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51.
The notion of unsharp orthoalgebra is introduced and it is proved that the category of unsharp orthoalgebras is isomorphic to the category of D-posets. A completeness theorem for some partial logics based on unsharp orthoalgebras, orthoalgebras and orthomodular posets is proved. 相似文献
52.
The developmental consequences of homelessness have only recently begun to be investigated. This study examined the effects of homelessness on the self-concept, behavioral symptoms, and emotional development of preschoolers. Self-concept was examined using the Pictorial Scale of Perceived Competence and Acceptance for Young Children and teachers rated behavioral symptoms using the Child Behavior Checklist. Emotional development was also examined. Results showed that homeless preschoolers have lower self-concepts and display more deviant behaviors on the Child Behavior Checklist than housed preschoolers of the same socioeconomic status. Recognition and understanding of emotion, however, were similar in both groups.Research was supported by a grant from the Department of Health and Human Services, Administration for Children and Families. The authors would like to express great appreciation to teachers Michaelene Blazak and Mary Ellen Ranta, to homeless case aide Elizabeth Davico, and to research assistant Carolyn Boumilla-Agostini for their assistance and dedication. 相似文献
53.
To further test role constraint and socialization theories of gender differences in coping, two studies were conducted to examine coping strategies in individuals occupying similar roles. The relations between coping strategy frequency and effectiveness and between coping strategy use and psychological functioning also were examined. Predominantly Caucasian female and male college students participated in the studies. Results indicated support for both socialization and role constraint theories. Effectiveness and frequency of coping strategy use were moderately correlated. Gender differences in cognitive appraisal varied with dispositional vs. situational assessment. The need for a more integrated model to explain gender differences in coping and implications for existing theories are discussed. 相似文献
54.
James Amirkhan Hector Betancourt Sandra Graham Steven Regeser Lpez Bernard Weiner 《Psychological science》1995,6(3):140-148
Four goals of affirmative action in higher education are described as they relate to psychology admissions. Broadly conceived, these goals are compensating for past injustice, correcting present inequity, promoting intellectual diversity, and enhancing the presence of role models. It is argued that the four goats differ in their underlying assumptions about the purposes of affirmative action and that these differences can result in disparate admission decisions. Data from three experiments on decision making in graduate psychology admissions are presented to illustrate the analysis. In these studies, academic psychologists rated the admissibility of hypothetical graduate student applicants who varied on a number of characteristics (e g., ethnicity, social class, interest in minority research) pertinent to affirmative action. A consistent pattern of ethnic group differences in admissibility ratings was documented, illustrating that compensation for past injustice can be interpreted as a salient affirmative action goal in graduate admissions decisions. Implications of the analysis for clarifying admissions decisions guided by affirmative action goals are discussed. 相似文献
55.
56.
Roberto Miraglia 《Axiomathes》1995,6(2):169-195
This article sets out the overall framework within which American music phenomenologists operates. A widely accepted definition of the word phenomenology, together with a basically eclectic attitude and a boundary issue between musicology and philosophy, is identified. The impetus to the article is provided by an anti-positivistic polemic and a plea in defence of the meaning and concreteness of musical experience. These aspects then combine in a critique of traditional musical analysis in its positivistic matrix. S.K. Langer's philosophy, as the inspiration of this polemic, is examined in the central part of the article. However, the author's distancing from the idealistic aspects of his esthetics is covered, in particular the downplaying of the sound-sensitive level and the condemnation of musicology in general. Sense and sensitive materials, wide philosophical options and concrete procedures of music analysis are what these authors look for in phenomenology as a means to reconcile humanistic and technical culture. Therefore, the article is not so much a condemnation as an attempt to refound musicology in its entirety, with particular reference to contemporary music. 相似文献
57.
