Decomposition of a Rasch partial credit item into independent binary and indecomposable trinary items

For each Rasch (Masters) partial credit item, there exists a set of independent Rasch binary and indecomposable trinary items for which the sum of the scores and the partial credit score have identical probability density functions. If each indecomposable trinary item is further expressed as the sum of two binary items, then the binary items are positively dependent and cannot be both of the Rasch type. This paper was written while the author was working with Steve Ferrara and Hillary Michaels on some technical aspects of the Maryland School Performance Assessment Program. The author had been puzzled by the fact that most MSPAP assessment items have three or less score categories. With a psychometric justification now being apparent, this paper is dedicated to both of them.     

Cross-cultural consistency of coding the strange situation

This study tested whether or not cross-cultural differences in attachment classification distributions result from systematic differences in coding practices. First, we investigated whether or not the interactive scales have been scored consistently in several different cross-cultural samples. Second, the Richters, Waters, and Vaughn (1988) functions were applied to address the question of whether or not attachment classifications were consistently based upon the same pattern of interactive behaviors. Third, cross-cultural coding differences were described from a multivariate perspective. Data sets from seven investigators in six countries were available for analysis. Analyses on this “multinational data set” revealed that except for distance interaction, the interactive scales in the two reunion episodes were scored in accordance with the original coding rules. Furthermore, a good to reasonable agreement appeared to exist between the original classifications and those computed by the functions, except for infants older than 20 months of age. The multivariate principal component analysis showed that classification groups across cultures were more alike than cultures across classification groups. Our data showed, therefore, that attachment classifications have been consistently coded across cultures.     

Choice: A local analysis

Analyses of free-operant choice usually employ one of two general procedures: the simple concurrent procedure (i.e., a concurrent variable-interval variable-interval schedule) or the concurrent-chains procedure (i.e., concurrently available initial links, each leading to an exclusively available terminal link). Theories about choice usually focus on only one of the two procedures. For example, maximization theories, which assert that behavior is distributed between two alternatives in such a way that overall rate of reinforcement is maximized, have been applied only to the simple concurrent procedure. In the present paper, a form of the pairing hypothesis (according to which pairings between one stimulus and another affect the value of the first, and pairings between responses and reinforcers affect the value of the former) is developed in a way that allows it to make qualitative predictions with regard to choice in a variety of simple concurrent and concurrent-chains procedures. The predictions include matching on concurrent variable-interval variable-interval schedules, preference reversal in the self-control paradigm, and preference for tandem over chained terminal links.     

Decision-making competence and cognitive abilities: Which abilities matter?

Decision-making competence is a skill that is associated with numerous positive life outcomes. Even though multiple cognitive abilities have been shown to predict decision-making competence, few studies have incorporated a large test battery tapping into several cognitive abilities concurrently in the same models. The current paper presents a study that sought to investigate which cognitive abilities predicted overall decision-making competence in adults using hierarchical regression analysis. A cognitive test battery, comprising abilities such as general intelligence, executive functions, numeracy, visuospatial ability, and time perception, was administered to 182 participants. Results indicate that both general intelligence, which was consistently the strongest predictor, and numeracy contributed independently to overall decision-making competence. Executive functions did predict overall decision-making competence, while all predictors were included in the models. A novel finding concerns the relationship between time perception and decision-making competence. The complementary roles of these cognitive abilities are discussed.     

Derived Trail Making Test indices: demographics and cognitive background variables across the adult life span

We examined the contribution of demographics and cognitive background variables (processing speed, visuospatial skill, working memory, and interference control) on derived Trail Making Test (TMT) scores in a large sample of Greek healthy participants. We included 775 participants and administered the TMT (TMT-A and TMT-B) and the Wechsler Intelligence Adult Scale (WAIS). Direct (TMT-A & TMT-B time-to-completion) and derived [difference TMT-(B ? A) & ratio TMT-(B/A)] scores were calculated. Demographics (age, age², education, and gender) and WAIS Full Intelligence Quotient significantly predicted the direct TMT-A (R² = 0.426) and TMT-B (R² = 0.593) scores and to a lesser extent, the derived TMT-(B ? A) (R² = 0.343) and TMT-(B/A) (R² = 0.088) scores. In a subsample of 537 healthy participants who also completed the Stroop Neuropsychological Screening Test (SNST), demographics (age and education), WAIS Digit Symbol, Block Design, Arithmetic, and SNST accounted for 44.8% and 59.7% of the variance on TMT-A and TMT-B, and 32.5% and 9.6% of the variance on TMT-(B ? A) and TMT-(B/A), respectively. We found minimal influence of Block Design and Arithmetic on TMT-(B ? A) and an absence of significant influence of any cognitive variable on TMT-(B/A) score. Concluding, derived TMT scores are suggested as indices to detect impairment in cognitive flexibility across the adult life span, since they minimize the effect of demographics and other cognitive background variables.     

White Matter Hyperintensities and Working Memory: An Explorative Study

ABSTRACT

White matter hyperintensities (WMH) are commonly observed in elderly people and may have the most profound effect on executive functions, including working memory. Surprisingly, the Digit Span backward, a frequently employed working memory task, reveals no association with WMH. In the present study, it was investigated whether more detailed analyses of WMH variables and study sample selection are important when establishing a possible relationship between the Digit Span backward and WMH. To accomplish this, the Digit Span backward and additional working memory tests, WMH subscores, and cardiovascular risk factors were examined. The results revealed that performance on the Digit Span backward test is unrelated to WMH, whereas a relationship between other working memory tests and WMH was confirmed. Furthermore, a division between several white matter regions seems important; hyperintensities in the frontal deep white matter regions were the strongest predictor of working memory performance.