PROSS: A process control programming language

PROSS, a programming language for small- and medium-scale process control computers, is presented. The PROSS language, whose structure and syntax were expressly designed for ease of use by psychologists, is summarized and exemplified in a sample procedure. The structure of an existing PROSS compiler is briefly summarized.     

A test of the assumptions of multidimensional scaling by separating sensitivity and response bias

Summary This study investigates one of the main assumptions underlying multidimensional scaling models. It is tested whether the violation of decomposability found in previous studies can be explained by variation in sensitivity or in response bias. Rectangles of different shape served as stimuli in an experiment using a matching procedure. In addition the probability for presenting pairs of identical stimuli was varied. The data were analysed by a model separating response bias and sensitivity. Six versions of the model with different numbers of parameters were applied. The results suggest that the violation of decomposability comes from variation in sensitivity and not in response bias.This research was supported by a grant from the Deutsche Forschungsgemeinschaft to the first author. All computing was done on the Telefunken TR 440 of the Deutsches Rechenzentrum Darmstadt.     

On counteradaptation

Often adaptation to artificially altered stimulation takes place because veridical stimulation that produces the same perceptual property that is produced by the altered stimulation is also received. In these cases, an assimilation of the two perceptual processes produced by the two different stimulations (the altered and the veridical) is supposed to be responsible for the adaptation that is achieved. This hypothesis, which was formulated by Wallach and Karsh (1963), would be confirmed by demonstrating a modification of the perceptual process produced by veridical stimulation rather than the one produced by the altered stimulation. We demonstrated this by having S observe in the dark for 20 min a luminous figure that objectively expanded as it moved toward S and contracted as it moved away. But instead of testing for changes in size perception as such, we tested for a change in the relation between accommodation and convergence on the one hand and registered distance on the other. In one experiment, such a change was measured by obtaining estimates of perceived size and depth before and after the adaptation period. Highly significant changes of size and significantly greater changes of stereoscopic depth were obtained. Inasmuch as stereoscopic vision was totally absent from the adaptation conditions, the change in stereoscopic depth that was larger than the size change can only be ascribed to a change in registered distance. In another experiment, we tested for a change in distance by having S point from the side to a vertical line, before and again after the adaptation period, under conditions where only accommodation and convergence could serve as distance cues. Significant changes in the pointing distance were measured, indicating more directly a change in the relation between these oculomotor adjustments and perceived distance. We propose the term counteradaptation for such modification of a perceptual process away from veridicality.     

The disputation — a special type of cooperative argumentative dialogue

This article consists of three parts, two introductory, in which the limits and the methods of analysis of dialogues are expounded, and the major part, in which the main features of a philosophical theory of disputation are outlined.

Societal risks as seen by a Norwegian public

In two studies, questionnaires originally developed to study risk perception in the United States were administered to Norwegian students. Level of perceived risk in Norway was clearly below American scores for most hazards, but slightly above what has been found in a parallel Hungarian study. Norwegians were more concerned than both Hungarians and Americans about narcotics, but less than Americans about chemicals used in food and agriculture, and less than Hungarians about a number of common, everyday hazards. When ratings on nine risk characteristics were factor analyzed, a two dimensional solution was found with Fatal risk and Involuntary risk as the two most important dimensions. Ratings of general death risk, harm risk, and death risk for those exposed were highly correlated, but appeared to be unrelated to the number of people believed to be exposed to the hazard.     

Influence and Selection In the Friend-adolescent Relationship: Findings from Studies of Adolescent Smoking and Drinking1

The importance of friend influence as a determinant of adolescent behavior has primarily been inferred from research that has repeatedly demonstrated the behavior of friends to be similar. Homogeneity among peers, however, could also be due to a selection process whereby adolescents choose and keep friends whose behavior is similar to their own. Most previous studies have used cross-sectional designs that cannot delineate the source of peer homogeneity; this study employed sociometric data from longitudinal research on adolescent smoking and drinking to separate and examine the selection and influence processes. Although the findings indicate some support for the friend influence model, the acquisition hypothesis from the selection model accounts for substantially more of the adolescent-friend relationship. The implications of these results for past and future research concerning the role of peers in adolescence are discussed.     

DADTA VI: A minicomputer-based video control system for the analysis of behavioral and electrophysiological data

A computer-automated testing apparatus for monkey and human subjects is described. This dual-computer system generates programmable color video displays and permits on-line collection of behavioral and electrophysiological data. Video displays are generated by an Apple II minicomputer linked via a serial transmission port to a general-purpose laboratory computer (DEC PDP-11/34). Control of event sequences is determined by serial interaction between the two computers. Software (programs) for the collection and analysis of event-related brain potentials data is described, and the experimental and clinical applications of this DADTA VI (Discrimination apparatus for discrete-trial analysis, Version 6) for neuropsychology are discussed.     

The effects of dynamic assessment procedures on Raven Matrices performance,visual search behavior,test anxiety and test orientation

The effects of dynamic testing procedures on Raven Coloured Matrices performance, visual scanning procedures, test anxiety, and orientation to the test situation were assessed. The subjects were 72 third-grade children. The results supported the hypotheses of the study showing that (1) dynamic assessment procedures involving either verbalization or elaborated feedback lead to higher levels of Raven Matrices performance; that (2) dynamic assessment modifies visual search behaviors; and that (3) dynamic assessment reduces test anxiety and negative orientation to the testing situation. The results are interpreted as offering construct validation to the assessment approaches used.