A binomial test for hierarchical dependency

A binomial test for hierarchical dependency is presented. The null hypothesis is that all members of a population who possess a certain skill are a subset of the members who possess another skill. This hypothesis is basic to the writings of several prominent theorists, such as Gagné and Piaget. The model, assumptions, formula derivations, and procedures for the test are explained. An illustrative example is also provided.     

Visual search,complex backgrounds,mental counters,and eye movements

For 30 days, three Ss searched for 1, 5, or 10 targets (N), any one of which had to occur once (as in past research). twice, or four times (FREQ). The N=1 and N=5 items were subsets of N=10 items. When FREQ=1. Ss searched longer for 5 targets than for 1 or 10 targets. This nonintuitive result was due to (a) Ss searching for all 10 targets even at N=5, and (b) the reported “pop-out effect” of the 5 target items as well as the other 5 items in the N=10 set. When FREQ > 1, Ss could search for only 2-3 targets at once, because they could not keep mental counters on more items. The presence of a complex background merely added a constant to search time. The main change in eye movements, with 30 days practice, was to reduce greatly the number of eye fixations, thus suggesting an increase in the useful fidld of view and/or a change in search strategy. A speculative model, based upon two comparison processes, was suggested to explain the results.     

An automated version of the digit symbol substitution test (DSST)

An automated version of the Digit Symbol Substitution Test is described that employs a relatively inexpensive, commercially available microcomputer to present and score the task. Advantages of the automated DSST include: (1) objective scoring of both speed and accuracy of test performance, (2) printed copies of test scores, (3) convenient administration under standardized test conditions, and (4) the capacity for repeated assessment of an individual’s performance over time. Task performance data for individual subjects following doses of pentobarbital are presented; these data illustrate both the stability of task performance under constant conditions and the within-subjects sensitivity of task performance to experimental manipulations.     

Secondary school curriculum and career behavior in young adults

As part of a larger longitudinal study of the effects of secondary school characteristics on career behavior in young adulthood, this paper presents findings obtained from 1007 males and females who graduated from high school in academic or vocational curricula 6 or 8 years ago. Criterion behavior included the completion of career development tasks in the exploration and establishment life stages as measured by the Adult Form of the Career Development Inventory, certainty about immediate occupational plans, and satisfaction with occupational goals and progress toward meeting them. Significant differences were found in the pattern of career development by curriculum but not by sex, in certainty by curriculum and sex, and in satisfaction by neither curriculum nor sex. The implications for a stage theory of career development are discussed.     

Essai sur la logique de l'indeterminisme et la ramification de l'espace-temps

Sans résumé     

Subjective hardness of compliant materials

The apparent hardness and softness of nine samples of compliant materials were scaled by direct magnitude estimation and by cross-modal matches to the apparent force exerted on a hand dynamometer and a finger dynamometer, and to the loudness of a band of white noise. The physical hardness (force/indentation) of the compliant specimens covered a range of more than 100 to 1, extending from a fairly soft sponge to a fairly hard block of rubber. The apparent hardness of the specimens was found to follow the psychophysical power law. Subjective hardness grows as the physical hardness raised to a power. The indicated exponent was about 0.8 for magnitude estimation, about 0.7 derived by calculation from handgrip matches, and about 0.6 derived by calculation from loudness matches.

Numerical estimates and cross-modal matches for softness gave functions that were approximately the reciprocal of the functions given for hardness. Hardness is a continuum on which there exists an upper threshold.