEASURES: Rates of unprotected anal intercourse in the previous 3 months. RESULTS: There were significant increases in high-risk sexual practices that coincided with increased beliefs that HIV treatments can reduce the chance of transmitting HIV. However, optimistic beliefs about the health benefits of HIV treatments decreased over the 8 years and were not related to risk behaviors. CONCLUSIONS: Beliefs about how HIV treatments impact HIV infectiousness remain associated with HIV transmission risk behavior and interventions targeting at-risk as well as HIV-positive men who have sex with men must directly address these beliefs and perceptions.