Relational perception and modes of perceiver operation

Judgments were made of the size of a small, luminous (inner) square appearing in the center of a somewhat larger, variable (outer) square, the whole pattern appearing in the dark. Accuracy of judgment was greatest when the outer square was constant from trial to trial but deteriorated when the outer square also varied in size, reaching a lower limit less than the accuracy produced under the absolute judgment condition (no outer square presented). An application of multiple discriminant analysis and the use of a maximum likelihood observer model provided estimates of the extent to which Os responded to inner and outer size variation as separate aspects of stimulation. Although Os differed markedly in this respect, their ability to identify inner square size under the various conditions did not reflect this difference.     

A cognitive probability model for learning

A quantitative model for the behavior of albino rats in choice-making situations is presented. The model, which is based upon a cognitive conceptualization of the learning process, is shown to yield predictions which are equivalent to those produced by the linear operator stochastic models at the asymptotic limit but which differ from these during early trials in the learning situation.     

Varying temporal placement of an added stimulus in a fixed-interval schedule

One paradigm for exploring stimulus effects on behavior is defined for steady state experiments. The paradigm is illustrated by a 60-sec fixed-interval reinforcement schedule wherein a 6-sec light is introduced into each interval. The temporal relation of this stimulus to the reinforcer is the independent variable that is systematically explored. Two experiments studied this temporal relation under two parametric conditions: (a) when the 6-sec light occurs once in each 60-sec interval, (b) when the 6-sec light occurs twice in each interval, the second time always during the 6 sec immediately preceding the reinforcer. Functions are presented showing the effect of the 6-sec light on responding at all points in the fixed-interval.     

The use of rats as discriminative stimuli

A FREE OPERANT PROCEDURE WAS USED TO DETERMINE WHETHER OR NOT ONE RAT COULD DISCRIMINATE: (1) between the presence and absence of a second rat, and (2) between two other rats of the same species and sex. The subjects were four male Wistar rats. The discriminatory response was a bar press and food was used as reinforcement during training. Although there were wide individual differences in rate of learning, all subjects learned to make both discriminations.     

Changes in Academic Performance in the Junior High School

This study was designed to determine the relationships between changes in academic performance and intellective and non-intellective factors. Seventh grade students attending five junior high schools, who had attended selected elementary schools, were tested with the Personal Values Inventory (PVI), a test of academic motivation, shortly after the first seventh-grade marking period. School marks at that marking period and those received the previous year were procured from a self-report included in the PVI. All students had taken the California Achievement Test Battery and Mental Maturity Test as well as the Scholastic Testing Service Work-Study Skills Test in the sixth grade. Factor analysis identified four factors in both boys and girls: intelligence-achievement, academic motivation, academic plans, and youth-culture involvement. While intelligence was found to be mainly unrelated to the criterion, the non-intellective factors, especially academic motivation, bore significant relationships to the changed performance.     

Attitudes of American Secondary School Students Toward the Use of Intelligence Tests

A national sample of about 5,000 public, 2,600 parochial, and 1,200 private secondary school students were asked whether they thought it fair to use intelligence tests to help make decisions in educational, occupational, and other areas. Results indicated that: (1) anti-test sentiment is neither ubiquitous nor consistent. A considerable number of respondents were in favor of testing, the proportion of respondents favoring tests varied greatly as a function of test context, and some favored tests in one context but disapproved of them in another. (2) Social background and individual difference variables interacted with test contexts. Given two test contexts, these variables may have different effects for each in determining the respondent's approval or disapproval of test usage.