The solitaire illusion: An illusion of numerosity

A new illusion in which the apparent number of elements of two kinds is determined by their spatial arrangement is described. The illusion is such that one large cluster appears to contain more elements than several small clusters, clustering being determined by Gestalt principles. The illusion was found both in adults and in children of 8 years.     

Direction constancy

A series of experiments investigating the constancy of perceived direction was conducted. Experiments 1, 2, and 3 indicated that the perception of direction, while close to constancy, exhibited a consistent departure from constancy of approximately 2.5 deg. Experiments 4 and 5 investigated the departure from constancy in terms of the information of the position of the eyes within the head and the information of the retinal area (local sign) being stimulated. The results of these experiments indicated that the departure from constancy was a function of the underestimation of the position of the eyes within the head.     

Some properties of two measures of multivariate association

Two kinds of measures of multivariate association, based on Wilks' and the Bartlett-Nanda-Pillai trace criterionV, respectively, are compared in terms of properties of the univariateR ² which they generalize. A unified set of derivations of the properties is provided which are self-contained and not restricted to decompositions in canonical variates. One conclusion is that asymmetric index based on allows generalization of the multiplicative decomposition ofR ² in terms of squared partial correlations, but not the additive decomposition in terms of squared semipartial correlations, while the reverse is true for anasymmetric index based onV.We are indebted to Jos M. F. ten Berge for some fruitful discussions.     

Occupational Change and Career Development amongst Graduate Engineers and Scientists

Results are presented from a continuing study of men who graduated in 1970. Their first jobs after graduation were all typical of people with their degrees (in science, technology and engineering), but by 1977 they were in jobs which were identified as involving some degree of occupational change. These changes, and some of the beliefs the respondents held about them, are discussed. Tentative conclusions are drawn, and some possible implications for careers guidance are noted.     

Verb processing during sentence comprehension: Contextual impenetrability

This paper examines verb processing during sentence comprehension. We describe two experiments that assess the interaction between verb complexity and the structural information contained in a sentence. Verb complexity is defined in terms of a verb's possible argument structure arrangements—linguistic information arrayed against a verb's entry in the mental lexicon. Normal subjects had to perform a secondary task presented in the immediate vicinity of the verb while listening to a sentence for meaning. Reaction times to this secondary task show that all of a verb's possible argument structures are momentarily and exhaustively activated in the vicinity of the verb, even in sentences that are structurally biased toward one particular argument structure. We thus argue that verb processing in sentences involves a contextually impenetrable subcomponent of the language comprehension system.Program in Linguistics and Cognitive Science, Department of Psychology, Brandeis University.     

Phoneme-monitoring reaction time and preceding prosody: Effects of stop closure duration and of fundamental frequency

In an earlier study, it was shown that listeners can use prosodic cues that predict where sentence stress will fall; phoneme-monitoring RTs are faster when the preceding prosody indicates that the word bearing the target will be stressed. Two experiments which further investigate this effect are described. In the first, it is shown that the duration of the closure preceding the release of the target stop consonant burst does not affect the RT advantage for stressed words. In the second, it is shown that fundamental frequency variation is not a necessary component of the prosodic variation that produces the predicted-stress effect. It is argued that sentence processing involves a very flexible use of prosodic information.     

Sex differences in the structure of intelligence: A confirmatory factor analysis

The LISREL model of Jöreskog and Sörbom was used to perform a comparative factor analysis on intelligence data from four sex by generation groups. The covariance matrices for 10 psychometric ability measures were used to isolate Spatial and Verbal Intelligence factors. Results from a series of factor analysis models indicated substantial invariance in the factor pattern and factor covariance matrices, although the hypothesis of complete invariance in factor pattern was rejected. The groups did differ in observed and unique variances. The results were basically consistent with the hypothesis that males and females have similar intellectual structure, which would have been obscured had standardized factor analysis been employed. There were also sex and generation differences in the Spatial and Verbal factor means.     

Evaluation of self-contained training procedures for the Time-Sample Behavioral Checklist

The comparative effectiveness of two time-limited modes of training observers to code the behavior of clients in residential treatment programs on the Time-Sample Behavioral Checklist (TSBC) was evaluated. The susceptibility of training procedures to consensual observer drift and the predictability of TSBC mastery from trainee characteristics were also examined. Two equated groups of undergraduate students (N=15 each) participated in full-time training on the TSBC and another instrument for 27 days, followed by criterion testingin vivo and on videotapes. One group was trained by experienced personnel using procedures known to be effective but potentially subject to consensual observer drift. The other group was trained using a previously untested set of written and videotape procedures that do not rely on experienced personnel. Comparative effectiveness and observer drift were evaluated by multivariate and univariate ANOVAs on mastery scores reflecting both pattern agreement and level differences between each trainee and criterion codings. The new, more efficient training procedures were found to be as effective as the original training procedures in the degree of mastery achieved by trainees. Original training procedures were found to be resistant to consensual observer drift, with such a phenomenon appearing in only 1 instance of 156 opportunities. The high degree of mastery achieved by trainees during the time-limited training period was comparable to that previously achieved with the original training procedures. No meaningful predictions of coding mastery were found, with only one trainee characteristic being significantly related to one of six mastery criteria. The results document procedures that are both efficient and resistant to invalidity for training observers in the use of multidimensional observational systems, as well as providing guidelines for the development of standardized procedures.This article is based on a thesis submitted to the Graduate College of the University of Illinois at Urbana-Champaign in partial fulfillment of the requirements for the Ph.D. degree in psychology by the first author and under direction of the second author. The third and fourth authors also participated as supervisors. Appreciation is extended to other members of the thesis committee, Fred Kanfer, Ross Parke, and Julian Rappaport, and to John Gottman and W. Robert Nay for their comments and recommendations. This study was partially supported by Public Health Service Grants MH-25464 and MH-14257 from the National Institute of Mental Health and by grants from the Joyce Foundation, the MacArthur Foundation, and the Illinois Department of Mental Health and Developmental Disabilities.