Visual discrimination between rectangular and nonrectangular parallelopipeds

Twenty-seven university students judged whether each of 128 drawings of parallelopipeds appeared to represent three-dimensional rectangular boxes. Half the pictures could not geometrically have been projections of rectangular boxes. The null hypothesis that Ss’ judgments were unrelated to geometry was rejected at the .001 level of significance, and the correlation between Ss’ judgments and perfect discrimination averaged .86 over three variations of the experiment. The results support a general hypothesis about the perception of simple space forms according to which viewers impose geometric constraints, such as rectangularity and symmetry, but only when the constraints are projectively possible.     

Averaging: An empirical validity criterion for magnitude estimation

Ss judged grayness of neutral value Munsell chips under two response conditions: magnitude estimation and graphic rating. In addition, they judged average grayness of pairs of chips under the same two response modes. The averaging data were evaluated in terms of a simple model for subjective averaging. The graphic rating data fitted the model, but the magnitude estimates showed consistent discrepancy. It was concluded that the Ss were averaging, but that magnitude estimation distorted their judgments.     

Sleep and overextinction of the GSR component of the orienting response

Overextinction of the GSR component of the orienting response was examined in a sample of 68 socially disturbed adolescents. Continued stimulus repetition beyond the point of habituation resulted in GSR return after 50–60 stimulus presentations. However, division of Ss into sleep and non-sleep groups using behavioral and self-report criteria, failed to support Sokolov’s (1963) notion that overextinction is accompanied by drowsiness. A possible explanation of these results is discussed.     

The asymptotic distribution of response probabilities in the Audley-Jonckheere learning model

The asymptotic distributions of response probabilities in the Audley-Jonckheere learning model, as applied to the two-choice learning situation, are described for (1) the experimenter-controlled events model, (2) the subject-controlled events model, and (3) the experimenter-subject-controlled events model.     

An electronic audio switch

This article describes an electronic switch that allows presentation of sine wave stimuli without the often undesirable transient thump, thud, or click usually caused by ordinary electromechanical switches.     

An electronic aid for presenting equivalent information in concept identification

An electronic aid to assist in administering concept-identification problems with floating solutions is described. Digital circuitry generates all combination pairs from four selection switches, presents a particular comparison of these pairs, and, on command of the E, eliminates selected pairs from future comparisons. Each comparison is designed to minimize the information fed back to the S. The apparatus is used to administer and evaluate performance on conjunctive and disjunctive problems that are matched for information gain.     

Recognition assessed by D' and by a non-parametric alternative (the A-index) as a function of the number of choices

Freedom from restrictive assumptions and ease of psychological interpretation are two basic criteria for a satisfactory measure of recognition performance. The A-index (Brown, 1965a) comes close to fulfilling these criteria. It is based on the proportion of wrong choices rejected in a multi-choice test as revealed by the number of choices required to select the correct choice. It can be transformed into the d' measure of signal detection theory (SDT) if the standard assumptions of this theory hold, but not in general. Two experiments on the recognition of words-in-noise are described. In the first there were 3, 5, 8 or 16 choices. They were typed on a card which was displayed to the listener during the presentation of a word. On both measures 5-, 8- and 16-choice recognition did not differ significantly, while 3-choice recognition was slightly, but significantly, superior. The second experiment concerned the effect of delaying the display of the card until 2 sec. after presentation. No evidence for an effect was obtained. In both experiments, there was suggestive but not conclusive evidence that the d' measure tended to overestimate recognition efficiency.     

USE OF THE GATB IN PREDICTING SUCCESS ON THE TESTS OF GENERAL EDUCATIONAL DEVELOPMENT

An attempt was made to determine how useful the General Aptitude Test Battery can be when used as a predictor of success on the Tests of General Educational Development. The General Ability and Verbal Aptitude subtests of the GATB were found to be the best predictors. Estimating the applicant's chance of passing the GED from the ‘G’ and ‘V’ scores was discussed.