Zellini (1979, Theorem 3.1) has shown how to decompose an arbitrary symmetric matrix of ordern ×n as a linear combination of 1/2n(n+1) fixed rank one matrices, thus constructing an explicit tensor basis for the set of symmetricn ×n matrices. Zellini's decomposition is based on properties of persymmetric matrices. In the present paper, a simplified tensor basis is given, by showing that a symmetric matrix can also be decomposed in terms of 1/2n(n+1) fixed binary matrices of rank one. The decomposition implies that ann ×n ×p array consisting ofp symmetricn ×n slabs has maximal rank 1/2n(n+1). Likewise, an unconstrained INDSCAL (symmetric CANDECOMP/PARAFAC) decomposition of such an array will yield a perfect fit in 1/2n(n+1) dimensions. When the fitting only pertains to the off-diagonal elements of the symmetric matrices, as is the case in a version of PARAFAC where communalities are involved, the maximal number of dimensions can be further reduced to 1/2n(n–1). However, when the saliences in INDSCAL are constrained to be nonnegative, the tensor basis result does not apply. In fact, it is shown that in this case the number of dimensions needed can be as large asp, the number of matrices analyzed. 相似文献
58.
GLOBAL PROCESSING-TIME COEFFICIENTS CHARACTERIZE INDIVIDUAL AND GROUP DIFFERENCES IN COGNITIVE SPEED 总被引:2,自引:0,他引:2
Abstract— Forty participants performed seven different information processing tasks (choice reaction time, letter classification, visual search, abstract matching, line-length discrimination, mental rotation, and mental paper-folding) Slow (top quartile) and fast (bottom quartile) processors were selected based on their mean z scores Response times (RTs) of the slow and fast groups in the 21 conditions of the seven tasks were linear functions of the mean RTs of the entire group (both r2 s = 99) In addition, individuals' RTs were well described by linear functions (median r2 = 93) When tasks were ranked in order of complexity, the odd-even reliability of the ratio of an individual's RT to the average RT was 80, indicating that such ratios remain relatively stable across tasks Taken together, these findings indicate that the performance of an individual on diverse tasks can be predicted on the basis of a single processing-time coefficient Such coefficients may provide useful indices of the efficiency with which different individuals process information 相似文献
59.
Scarr S 《Ethics & behavior》1994,4(2):147-155
The articles by Brooks-Gunn, Fisher, Hoagwood, Liss and Scott-Jones (all in this issue) present a panoply of real-world ethical issues in conducting scientific research on risky behaviors of children, adolescents, and their parents, particularly those from vulnerable populations. The universal, ethical principles of beneficence, justice, and respect for others are always applicable, but they do not resolve issues of child assent, parental consent, legal reporting requirements for illegal behaviors, and the special problems of studying risky behaviors in risky populations. Taken as a group, the articles raise some of the most interesting ethical problems that arise in developmental research. My discussion elaborates some issues and fails to resolve others. I hold the view that both science and ethics can be served by thoughtfully designed and implemented research on important social issues, but that the studies themselves cannot simultaneously solve the many societal problems of participants and be scientifically credible. 相似文献
60.
The effects of maternal employment and non-maternal infant care on development at two and four years
Differences in maternal employment during children's first year of life and children's entry into non-maternal care before the age of 1 year failed to predict differences in cognitive and socioemotional development at 2 and 4 years of age, after family background variables were controlled. Two samples were studied: a population sample of 1100 Bermudian children and a smaller subsample of children most of whom were determined to be at risk for developmental problems. To assess the effects of maternal employment, we compared infants with mothers who worked 20 or more hours a week to infants with mothers who worked less than 20 hours a week. To assess the effects of entry into non-maternal care before the age of one, we compared infants who were placed in regular non-maternal care before the age of one versus infants who did not experience regular non-maternal care before the age of one. The results revealed that family background variables frequently predicted many child outcome measures in both the total sample and the smaller research sample. After controlling for family characteristics, no differences were found between children whose mothers worked 20 or more hours a week when they were infants and children with mothers who worked less than 20 hours a week in either sample. In addition, age of entry into non. maternal care before the age of one did not significantly predict any child outcome measures. 相似文献