The cognitive substrate of subjective probability

The prominent cognitive theories of probability judgment were primarily developed to explain cognitive biases rather than to account for the cognitive processes in probability judgment. In this article the authors compare 3 major theories of the processes and representations in probability judgment: the representativeness heuristic, implemented as prototype similarity, relative likelihood, or evidential support accumulation (ESAM; D. J. Koehler, C. M. White, & R. Grondin, 2003); cue-based relative frequency; and exemplar memory, implemented by probabilities from exemplars (PROBEX; P. Juslin & M. Persson, 2002). Three experiments with different task structures consistently demonstrate that exemplar memory is the best account of the data whereas the results are inconsistent with extant formulations of the representativeness heuristic and cue-based relative frequency.     

Sample size and the detection of correlation--a signal detection account: comment on Kareev (2000) and Juslin and Olsson (2005)

Simulations examined the hypothesis that small samples can provide better grounds for inferring the existence of a population correlation, p, than can large samples. Samples of 5, 7, 10, 15, or 30 data pairs were drawn either from a population with p=0 or from one with p>0. When decision accuracy was assessed independently for each level of the decision criterion, there was a criterion-specific small-sample advantage. For liberal criteria, accuracy was greater for large than for small samples, but for conservative criteria, the opposite result occurred. There was no small-sample advantage when accuracy was measured as the area under a receiver operating characteristic curve or as the posterior probability of a hit. The results show that small-sample advantages can occur, but under limited conditions.     

Lost in the wilderness: terror management, action orientation, and nature evaluation

The authors propose that wilderness is intrinsically associated with death, and, consequently, terror management concerns may promote more negative evaluations of wilderness. Consistent with this, wilderness inspired more thoughts about death than either cultivated nature or urban environments (Study 1), and death reminders reduced perceived beauty of wilderness (Study 2). The authors further suggest that active self-regulation facilitates suppression of the dark side of wilderness. Consistent with this, action orientation was positively related to perceived beauty of wilderness (Study 3), and after viewing wilderness, action-oriented individuals were more efficient at suppressing the association between wilderness and death than state-oriented individuals (Study 4). Direct death reminders overruled the effects of action orientation on nature evaluation (Study 5), presumably because direct death reminders are difficult to suppress even for action-oriented individuals.     

Using artificial life to teach evolutionary biology

This paper presents a pilot study on the use of artificial life software in an educational setting. Two groups of high school students received a standard lesson in evolutionary biology followed by a software session. The experimental group used the suite of artificial life software presented in this paper; the control group used a commercial multimedia hypertext. At the end of the software session both groups were asked to fill in a simple multiple-choice questionnaire testing the students knowledge of various aspects of evolutionary biology. The results show that the group using the artificial life software performed significantly better than the control group. We argue that the experimental group may learn more effectively because the artificial life makes it possible for students to perform experiments, a possibility not available to the control group.

An evaluation of the Tripartite Influence Model of body dissatisfaction and eating disturbance with adolescent girls

The Tripartite Influence Model of body image and eating disturbance proposes that three formative influences (peer, parents, and media) affect body image and eating problems through two mediational mechanisms: internalization of the thin-ideal and appearance comparison processes. The current study evaluated this model in a sample of 325 sixth through eighth grade girls. Simple path analyses indicated that internalization and comparison fully mediated the relationship between parental influence and body dissatisfaction and partially mediated the relationship between peer influence and body dissatisfaction. Additionally, internalization and comparison partially mediated the relationship between media influence and body dissatisfaction. Six a priori SEM models based on the full Tripartite Influence Model were also evaluated. A resulting model was found to be an adequate fit to the data, supporting the viability of the Tripartite Model as a useful framework for understanding processes that may predispose young women to develop body image disturbances and eating dysfunction.     

Quantitative genetic analysis of latent growth curve models of cognitive abilities in adulthood

Though many cognitive abilities exhibit marked decline over the adult years, individual differences in rates of change have been observed. In the current study, biometrical latent growth models were used to examine sources of variability for ability level (intercept) and change (linear and quadratic effects) for verbal, fluid, memory, and perceptual speed abilities in the Swedish Adoption/Twin Study of Aging. Genetic influences were more important for ability level at age 65 and quadratic change than for linear slope at age 65. Expected variance components indicated decreasing genetic and increasing nonshared environmental variation over age. Exceptions included one verbal and two memory measures that showed increasing genetic and nonshared environmental variance. The present findings provide support for theories of the increasing influence of the environment with age on cognitive abilities.     

Depression and vulnerability as assessed by the Rorschach method

We examined clinically depressed (CD; n = 16), previously depressed (PD; n = 19) and never depressed (ND; n = 18) individuals on 13 theoretically selected Rorschach (Exner, 1993; Rorschach, 1942) variables and on the Beck Depression Inventory (BDI; Beck, Rush, Shaw, & Emery, 1979). The group assignment was made according to the criteria of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994). We tested 2 contradictory models for depressive vulnerability, Beck's (Clark & Beck, 1999) and Miranda and Persons's (1988; Persons & Miranda, 1992), in a planned comparison design with focused contrasts. The CDs significantly contrasted the combined group of NDs and the PDs in a pathological direction on 8 of the 13 Rorschach variables and on the BDI. However, the combined group of CDs and PDs also significantly contrasted the NDs in a pathological direction on 3 of these Rorschach variables and on the BDI. In addition, logistic regression analyses indicated that Rorschach indexes significantly improved the prediction of major depression above and beyond that achieved by the BDI. The findings show that the Rorschach method was able to identify (a) cognitive and aggressive disturbances that are present in individuals who are actively depressed but not in individuals who have been depressed in the past or never been depressed and (b) affective and coping disturbances that are present in depressed individuals and to some degree in PD individuals but not in individuals who have not experienced depression. We discuss the scanty evidence of psychological disturbances in PD individuals, as measured with the Rorschach, in relation to the mood-state dependent hypothesis of Miranda and Persons (1988; Persons & Miranda, 1992).