Forms can be recognized from dynamic occlusion alone

Direct and indirect theories of perception differ on whether form perception depends on higher order invariants or on features in the retinal image. The present paper describes a demonstration that an object can be recognized through a higher order pattern (dynamic occlusion) without any of the object's features being displayed. Stimuli consist of computer stimulations of black wireframe objects moving in front of, and occluding, a random layout of point lights on a black background. In this way, no single videoframe of the stimuli displays any of the object's features, and motion of the amodal object in front of the light points is necessary for the form to become visible. The forms can also be recognized when isoluminous colours are used for background and point lights. Finally, it is noted that, if the observer can actively control the motion of the object, e.g., by moving a computer mouse, recognition is enhanced as in Gibson's (1962) experiment on active touch.     

APPLICANT AGE AND SELECTION INTERVIEW DECISIONS: EFFECT OF INFORMATION EXPOSURE ON AGE DISCRIMINATION IN PERSONNEL SELECTION

Two research questions pertaining to the applicant age bias effect were addressed in this study: the effect of age-related information exposure on selection decisions and the issue of between-sample generalizability with reference to the age bias effect. Manager and student selectors made selection decisions after viewing one videotape of a simulated selection interview of either an old or a young job applicant. Before viewing the interview tape, half of each subject group was given an item of age-related information and the other half was given neutral information. The results showed that, under the neutral information condition, managers preferred hiring the young applicant for the low-status job, and students favored the old candidate for the high-status position. Under the age-related information condition, managers shifted to favoring the old candidate for the low-status job, and students preferred the young applicant for both the low- and high-status positions. Age discrimination in selection decisions and the lack of external validity of student results in selection research are then discussed.     

Comparability of WAIS and WAIS--R scores among mentally retarded adults

This study compared the performance on the WAIS and WAIS--R of 21 mentally retarded adults residing in an Intermediate Care Facility. Tests were administered in one order, the WAIS initially and the WAIS--R second, with approximately two years between testings. Significant differences were found on the WAIS and WAIS--R for Verbal, Performance and Full Scale IQs. This finding contrasts with the differences between the measures as reported in the WAIS--R manual.     

Helping the child with cancer: what school personnel want to know

As more children with cancer survive, the importance of facilitating school reintegration as a part of maximizing the quality of life has become evident. Workshops have been presented to school personnel to acquaint them with the issues facing cancer patients and their families, but there are gaps in our knowledge of what school personnel really need or want to know. In this study, 18 teachers of children with cancer and 15 teachers with no prior contact with students with cancer completed a questionnaire designed to assess needs, beliefs, and priorities with regard to working with cancer patients in the classroom. Significant findings included: (a) a consensus that a certain core of information about medical/psychological issues would be useful, and presentation of such information by psychologists and medical personnel working with such families would be optimal; (b) teachers having cancer patients as students were less likely to see the adaptation of siblings as an important issue; (c) teachers associated working with a student with cancer with less stress and demands on their time than predictable from previous studies; and (d) cancer patients as a whole were rated as having fewer behavioral, emotional, and learning problems than randomly selected students without a major illness, suggesting a "halo effect" or contradiction of some literature. Preliminary findings are detailed and implications are discussed for those attempting to help teachers facilitate students' adjustment to school following diagnosis and treatment of cancer.     

Comparisons of parents', teachers', and students' perceptions of self-concept in children from one- and two-parent families

19 pairs of third grade children from intact and single-parent families matched for sex, intellectual ability, and academic achievement were administered a brief self-concept measure. Teachers and parents rated the students' self-concept on similar measures. There were no significant differences in scores between the groups; however, within each group the teachers and parents consistently overestimated students' self-esteem.     

A quasi-nonmetric method for multidimensional scaling VIA an extended euclidean model

An Extended Two-Way Euclidean Multidimensional Scaling (MDS) model which assumes both common and specific dimensions is described and contrasted with the standard (Two-Way) MDS model. In this Extended Two-Way Euclidean model then stimuli (or other objects) are assumed to be characterized by coordinates onR common dimensions. In addition each stimulus is assumed to have a dimension (or dimensions) specific to it alone. The overall distance between objecti and objectj then is defined as the square root of the ordinary squared Euclidean distance plus terms denoting the specificity of each object. The specificity,s _j , can be thought of as the sum of squares of coordinates on those dimensions specific to objecti, all of which have nonzero coordinatesonly for objecti. (In practice, we may think of there being just one such specific dimension for each object, as this situation is mathematically indistinguishable from the case in which there are more than one.)We further assume that _ij =F(d _ij ) +e _ij where _ij is the proximity value (e.g., similarity or dissimilarity) of objectsi andj,d _ij is the extended Euclidean distance defined above, whilee _ij is an error term assumed i.i.d.N(0, ²).F is assumed either a linear function (in the metric case) or a monotone spline of specified form (in the quasi-nonmetric case). A numerical procedure alternating a modified Newton-Raphson algorithm with an algorithm for fitting an optimal monotone spline (or linear function) is used to secure maximum likelihood estimates of the paramstatistics) can be used to test hypotheses about the number of common dimensions, and/or the existence of specific (in addition toR common) dimensions.This approach is illustrated with applications to both artificial data and real data on judged similarity of nations.     

Performance of the vertical position in synchronized swimming as a function of skill, proprioceptive and visual feedback

This experiment assessed the efficacy of proprioceptive and visual information for the performance of "vertical position" by synchronized swimmers. Three skill groups of 5 senior, 5 intermediate, and 5 novice synchronized swimmers performed 40 vertical positions under four conditions. The conditions were: self-initiated with and without vision, and following experimenter perturbation, with and without vision. The dependent measure was degrees of error from true vertical. Analysis indicated that either proprioception or proprioception and vision may be used in performing vertical positions. A significant main effect was found among skill groups.     

Behavioral sequelae of long-term self-attributed success and failure: an attribution theory analysis

Starting from earlier results that self-caused long-term failure improved performance, this experiment tested the effect of "working conditions" as well as successes and failures succeeding the experience of long-term success and long-term failure. 64 subjects participated in recognition tests, composed of 9 tasks (with 42 stimuli each), to be solved within five different experimental sessions. Subjects received false feedback concerning each judgement. The feedback was designed to correspond to Kelley's informational requirements for self-attributions. Results clearly show an impairment of performances within new "working conditions" if successes succeed long-term failure or long-term success. Failure succeeding long-term failure in new "working conditions", on the other hand, improves performance. Different attribution theories' capacity to explain these results is discussed.