Beta-MPT: Multinomial processing tree models for addressing individual differences

Traditionally, multinomial processing tree (MPT) models are applied to groups of homogeneous participants, where all participants within a group are assumed to have identical MPT model parameter values. This assumption is unreasonable when MPT models are used for clinical assessment, and it often may be suspect for applications to ordinary psychological experiments. One method for dealing with parameter variability is to incorporate random effects assumptions into a model. This is achieved by assuming that participants’ parameters are drawn independently from some specified multivariate hyperdistribution. In this paper we explore the assumption that the hyperdistribution consists of independent beta distributions, one for each MPT model parameter. These beta-MPT models are ‘hierarchical models’, and their statistical inference is different from the usual approaches based on data aggregated over participants. The paper provides both classical (frequentist) and hierarchical Bayesian approaches to statistical inference for beta-MPT models. In simple cases the likelihood function can be obtained analytically; however, for more complex cases, Markov Chain Monte Carlo algorithms are constructed to assist both approaches to inference. Examples based on clinical assessment studies are provided to demonstrate the advantages of hierarchical MPT models over aggregate analysis in the presence of individual differences.     

Strategic grouping in the spatial span memory task

Spatial short-term memory performance was examined in relation to participants’ strategies. A total of 20 adult participants viewed and reproduced sequences of locations that varied in length (five, six, seven, or eight locations) and spatial separability (a manipulation of the configurations). In trial-by-trial self-reports, participants described five types of strategies. Chunking the spatial sequences into groups of three or four locations was the sole strategy associated with increased accuracy. Participants demonstrated considerable variability in the strategies that they selected, suggesting that cognitive resources are allocated to strategy selection, execution, and monitoring in the spatial span task. Spatially separable sequences were more accurately recalled than nonseparable sequences, independent of strategic grouping, suggesting two levels of grouping in the spatial span task.     

The role of working memory capacity in autobiographical retrieval: Individual differences in strategic search

Remembering previous experiences from one's personal past is a principal component of psychological well-being, personality, sense of self, decision making, and planning for the future. In the current study the ability to search for autobiographical information in memory was examined by having college students recall their Facebook friends. Individual differences in working memory capacity manifested itself in the search of autobiographical memory by way of the total number of friends remembered, the number of clusters of friends, size of clusters, and the speed with which participants could output their friends' names. Although working memory capacity was related to the ability to search autobiographical memory, participants did not differ in the manner in which they approached the search and used contextual cues to help query their memories. These results corroborate recent theorising, which suggests that working memory is a necessary component of self-generating contextual cues to strategically search memory for autobiographical information.     

The Developmental Activities of Elite Ice Hockey Players

The purpose of this study was to analyze the development of four 20 year-old elite hockey players through an in-depth examination of their sporting activities. The theoretical frameworkof deliberate practice (Ericsson, Krampe, & Tesch-Romer, 1993) and the notion of deliberate play (Côté, 1999) served as the theoretical foundations. Interviews were conducted to providea longitudinal and detailed account of each participant.s involvement in various sporting activities. The interviewer asked questions about the conditions and sporting activities for eachyear of development. The data obtained were validated through independent interviews conducted with three parents of three different athletes. The results were consistent with Côté.s(1999) three stages of development in sport: the sampling (age 6.12), specializing (age 13. 15), and investment (age 16+) years.     

Numerical approximation abilities correlate with and predict informal but not formal mathematics abilities

Previous research has found a relationship between individual differences in children’s precision when nonverbally approximating quantities and their school mathematics performance. School mathematics performance emerges from both informal (e.g., counting) and formal (e.g., knowledge of mathematics facts) abilities. It remains unknown whether approximation precision relates to both of these types of mathematics abilities. In the current study, we assessed the precision of numerical approximation in 85 3- to 7-year-old children four times over a span of 2 years. In addition, at the final time point, we tested children’s informal and formal mathematics abilities using the Test of Early Mathematics Ability (TEMA-3). We found that children’s numerical approximation precision correlated with and predicted their informal, but not formal, mathematics abilities when controlling for age and IQ. These results add to our growing understanding of the relationship between an unlearned nonsymbolic system of quantity representation and the system of mathematics reasoning that children come to master through instruction.     

How Do Romantic Relationship Satisfaction,Gender Stereotypes,and Gender Relate to Future Time Orientation in Romantic Relationships?

The present study is an investigation into how romantic relationship satisfaction and attitudes toward gender stereotypes about romantic relationship and gender are related to future time orientation in romantic relationships (FTORR). Four hundred and thirteen (208 men and 205 women) university students taking elective psychology courses at Middle East Technical University were given a scale including items about FTORR, romantic relationship satisfaction, and attitudes toward gender stereotypes about romantic relationships. All the participants were then involved in a heterosexual romantic relationship. Multiple regression results showed that for the women, attitudes toward men's assertiveness and men's dominance in relationships were more important predictors of FTORR than relationship satisfaction. For the men, attitudes toward men's assertiveness and romantic relationship satisfaction were important predictors of FTORR, but attitude toward men's dominance was not a predictor of FTORR. Women were more future oriented in their ongoing romantic relationships than were men. Finally, participants who were highly satisfied with their relationships scored higher on FTORR than those who were less satisfied.     

Perceived threat of infectious disease and its implications for sexual attitudes

A study (n = 411) investigated the relationship between chronic individual differences in germ aversion and sociosexual attitudes (short-term mating orientation, long-term mating orientation, and anticipated future sexual promiscuity), and also tested whether the magnitudes of these relations differ depending on the temporary perceptual salience of disease threat. Results revealed person-by-situation interactions. When the threat of disease was temporarily salient, germ aversion correlated negatively with short-term mating orientation and with future sexual promiscuity, and correlated positively with long-term mating orientation; these effects were either weaker or nonexistent under control conditions. These effects emerged most clearly among women.     

Examining the contextual and temporal stability of perceptions of emotional utility

The present research examined the degree to which perceptions of emotional utility are stable across contexts and over time. Self-reported perceptions of emotional utility and actual experience of emotion were measured in two samples of college students. In Study 1, participants were presented with two different types of goals (independent vs. interdependent) and were asked to rate the degree to which they found different types of emotions (e.g., appreciation, pride) useful in each context. In Study 2, participants completed daily online questionnaires in which they responded to questions assessing perceptions of emotional utility and actual affect in relation to personal goals. As predicted, across both samples, perceived utility of specific types of emotions was found to be associated with specific types of goals. Importantly, perceived utility of emotion was also found to be a relatively stable individual difference variable, even after taking into account the actual experience of emotion.     

Motivational pathways to STEM career choices: Using expectancy–value perspective to understand individual and gender differences in STEM fields

The United States has made a significant effort and investment in STEM education, yet the size and the composition of the STEM workforce continues to fail to meet demand. It is thus important to understand the barriers and factors that influence individual educational and career choices. In this article, we conduct a literature review of the current knowledge surrounding individual and gender differences in STEM educational and career choices, using expectancy–value theory as a guiding framework. The overarching goal of this paper is to provide both a well-defined theoretical framework and complementary empirical evidence for linking specific sociocultural, contextual, biological, and psychological factors to individual and gender differences in STEM interests and choices. Knowledge gained through this review will eventually guide future research and interventions designed to enhance individual motivation and capacity to pursue STEM careers, particularly for females who are interested in STEM but may be constrained by misinformation or stereotypes.