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301.
Carroll and Chang have claimed that CANDECOMP applied to symmetric matrices yields equivalent coordinate matrices, as needed for INDSCAL. Although this claim has appeared to be valid for all practical purposes, it has gone without a rigorous mathematical footing. The purpose of the present paper is to clarify CANDECOMP in this respect. It is shown that equivalent coordinate matrices are not granted at global minima when the symmetric matrices are not Gramian, or when these matrices are Gramian but the solution not globally optimal.Part of this research has been supported by The Netherlands Organization for Scientific Research (NWO), PSYCHON-grant (560-267-011). 相似文献
302.
William E. MacLean Jr. David N. Ellis Holly N. Galbreath Leslie F. Halpern Alfred A. Baumeister 《Journal of abnormal child psychology》1991,19(3):319-330
The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children — normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.This research was supported by grants from the National Institute of Child Health and Human Development (HD 17650 and HD 07226).The authors acknowledge the assistance of Robert E. Arendt, Grant Youngquist, Michael Hohn, and Charles Lowitzer in obtaining the observational data and thank the families of the subjects for their enthusiasm and dedication to the project.This study was presented at the 23rd Annual Gatlinburg Conference on Research and Theory in Mental Retardation and Developmental Disabilities, April 21, 1990. 相似文献
303.
A Troisi G Schino M D'Antoni N Pandolfi F Aureli F R D'Amato 《Behavioral and neural biology》1991,56(3):307-313
The aim of this study was to assess the validity of the notion that anxiety influences maternal style in monkeys. To this end, we investigated the correlations between measures of the quality of mother-infant relationship and scratching, a behavior pattern that reflects a state of anxiety. The subjects were seven group-living macaque mothers and their infants observed during the first 12 weeks postpartum. Postpartum scratching by the mothers was positively correlated with both maternal possessiveness and maternal warmth, two composite measures of the quality of mother-infant relationship that reflect a possessive and attentive maternal style. Evaluation of the correlations between maternal rank and scratching before and after parturition indicated that interactions with their infants, not those with other group companions, were the main source of anxiety for the mothers. These results support the notion that anxiety influences maternal style in monkeys and suggest that studies aimed at investigating physiological and social correlates of maternal emotionality in nonhuman primates could use scratching as a useful and simple behavioral measure. 相似文献
304.
Suicidal behavior in Italy: data, trends and guidelines for a suicide intervention/prevention policy. 总被引:1,自引:0,他引:1
P Crepet S Caracciolo R Casoli D Fabbri F Florenzano G M Grassi A Jonus A Tomelli 《Suicide & life-threatening behavior》1991,21(3):263-278
Even though in Italy, as in the majority of Mediterranean countries, the increase in suicide rates is not among the highest in Europe, between 1969 and 1989 it showed a sharp upswing (+43% among males and +31% among females). In terms of geographical differences, the regions with the highest suicide rate are the northern ones (up to twice the national average). The age groups with the highest suicide risk are those over 74 years (in 1989 the rate among males over 65 was the highest of all: 31.3 per 100,000). The differences in the between-sexes distribution show that among females over 65 years old the suicide rate rose by 70% between 1974 and 1989, versus 77% for males of the same age. The preliminary epidemiological results of one of two Italian centers are presented. These centers are collaborating with the WHO/EURO Multicenter Study on Parasuicide; parasuicide rates are higher for females than for males (55.9 per 100,000, as against 38.1 for males), while the age group at highest risk is seen to be young women (15-24 years), with a specific rate of 115.6. 相似文献
305.
306.
307.
Kitchener RF 《Ethics & behavior》1991,1(4):221-238
In this article, I am concerned with the ethical foundations of behavior therapy, that is, with the normative ethics and the meta-ethics underlying behavior therapy. In particular, I am concerned with questions concerning the very possibilty of providing an ethical justification for things done in the context of therapy. Because behavior therapists must be able to provide an ethical justification for various actions (if the need arises), certain meta-ethical views widely accepted by behavior therapists must be abandoned; in particular, one must give up ethical subjectivism, ethical skepticism, and ethical relativism. An additional task is to show how it is possible to provide a nonsubjective, nonskeptical, and nonrelativistic moral justification for an ethical statement. Although this is a monumental task, I provide a rough sketch of such a model, one that is congenial to the value judgments underlying behavior therapy. 相似文献
308.
BOBBY J. PRIEST S. THOMAS KORDINAK TIMOTHY F. WYNKOOP 《Journal of Addictions & Offender Counseling》1991,12(1):2-11
The Defining Issues Test (DIT) was administered to three groups of adult male inmates in two categories to compare their levels of moral development. The distribution of DIT scores was found to be similar to those of nonfelonious samples. Implications for the treatment of offender populations are discussed. 相似文献
309.
We present the steps that the Psychology Department, the Academic Computing Center (ACC), and the central administration at St. Olaf College have taken to integrate computing support into the operating budget of the college. In hindsight, we also propose a model of the diffusion of innovations into an organization as a theoretical guide to stabilizing support for computing in academic departments. The theoretical framework highlights the commonality between our particular adaptations and those that would most help at other institutions. 相似文献
310.
Our original goal was to explore the nature of the grouping-by-movement phenomenon reported by Driver and Baylis (1989). In their studies, distractors that moved in common with a centrally located target had a larger influence on focused-attention performance than did more proximate but stationary distractors. These results seemed particularly important since they suggested, contrary to the predictions of space-based models of attention, that attention could be allocated to noncontiguous regions of the visual field. Their results also suggested mandatory processing of stimuli with common motion. Unfortunately, we were unable to replicate this grouping-by-movement effect. In the conditions of Experiment 1 in which we replicated Driver and Baylis’s methodology, stationary distractors produced a larger response-compatibility effect than did the more distant distractors that moved in common with the target. In Experiment 2, we redundantly coded the centrally located target and the far distractors with common movement and color. However, the results were identical to those obtained in Experiment J. The stationary near distractors that appeared in a different color from the target and the far distractors produced the largest response-compatibility effect. In a final experiment, we attempted to compensate for the reduced acuity of the moving distractors by adjusting their size by a cortical magnification factor. However, even with this manipulation, we found a larger response-compatibility effect for the stationary near distractors than for the moving distant distractors. Our results suggest that subjects are capable of selectively processing a target item that moves in common with distractors. 相似文献