A Projection Caliper for Measuring at a Distance

(Frankl, Viktor E. The Doctor and the Soul. New York: Knopf, 1955. Pp. 280.) Reviewed by Robert M. Allen.     

Bias in the use of base rates: Racial prejudice in decision-making

Two studies investigated biases in the use of base rate information when assessing the probability of a witness' accurate identification of a white or West Indian as a burglar. An adapted version of the Kahneman-Tversky cab problem was used, to provide a social decision in which biases could be measured against some normative standard. Ethnicity of youth (white/West Indian) and nature of base rate (incidental/causal) were manipulated in a 2 × 2 between-subjects design. A significant interaction effect revealed that subjects took no account of the base rate for a West Indian subject, but used the base rate only when it was causal and the youth was white. This ‘prejudice effect’ against a West Indian youth and ‘exoneration effect’ for a white youth were replicated in a second study, using a microcomputer and chronometric analyses. Results are discussed in terms of heuristic decision-making, social schemata, and the cognitive versus motivational bases of bias in the use of base rates.     

Subject knowledge of the Experimenter''s interest in handedness and familial sinistrality variables and laterality test outcomes

We investigated the possible influence of common "demand characteristics" on the results on behavioral language laterality tasks. The demand characteristics were (1) whether Ss were or were not recruited for study according to their handedness, and (2) whether a detailed familial sinistrality inquiry was conducted before or after the tasks. Tasks were the Dichotic Consonant Vowel Task (DCVT) and the Bilateral Object Naming Latency Task (BONLT). Results showed no effect of demand characteristics on the BONLT. On the DCVT, however, prior inquiry regarding familial sinistrality was associated with significantly reduced right ear advantages (REAs). Interactions showed that the greatest reduction in REAs occurred in Ss with left-handedness in their families, who were asked about familial sinistrality prior to the tasks, who took the DCVT after the BONLT, and who were also recruited by handedness. Results, though generally reassuring regarding the robustness of the tasks against these sources of bias, raise some cautions for the DCVT.     

Effects of reinforcement schedules on rats' choice behavior in extinction.

The effects of reinforcement schedules on rats' choice behavior in extinction were studied. In a free-operant chamber equipped with two retractable bars, the experimental animals were trained to press the bars separately for a food reward. One bar delivered the reward on a continuous reinforcement (CRF) schedule, and the other delivered the reward on a partial reinforcement (PRF) schedule. Control animals earned the reward from both bars with the same reinforcement schedule, either a CRF or a PRF. When both bars were simultaneously available during extinction, the experimental animals responded more frequently to the CRF than to the PRF alternative, demonstrating a reversed within-subjects partial reinforcement extinction effect (PREE). A conventional between-subjects PREE was replicated in the control subjects. The results of this study were inconsistent with both Amsel's (1962, 1967) frustration hypothesis and Capaldi's (1966, 1967) sequential hypotheses.     

Computer viruses: What they are,how they work,how they might get you,and how to control them in academic institutions

A computer virus is a program that replicates itself and spreads to computers with the goal of disrupting or destroying normal computer use. In academic computing, viruses represent a serious problem that costs millions of dollars in losses annually and hinders the free exchange of information so critical to education. Viruses operate in incubation, infection, and destroy phases. The nature, mechanisms, and preventive measures for personal-computer viruses are reviewed. Different procedures are recommended to protect research laboratories, instructional laboratories, and software lending libraries. Tradeoffs between providing adequate protection and not having the security become too burdensome are considered.     

Enhancing a standard experimental delivery system (MEL) for advanced psychological experimentation

Enhancements to the Micro Experimental Laboratory (MEL) and the ways in which they facilitate development of psychological experiments are discussed in this paper. New procedures are described for (1) presenting and manipulating pictorial graphics, (2) inputting response box, voice key, joystick, digitized speech, and mouse responses, (3) outputting lights, speech, and tone stimuli, (4) editing and analyzing digitized speech, and (5) implementing multitask processing. Methods for extending the language, developing test batteries, sequencing subjects, and managing and analyzing data are described.     

Automated data collection using bar code

Using bar code technology to automate data collection provides a rapid and reliable alternative to paper-and-pencil tracking or keyboard entry into pocket or laptop computer. An array of bar code symbols is printed on a data menu, with a unique symbol corresponding to each possible observation. Bar code symbols are scanned using hand-held readers, which record the event, log the observation time, and store data for transfer to a personal computer. Advantages of the bar code monitoring system include: (1) ease of use by staff with minimal technical training, (2) reduced data entry errors and increased entry speed, (3) reliable portable operation, and (4) low-cost hardware. While the bar code system described here is used for behavioral monitoring in a residential treatment setting for the developmentally disabled, with minimal modification this system can be adapted for use in a wide variety of research and clinical applications.