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161.
Little research has been carried out on human performance in optimization problems, such as the Traveling Salesman problem
(TSP). Studies by Polivanova (1974, Voprosy Psikhologii, 4, 41–51) and by MacGregor and Ormerod (1996, Perception & Psychophysics, 58, 527–539) suggest that: (1) the complexity of solutions to visually presented TSPs depends on the number of points on the
convex hull; and (2) the perception of optimal structure is an innate tendency of the visual system, not subject to individual
differences. Results are reported from two experiments. In the first, measures of the total length and completion speed of
pathways, and a measure of path uncertainty were compared with optimal solutions produced by an elastic net algorithm and
by several heuristic methods. Performance was also compared under instructions to draw the shortest or the most attractive
pathway. In the second, various measures of performance were compared with scores on Raven's advanced progressive matrices
(APM). The number of points on the convex hull did not determine the relative optimality of solutions, although both this
factor and the total number of points influenced solution speed and path uncertainty. Subjects' solutions showed appreciable
individual differences, which had a strong correlation with APM scores. The relation between perceptual organization and the
process of solving visually presented TSPs is briefly discussed, as is the potential of optimization for providing a conceptual
framework for the study of intelligence.
Received: 28 December 1998 / Accepted: 20 January 2000 相似文献
162.
Kissell JL 《Theoretical medicine and bioethics》2001,22(1):1-4
Theoretical Medicine and Bioethics - 相似文献
163.
This study examined 2-point discrimination performance in 1 st-degree biological relatives (n = 39) of individuals with schizophrenia and normal adult control participants (n = 30) recruited from the community. They completed an objective 2-point discrimination task, adapted for use with a signal detection approach to permit separation of discriminability (i.e., sensitivity, d') from response bias/ criterion (or motivation, lnbeta). Relatives revealed poorer performance on the d' index compared with controls. The 2 groups did not differ on lnbeta, suggesting a genuine difference in sensitivity but not response bias. The sensitivity deficit might reflect decreased spatial acuity and/or impaired intensity cue processing of tactile stimuli. Poor performance on the d' index was most closely associated with 2 schizotypic features, namely "odd beliefs/magical thinking." 相似文献
164.
During summer, female meadow voles (Microtus pennsylvanicus) maintain territories and males do not engage in paternal care. As day length shortens, territories dissolve and males nest with females and young. Because paternal behavior has never been studied in free-living meadow voles during colder months or in the laboratory under short photoperiods, the authors examined whether males housed in short day (SD) lengths exhibited more frequent or better quality paternal behavior than males housed in long day (LD) lengths. Sexually and parentally inexperienced (naive) SD males exhibited proportionally more and qualitatively better paternal care than naive LD males. SD males were more responsive than LD males to classic social cues associated with prepartum aggression inhibition and paternal onset. SD sires also displayed qualitatively better paternal behavior than LD sires. These data suggest that meadow vole paternal state is regulated by specific social and environmental cues that may contain reliable information about ecological conditions that favor paternal care. 相似文献
165.
Making external attributions for negative events, though often considered “self-serving,” also implies that the attributor is not in control of critical resources. We hypothesized that making external attributions for negative events will lead to impressions of powerlessness. Because individuals in high-status roles are expected to have power and control, external attributions may violate these role expectations; thus, we further hypothesized that status would moderate the relationship between attributions and interpersonal outcomes. Specifically, more negative impressions and affect will be directed toward high-status individuals who make external attributions than toward their lower status counterparts. Three studies were conducted, one using a role-play methodology, one using an experimentally created hierarchy, and one using vignettes. The results supported our hypotheses: external attributions can be highly disserving for people in high-status positions. 相似文献
166.
The authors compared levels of optimistic and pessimistic bias in the prediction of positive and negative life events between European Americans and Japanese. Study 1 showed that European Americans compared with Japanese were more likely to predict positive events to occur to self than to others. The opposite pattern emerged in the prediction of negative events. Study 2 replicated these cultural differences. Furthermore, positive associations emerged between predictions and occurrence of life events 2 months later for both European Americans and Japanese. Across both studies, results of within-groups analyses indicated that both groups expected negative events to be more likely to occur to others than to self (optimistic bias). In addition, Japanese expected positive events to be more likely to occur to others than to self (pessimistic bias). However, European Americans failed to show the expected optimistic bias for positive events. 相似文献
167.
Lee A. Kirkpatrick 《Journal of personality》1999,67(2):245-258
Buss and Greiling cite individual differences in attachment as a principal illustration of adaptive individual differences. This particular example, however, is a highly controversial one: Many if not most relationship researchers assume (implicitly or explicitly) that insecure attachment patterns reflect some kind of malfunction of the attachment system in modern environments rather than evolved facultative strategies. I therefore review some of the arguments and evidence on both sides of this issue, along with the closely related topics of mating/reproductive strategies and parental investment. In the end I support the Buss-Greiling position, but for reasons not discussed in their article. 相似文献
168.
169.
170.
Green and Salovey agree with us that happiness and sadness are strongly bipolar, and that Positive and Negative Activation are not. However, Green and Salovey subscribe to the two-dimensional circumplex, a model we find wanting. Actually, the problems they discuss arise from the limitations of the circumplex rather than from issues fundamental to affective structure. And they do not consider the evidence, reported in our target article, that supports an alternative to the circumplex: a three-level hierarchical model. In this reply, we take a closer look at the empirical findings supporting this model, and we emphasize its heuristic promise. 相似文献