How Pseudo-hypotheses Defeat a Non-Bayesian Theory of Evidence: Reply to Bandyopadhyay,Taper, and Brittan

Bandyopadhyay, Taper, and Brittan (BTB) advance a measure of evidential support that first appeared in the statistical and philosophical literature four decades ago and have been extensively discussed since. I have argued elsewhere, however, that it is vulnerable to a simple counterexample. BTB claim that the counterexample is flawed because it conflates evidence with confirmation. In this reply, I argue that the counterexample stands, and is fatal to their theory.     

Structural analysis of the intension and extension of semantic concepts

The present studies examined the nature of visuo-spatial working memory development using conventional visual span and spatial span measures. Children aged between 6 and 13 years and adults aged 18-38 years were employed as participants. In Study 1, visual span, spatial span, articulation rate, and verbal fluency competencies were measured. In Study 2, visual span and spatial span maintenance was subject to five interference formats: nil, speech articulation, verbal fluency, visual masking, and spatial tapping. Distinct developmental rates were found for the two span tasks, which in the older children were correlated with the verbal fluency measure. Study 2 provided experimental evidence of the contribution of executive and spatial processes to spatial and to visual span maintenance. The results are interpreted as indicating that these memory span procedures make complex demands upon the visuo-spatial working memory architecture and consequently a precise identification of the process that actually develop is compromised. It is suggested that a componential approach where tasks are constructed to tap specific working memory components would afford a more accurate understanding of the development of these processes.     

Contributions of the nucleus accumbens and its subregions to different aspects of risk-based decision making

The nucleus accumbens (NAc) has been implicated in mediating different forms of decision making in humans and animals. In the present study, we observed that inactivation of the rat NAc, via infusion of GABA agonists, reduced preference for a large/risky option and increased response latencies on a probabilistic discounting task. Discrete inactivations of the NAc shell and core revealed further differences between these regions in mediating choice and response latencies, respectively. The effect on choice was attributable to reduced win–stay performance (i.e., choosing risky after a being rewarded for a risky choice on a preceding trial). Moreover, NAc inactivation altered choice only when the large/risky option had greater long-term value, in terms of the amount of food that could be obtained over multiple trials relative to the small/certain option. Inactivation of the NAc or the shell subregion also slightly reduced preference for larger rewards on a reward magnitude discrimination. Thus, the NAc seems to play a small role in biasing choice toward larger rewards, but its contribution to behavior is amplified when delivery of these rewards is uncertain, helping to direct response selection toward more favorable outcomes.     

Integration versus separation in Stroop‐like counting interference tasks1

Abstract: Two versions of a Stroop‐like counting interference task were compared to examine how irrelevant information is ignored. In the integrated task, participants enumerated digits (inconsistent condition) or letters (neutral condition) while attempting to ignore the identity of the characters. In the newly created separated task, participants enumerated asterisks while attempting to ignore a single digit (inconsistent condition) or letter (neutral condition) at fixation. Interference (longer responses in the inconsistent condition than in the neutral condition) was small but significant in both tasks but was not reduced by separation. Contrasted with the pattern in the color–word Stroop task, these results suggest that dimensional separation has different effects on interference depending on the overall amount of interference.     

Motivation and Management Styles in the Public and Private Sectors in Taiwan and a Comparison With the United States

Motivation studies in organizations have focused primarily on private sector organizations in the U.S. The current study looks at motivation and managerial styles in the private and public sectors in Taiwan (Republic of China). The results were also compared to nonnative data for the U.S. The findings indicate that motivational levels are much higher in Taiwan than in the U.S. and consistent between the public and private sectors. There is also a strong positive perception of public sector work in Taiwan and a greater understanding and commitment to participate in motivationally based managerial styles in all types of organizations. The study suggests the need to explore the motivational processes in organizations other than those based in the Western culture.     

A Positive Perspective on Attentional Bias: Positive Affectivity and Attentional Bias to Positive Information

In recent years there has been growing interest in determining the attentional basis of positive affectivity. Investigators have sought to evaluate the hypothesis that elevated positive affectivity is characterized by an attentional bias that favours the processing of positive information over neutral information. Unfortunately, in the studies carried out to date, the assessment procedures used by researchers to assess such attentional selectivity have either been methodologically limited or methodologically flawed. Hence, the validity of the hypothesis has remained indeterminate. To overcome the problems associated with attentional assessment procedures used in previous studies, and so shed light on the attentional basis of positive affectivity, we employed an appropriate variant of the attentional probe task. Our findings show that participants high in positive affectivity displayed greater relative attention to positive information compared to neutral information, than was the case for their low positive affectivity counterparts. Thus, the present results support the hypothesis that an attentional bias to positive information, relative to neutral information, is characteristic of elevated positive affectivity.