TRACX: a recognition-based connectionist framework for sequence segmentation and chunk extraction

Individuals of all ages extract structure from the sequences of patterns they encounter in their environment, an ability that is at the very heart of cognition. Exactly what underlies this ability has been the subject of much debate over the years. A novel mechanism, implicit chunk recognition (ICR), is proposed for sequence segmentation and chunk extraction. The mechanism relies on the recognition of previously encountered subsequences (chunks) in the input rather than on the prediction of upcoming items in the input sequence. A connectionist autoassociator model of ICR, truncated recursive autoassociative chunk extractor (TRACX), is presented in which chunks are extracted by means of truncated recursion. The performance and robustness of the model is demonstrated in a series of 9 simulations of empirical data, covering a wide range of phenomena from the infant statistical learning and adult implicit learning literatures, as well as 2 simulations demonstrating the model's ability to generalize to new input and to develop internal representations whose structure reflects that of the items in the input sequence. TRACX outperforms PARSER (Perruchet & Vintner, 1998) and the simple recurrent network (SRN, Cleeremans & McClelland, 1991) in matching human sequence segmentation on existing data. A new study is presented exploring 8-month-olds' use of backward transitional probabilities to segment auditory sequences.     

Testing mixture models of transitive preference: comment on Regenwetter, Dana, and Davis-Stober (2011)

This article contrasts 2 approaches to analyzing transitivity of preference and other behavioral properties in choice data. The approach of Regenwetter, Dana, and Davis-Stober (see record 2011-00732-003) assumes that on each choice, a decision maker samples randomly from a mixture of preference orders to determine whether A is preferred to B. In contrast, Birnbaum and Gutierrez (2007) assumed that within each block of trials, the decision maker has a true set of preferences and that random errors generate variability of response. In this latter approach, preferences are allowed to differ between people; within-person, they might differ between repetition blocks. Both approaches allow mixtures of preferences, both assume a type of independence, and both yield statistical tests. They differ with respect to the locus of independence in the data. The approaches also differ in the criterion for assessing the success of the models. Regenwetter et al. fitted only marginal choice proportions and assumed that choices are independent, which means that a mixture cannot be identified from the data. Birnbaum and Gutierrez fitted choice combinations with replications; their approach allows estimation of the probabilities in the mixture. It is suggested that researchers should separate tests of the stochastic model from the test of transitivity. Evidence testing independence and stationarity assumptions is presented. Available data appear to fit the assumption that errors are independent better than they fit the assumption that choices are independent.     

Evaluating a brief measure of social self-efficacy among U.S. adolescents

Preliminary data were collected to evaluate the performance of a social self-efficacy measure among 4,061 public high school adolescents. Principal-axis factor analysis was followed by a 4-way between-groups analysis of variance (ANOVA) to test for differences in the Total score means on selected demographic estimates and their interactions. Relations between the Total score and selected risk behaviors were examined through a series of one-way ANOVAs and the Tukey HSD test. Factor analysis results suggested a one-factor model best explained the factor structure of the scale items (factor loading range = .64 - .77, eigenvalue = 4.05, h(2) = .51). Females reported a significantly higher mean Total social self-efficacy rating than males, while White students reported a significantly higher mean Total social self-efficacy rating than Black and Asian students. Statistically significant lower mean Total social self-efficacy ratings were also noted for those who reported physical fighting, avoiding school, and being bullied.     

Academic decision making and prospect theory

Two studies are reported that investigate the applicability of prospect theory to college students' academic decision making. Exp. 1 failed to provide support for the risk-seeking portion of the fourfold pattern predicted by prospect theory but did find the greater weighting of losses over gains. Using a more sensitive dependent measure, in Exp. 2 the results of the first experiment were replicated in terms of the gain-loss effect and also found some support for the fourfold pattern in the interaction between probabilities and gain versus loss. The greatest risk-seeking was found in the high probability loss condition.     

Meehl's "crud" factor, subjective wellbeing, and religiosity: a critique'

Researchers in the area of subjective wellbeing are now building on a body of research that spans more than three decades and includes many thousands of articles. It is time to move from exploratory studies to those based on accumulated psychometric understanding and theory. Two aspects of the article by Abdel-Khalek (2011) warrant attention from this perspective: the choice of scale and the issue of shared variance.     

Development of the Mental Clutter Scale

Mental fog is a core symptom of fibromyalgia. Its definition and measurement are central to an understanding of fibromyalgia-related cognitive disability. The Mental Clutter Scale was designed to measure mental fogginess. In an exploratory factor analysis of two different samples (n=128 and n=170), cognitive symptoms of fibromyalgia loaded on 2 dimensions: cognition and mental clarity. The mental clarity factor comprised 8 items with factor loadings greater than .60 and was named the Mental Clutter Scale. The factor stability of the new scale was good, internal consistency was .95, and test-retest reliability over a median of 5 days was .92. The 8-item scale is a quick measure of mental fog that provides clinicians with information about cognitive functioning in fibromyalgia.     

Multiple group membership influences face-recognition: Recall and neurological evidence

The limited face-recognition research involving targets categorizable on multiple dimensions has provided contradictory evidence as to how partial-ingroup members are processed and recognized. This research demonstrates that partial-ingroup members are recognized in a manner distinct from double-ingroup and double-outgroup targets. Specifically, when race and university-affiliation are crossed, university-affiliation does not influence recognition for own-race targets, but does for other-race targets, in that other-race/own-university targets are recalled more accurately than other-race/other-university targets. The neurological mechanisms involved in the effect are explored through the inclusion of electroencephalography.     

Seeing isn't believing: the effect of intergroup exposure on children's essentialist beliefs about ethnic categories

Adults and children seem to essentialize certain social categories. Three studies investigated whether, and how, exposure to ethnic diversity affects this bias. Participants were 516 kindergarten, 2nd grade, and 6th grade Israeli Jewish and Arab children attending regular (mono-cultural) or integrated schools. Study 1 revealed that exposure increased the salience of ethnicity, especially for Jewish children. Study 2 showed no differences among groups at kindergarten regarding the relevance of recalling a story character's ethnicity, but by 2nd grade, Jewish children attending integrated schools were the most likely to mention such information. Finally, Study 3 revealed that while all kindergarteners started off at a similar level of essentialism towards ethnicity, exposure affected Arab, but especially Jewish, children's essentialist beliefs. Moreover, there were negative correlations between the salience of and essentialism towards ethnicity. Thus, interethnic exposure alleviated children's essentialist bias towards ethnicity and did so via making children aware of, rather than blind to, ethnic categories.     

Cross-cultural differences in the refusal to accept a small gift: the differential influence of reciprocity norms on Asians and North Americans

Asians are more likely than North Americans to refuse a small gift that is offered to them by a casual acquaintance. Five experiments confirmed this difference and explored the reasons for its occurrence. Asians, who are inclined to think of themselves in relation to others, are more likely than North Americans to invoke a reciprocity norm in exchanging gifts with casual acquaintances, and they refuse a gift in order to avoid the feeling of indebtedness they would experience if they cannot reciprocate. North Americans, however, who are inclined to think of themselves independently of others, are more likely to base their acceptance of the gift on its attractiveness without considering their obligation to reciprocate. These cultural differences are not evident when the gift is offered by a close friend with whom individuals have a communal relationship. Implications of our findings for miscommunication between members of different cultures are discussed.