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.     

Effects of grammaticalness, presentation rate, and message length on auditory short-term memory

The aim of this study was to demonstrate the effect of message structure, message length, and presentation rate upon auditory short-term memory. Subjects were asked to reproduce in writing messages at different levels of “grammaticalness” (Coleman, 1965) presented through headphones at 3-4 words/sec. or 6-7 words/ sec. There was better recall of the more structured, shorter, and slower messages. The results are discussed in terms of acquisition and encoding of information.     

Prismatic displacement and the remembered location of targets

Following adaptation, only the trained limb misreaches to the remembered location of targets. This suggests a change in the feit position of the trained limb, but conflicts with recent reports, and with the hypothesis that when a limb changes, the remembered location of targets encountered only by that limb undergo some change too. It suggests that information is stored independently of the mode of acquisition.     

Similarity of schematic faces: A test of

In this study we obtained direct and comparative judgments of the dissimilarity between schematic faces varying on three binary attributes. These data were used to test the hypothesis that the overall dissimilarity between faces can be decomposed (in an ordinal sense) into three additive components, one for each attribute. The hypothesis was strongly confirmed by both the direct and the comparative judgments. The study illustrates the possible usefulness of the measurement-theoretic analysis of simple combination mies for psychological dimensions.     

Similarity judgments of line length

Nine Ss judged similarity of pairs of lines on a scale from 0 to 100, and 14 Ss made magnitude estimations of similarity of pairs of lines. The two scales of similarity were linearly related. Scale values for subjective length were obtained in one dimension using a nonmetric multidimensional analysis. Subjective length was found to be logarithmically related to objective length, and similarity was found to be an exponential     

Orientation of letters and errors in their recognition

Subjects named alphabetic characters that had been rotated, reflected, or inverted. Inversions induce more errors than mirror reflections and reflections induce more than rotations. In a significant number of mistakes a transformed character was assumed to be normally oriented, but in most a transformed character was confused with the mirror image of the original. The data suggest the existence of an “orientation set” in which the identiflcation of ambiguous characters depends largely on their anticipated orientation. The individuality of the data for the different orientations suggests that different transformations are compensated for in part by different mechanisms.