Shape from stereo: A systematic approach using quadratic surfaces

We used quadratic shapes in several psychophysical shape-from-stereo tasks. The shapes were elegantly represented in a 2-D parameter space by the scale-independentshape index and the scale-dependentcurvedness. Using random-dot stereograms to depict the surfaces, we found that the shape of hyperbolic surfaces is slightly more difficult to recognize than the shape of elliptic surfaces. We found that curvedness (and indirectly, scale) has little or no influence on shape recognition.     

Genetic and Environmental Effects on Openness to Experience, Agreeableness, and Conscientiousness: An Adoption/Twin Study

ABSTRACT Previous research has indicated that extraversion and neuroticism are substantially affected both by genotype and environment. This study assesses genetic and environmental influences on the other three components of the five-factor model of personality: Openness to Experience, Agreeableness, and Conscientiousness. An abbreviated version of the NEO Personality Inventory (NEO-PI) was administered to 82 pairs of identical twins and 171 pairs of fraternal twins reared apart and 132 pairs of identical twins and 167 pairs of fraternal twins reared together. Estimates of genetic and environmental effects for Openness and Conscientiousness were similar to those found in other studies of personality: Genetic influence was substantial and there was little evidence of shared rearing environment. Results for Agreeableness were different: Genetic influence accounted for only 12% of the variance and shared rearing environment accounted for 21% of the variance. Few significant gender or age differences for genetic and environmental parameters were found in model-fitting analyses.     

Social context and perceived task difficulty as mediators of depressive self-evaluation

This study examined two separate, but potentially interactive, influences on depressive self-evaluation: social context and perceptions of task difficulty. First, it was hypothesized that, if negative self-evaluations of depressed individuals are motivated by a desire to elicit attention and sympathy from others, depressed subjects should evaluate themselves more negatively than nondepressed subjects in a public setting, but not when they make self-evaluative judgments in private. Second, it was hypothesized that negative self-evaluation results from a bias to perceive tasks as being intrinsically easy, i.e., if a task is easy, a given score would be evaluated more poorly than if the task were difficult. It was found that the self-evaluations of depressed subjects were influenced by the social context, but not always in a negative direction. Depressed subjects did not differ from nondepressed subjects when performance evaluations were made in private. In a public condition, depressed subjects evaluated themselves more negatively than nondepressed subjects following an easy task, but evaluated themselves more positively following a difficult task. Depressed subjects did not evidence a bias to perceive tasks as being intrinsically easy. Depressed subjects did rate the tasks to be more difficult for themselves than they thought they would be for others and this expectancy was predictive of negative self-evaluation. These results were discussed in terms of alternative self-presentation motives and theories of social cognition. Self-evaluation often involves social comparison and researchers need to attend to the potentially complex interactions among social and cognitive processes.I would like to thank Deborah Davis and Paul Westerholm for their help in data collection, Ruth Maki for her statistical expertise, and the anonymous reviewers for their thoughtful comments. Portions of this paper were presented at the Annual Convention of the American Psychological Association, New Orleans, 1989.     

“That man’s father is my father’s son”: The roles of structure,strategy, and working memory in solving convoluted verbal problems

Normative data (N=896) collected on solutions to the traditional reasoning problem “Brothers and sisters have I none,/That man’s father is my father’s son” was the platform for a set of experiments to investigate the roles of problem structure, subject strategy, and working memory in error making in a class of verbal problems. The normative data revealed that the modal, but incorrect response to the brothers and sisters problem was “himself,” whereas the correct response of “son” was given by only 17% of subjects for the traditional version above, rising to 40% for a reordered novel version. This problem’s structure, identified as adouble-modifier structure, was found to produce similar response patterns across a range of verbal problems. Results from (1) syntactical structure manipulations (e.g., “My father’s son is the father of that man”), and (2) efforts to teach subjects to use a linear strategy (a sequence of steps), interpreted within a framework of Just and Carpenter’s (1992) capacity theory of comprehension, suggested that working memory overload varies across within-structure modifications and subjects. Further-more, this overload may be compounded by subjects’ choices of strategy.     

Gender roles,computer attitudes,and dyadic computer interaction performance in college students

Females tend to score lower than males on measures of computer aptitude and attitudes. This study examined the potential effects of several mediating factors, sex of experimenter, sex of experimental partner, sex typing (Bem Sex Role Inventory score), and level of past experience, on a computer interaction task involving a dyad. College students, drawn from a primarily white college population, after completing paper-and-pencil measures assessing computer experience, computer attitudes, and gender roles, participated in a computer task involving drawing up to ten prescribed geometric patterns on a computer screen. Research assistants recorded the number of correctly completed patterns and videotaped participant interaction through a one-way mirror. Males reported experiencing more computer involvement than females. For males, past computer experience and masculinity were correlated with more positive computer attitude scores. For females, only past computer experience related to more positive computer attitude scores. Analyses of the computer interaction variable indicated that participants asked male research assistants significantly more questions than female research assistants. Several interaction effects were also found.A previous version of this paper was presented at the annual meeting of the Southwestern Psychological Association, New Orleans, April 1991.     

Parental self-esteem and behavior problems in children: Similarities between mothers and fathers

The relationship between parental self-esteem and behavior problems in children was investigated using 1624 married couple's responses from the National Survey of Families and Households. The sample was weighted to be nationally representative in terms of race and ethnicity. It was hypothesized that the existence of behavior problems among children would be associated with low self-esteem among parents and that the parent's gender, child's gender, parents' gender role attitudes, and parental employment would moderate this relationship. The results indicated that parental self-esteem is negatively associated with behavior problems in children. However, none of the moderating variables had a significant impact. This suggests that the relationship between parental self-esteem and behavior problems among children is robust and does not vary appreciably with the gender of the parent, the gender of the child, the attitudes of the parent, or the employment of the parent.     

The relationship between underpredicted pain and escape

Escape and avoidance that are disproportional to the danger of the pertinent stimulus are important clinical problems that are often related to inaccurate (catastrophic) expectations. One possible source of such expectations is a prior, underestimated aversive experience. In the present experiment the hypotheses that underestimated pain leads to escape and that it leads to avoidance were tested. In order to control for the effect of the intensity of the pain stimulus, a control group that received 20 pain stimuli of high intensity was formed. Subjects in the experimental condition received 17 pain stimuli of low intensity and 3 of (unexpectedly) high intensity (experimentally induced underprediction). Underprediction of the high intensity stimulus was significantly related to escape, but not to avoidance. The results suggest that the way in which avoidance was operationalized accounts for this. The strong support of the hypothesized relationship between underpredicted pain and escape is an important finding, however.     

Demonstrative utterances

Conclusion We have worked out a small part of a program originally devised by Kaplan which included a clarification of the phrase y intends to demonstrate x. The analysis of demonstrative utterances, combined with a theory of deferred ostensive reference, enabled us to account for a much larger class of utterances (accompained by a relevant gesture) than expected. Regrettably, the analysis forces more questions on us than it answers. Although I have used the term gesture quite freely without providing any sort of explication, there is much more to say about gestures and their relation to speech. Especially questions concerning the ontological nature of gestures (What kind of a thing is a gesture anyway?), their epistemological status (How can we tell gestures apart from other actions?), and their semantic status (What makes a gesture have meaning?) have remained largely unexplored. To my knowledge, no philosopher in the analytic tradition has addressed those issues in any systematic manner.