Subjects' inferential performance and the interaction of data and hypotheses in probabilistic inference tasks

In a recent paper, Knez (1991) showed an interaction of data and hypotheses in probabilistic inference tasks. The results illustrated two, earlier not obtained, significant main effects on subjects' hypothesis sampling , viz. the effect of different forms of data presentation and subjects' execution of cognitive control over their hypothesis pool throughout the series of trials. The present paper followed up these results in that the subjects' hypothesis testing , in Knez (1991) was subjected to an analysis. Hence, to see if the effects mentioned above significantly influenced the subjects' hypothesis testing, as they did for subjects' hypothesis sampling. The results showed a consistency with Knez (1991), i.e. the results emphasize the interaction of data and hypothesis in probabilistic inference tasks, as well as the subjects' execution of cognitive control over their hypothesis pool concerning both the subjects' hypothesis sampling and testing.     

The choice of constraints in correspondence analysis

A discussion of alternative constraint systems has been lacking in the literature on correspondence analysis and related techniques. This paper reiterates earlier results that an explicit choice of constraints has to be made which can have important effects on the resulting scores. The paper also presents new results on dealing with missing data and probabilistic category assignment.I am most grateful to the following for their helpful comments. Arto Demirjian, Michael Greenacre, Michael Healy, Shizuhiko Nishisato, Roderick Mcdonald, and several anonymous referees.     

Development of Standard Anchors for Scoring Generic Past-Behaviour Questions in Structured Interviews

A structured interviewing system was developed which included an item bank of pre-written past-behaviour questions. Scoring anchors for each of 168 questions in the item bank were created from analysis of protocols from individual assessments. A concurrent validation study was conducted, focusing on the job of highway patrol sergeant. Job knowledge experts used a job analysis tool to select a subset of twelve questions from the item bank. Panel interviews were conducted with 32 highway patrol sergeants as subjects. Average inter-rater reliability was 0.65 and interview validity was 0.42 for group consensus scores and 0.44 for panel average scores. Discussion focused on practical issues affecting the interviewing system.     

Isotonic ordinal probabilistic models (ISOP)

The concept of an ordinal instrumental probabilistic comparison is introduced. It relies on an ordinal scale given a priori and on the concept of stochastic dominance. It is used to define a weakly independently ordered system, or isotonic ordinal probabilistic (ISOP) model, which allows the construction of separate sample-free ordinal scales on a set of subjects and a set of items. The ISOP-model is a common nonparametric theoretical structure for unidimensional models for quantitative, ordinal and dichotomous variables.Fundamental theorems on dichotomous and polytomous weakly independently ordered systems are derived. It is shown that the raw score system has the same formal properties as the latent system, and therefore the latter can be tested at the observed empirical level.I wish to thank 3 reviewers and 2 editors who contributed a lot to the readability and precision of the article.     

A probabilistic multidimensional scaling with unique axes1

Abstract: A probabilistic multidimensional scaling model is proposed. The model assumes that the coordinates of each stimulus are normally distributed with variance Σ_i = diag(σ²₁, … σ²_Ri). The advantage of this model is that axes are determined uniquely. The distribution of the distance between two stimuli is obtained by polar coordinates transformation. The method of maximum likelihood estimation for means and variances using the EM algorithm is discussed. Further, simulated annealing is suggested as a means of obtaining initial values in order to avoid local maxima. A simulation study shows that the estimates are accurate, and a numerical example concerning the location of Japanese cities shows that natural axes can be obtained without introducing individual parameters.     

Classical Non-Associative Lambek Calculus

We introduce non-associative linear logic, which may be seen as the classical version of the non-associative Lambek calculus. We define its sequent calculus, its theory of proof-nets, for which we give a correctness criterion and a sequentialization theorem, and we show proof search in it is polynomial.     

Delusion‐proneness or miscomprehension? A re‐examination of the jumping‐to‐conclusions bias

Previous research has consistently shown that individuals with delusions typically exhibit a jumping‐to‐conclusions (JTC) bias when administrated the probabilistic reasoning ‘beads task’ (i.e., decisions made on limited evidence and/or decisions over‐adjusted in light of disconfirming evidence). However, recent work in this area has indicated that a lack of comprehension of the task may be confounding this finding. The purpose of the present study was to evaluate the influence of task administration, delusion‐proneness, and miscomprehension on the elucidation of the JTC bias. A total of 92 undergraduate university students were divided into one of two task conditions (i.e., non‐computerised and computerised) and were further identified as either delusion‐prone or non‐delusion‐prone and as comprehending or non‐comprehending the task. Overall, 25% of the sample demonstrated a JTC bias, and just over half made illogical responses consistent with a failure to comprehend the task. Qualitative evidence of comprehension revealed that these ‘illogical responses’ were being driven by a misunderstanding of task instructions. The way the task was administrated and levels of delusion‐proneness did not significantly influence JTC. However, miscomprehending participants were significantly more likely to exhibit the bias than those who did comprehend. These results suggest that miscomprehension rather than delusion‐proneness may be driving the JTC bias, and that future research should include measures of miscomprehension.     

Patterns of Responding on a Balloon Analogue Task Reveal Individual Differences in Overall Risk-Taking: Choice Between Guaranteed and Uncertain Cash

ABSTRACT. We explored the utility of analyzing within- and between-balloon response patterns on a balloon analogue task (BAT) in relation to overall risk scores, and to a choice between a small guaranteed cash reward and an uncertain reward of the same expected value. Young adults (n = 61) played a BAT, and then were offered a choice between $5 in cash and betting to win $0 to $15. Between groups, pumping was differentially influenced by explosions and by the number of successive unexploded balloons, with risk takers responding increasingly on successive balloons after an explosion. Within-balloons, risk takers showed a characteristic pattern of constant high rate, while non-risk takers showed a characteristic variable lower rate. Overall, results show that the higher number of pumps and explosions that characterize risk takers at a molar level, result from particular forms of adaptation to the positive and negative outcomes of choices seen at a molecular level.

Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/vgen.     

Imminent Danger? Probabilistic Classification Learning of Threat-Related Information in Obsessive-Compulsive Disorder

A tendency to overestimate threat has been shown in individuals with OCD. We tested the hypothesis that this bias in judgment is related to difficulties in learning probabilistic associations between events. Thirty participants with OCD and 30 matched healthy controls completed a learning experiment involving 2 variants of a probabilistic classification learning task. In the neutral weather-prediction task, rainy and sunny weather had to be predicted. In the emotional task danger of an epidemic from virus infection had to be predicted (epidemic-prediction task). Participants with OCD were as able as controls to improve their prediction of neutral events across learning trials but scored significantly below healthy controls on the epidemic-prediction task. Lower performance on the emotional task variant was significantly related to a heightened tendency to overestimate threat. Biased information processing in OCD might thus hamper corrective experiences regarding the probability of threatening events.