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91.
分时距认知特点的研究   总被引:6,自引:1,他引:5  
黄希庭  顾铸 《心理科学》1997,20(3):193-196
本研究探讨了分时距估计的认知特点,检验了SS模型、PT模型和CS模型的预测效度,结果表明:分时距估计主要是在信息提取阶段采用分段推算策略对时间信息进行重建的过程,变化/分割和注意分配对分时距估计有显著影响;SS模型的预测效度最低,PT、CS模型的预测效度较高。  相似文献   
92.
小学儿童对习俗时间的周期性特点的认知   总被引:2,自引:0,他引:2  
姜涛  方格 《心理科学》1997,20(5):431-435
本研究探讨了小学儿童对习俗时间周期性特点的认知发展.实验任务是让被试判断两个给定日期之间的时间距离是正向接近还是反向接近。结果表明:儿童对习俗时间的周期性特点的认知成绩随年龄增长而不断提高;随着两个日期之间距离的增大,反应时不断增加,正确率不断降低,在两个日期相互接近的方向发生改变的边界处,反应时最长,正确率最低,表现出显著的“距离效应”和“边界效应”;儿童可以利用数字系统进行判断,他们的认知加工策略包括计数、数字运算和凭借习俗时间的空间表象进行模拟加工等等。  相似文献   
93.
This paper discusses two forms of separability of item and person parameters in the context of response time (RT) models. The first is separate sufficiency: the existence of sufficient statistics for the item (person) parameters that do not depend on the person (item) parameters. The second is ranking independence: the likelihood of the item (person) ranking with respect to RTs does not depend on the person (item) parameters. For each form a theorem stating sufficient conditions, is proved. The two forms of separability are shown to include several (special cases of) models from psychometric and biometric literature. Ranking independence imposes no restrictions on the general distribution form, but on its parametrization. An estimation procedure based upon ranks and pseudolikelihood theory is discussed, as well as the relation of ranking independence to the concept of double monotonicity.I am indebted to Wim van der Linden for bringing Thissen's (1983) paper to my notice, and to Martijn Berger, Frans Tan, and the anonymous reviewers for their constructive comments on earlier drafts of this paper.  相似文献   
94.
Arrangements of feature sets that have been proposed to represent qualitative and quantitative variation among objects are shown to generate identical sets of set-symmetric distances. The set-symmetric distances for these feature arrangements can be represented by path lengths in an additive linear tree. Imperfect versions of these feature arrangements are proposed, which also are indistinguishable by the set-symmetric distance model. The distances for the imperfect versions can be represented by path lengths in an additive imperfectly linear tree. When dissimilarities are defined by the more general contrast model and a constant may be added to proximity data, then for both the perfect and imperfect arrangements an additive tree analysis obtains a perfect fit with an imperfectly linear tree. However, in the case of the contrast model also the distinction between the perfect and imperfect arrangements disappears in that also for the perfect arrangements the resulting tree need no longer be linear.The author is grateful to Mathieu Koppen for detailed comments on an earlier version of this article.  相似文献   
95.
The standard Pawlak approach to rough set theory, as an approximation space consisting of a universe U and an equivalence (indiscernibility) relation R U x U, can be equivalently described by the induced preclusivity ("discernibility") relation U x U \ R, which is irreflexive and symmetric.We generalize the notion of approximation space as a pair consisting of a universe U and a discernibility or preclusivity (irreflexive and symmetric) relation, not necessarily induced from an equivalence relation. In this case the "elementary" sets are not mutually disjoint, but all the theory of generalized rough sets can be developed in analogy with the standard Pawlak approach. On the power set of the universe, the algebraic structure of the quasi fuzzy-intuitionistic "classical" (BZ) lattice is introduced and the sets of all "closed" and of all "open" definable sets with the associated complete (in general nondistributive) ortholattice structures are singled out.The rough approximation of any fixed subset of the universe is the pair consisting of the best "open" approximation from the bottom and the best "closed" approximation from the top. The properties of this generalized rough approximation mapping are studied in the context of quasi-BZ lattice structures of "closed-open" ordered pairs (the "algebraic logic" of generalized rough set theory), comparing the results with the standard Pawlak approach. A particular weak form of rough representation is also studied.  相似文献   
96.
This paper describes a research program on mentally retarded parents and their children. For this nation-wide study, two structured questionnaires were sent to all municipalities in Norway. Both questionnaires were sent to public health nurses and were followed-up by a structured telephone interview based on the questionnaires. The primary aim of the study was to survey the number of children born to mentally retarded parents. In addition, the children's needs and functional abilities were to be assessed. Twenty-three mentally retarded persons had given birth in the course of the past twelve months. A total of 126 children with mentally retarded parents were identified, with an incidence of 27 children per year, and a prevalence of approximately 430 children under 16 years of age in a population of 4 mill. People with a mean of 1.05 child per family. About 43% of the children of mentally retarded parents appeared to have learning difficulties. Forty percent of the children suffered from failures of care. Between 25% and 68% of the children with learning problems had poorly developed motor or language abilities, sense modalities or psycho-social status.  相似文献   
97.
Implicit in the frame of reference hypothesis is the assumption that social comparison is one of the causal determinants of self-concept. The present study of Norwegian sixth-grade elementary school students showed that students of low-, medium-, and high-achievement classes did not differ in mathematics self-concept. Mathematics self-concept was, however, significantly influenced by the students’ within-class-room position in mathematics. The results support the frame of reference hypothesis, and the support was consistent over gender.  相似文献   
98.
Characteristics and caregiving experiences of friends and family members caring for people with AIDS (PWAs) were examined. Based on a probability sample of informal AIDS caregivers ages 18–49 living in central cities of the United States (n = 260), analyses were conducted to (a) identify the sociodemographic characteristics of young central city caregivers; and (b) examine the effects of caregiver characteristics (relationship to PWA, gender, race/ethnicity, income, sexual orientation, HIV status, perceived susceptibility), and level of objective caregiving demands, on subjective caregiver burden. Results indicate that the largest group of caregivers in this age category are male friends of the PWA—a group not typically found among caregivers to persons with other types of illnesses. In general, gay or bisexual caregivers, caregivers who have traditional family ties to the PWA, men relative to women, and lower income caregivers, report the greatest burden. While level of caregiving demands represents the most influential predictor of caregiver burden, white and male caregivers experience greater burden, independent of level of involvement and other caregiver characteristics. Receiving instrumental support with caregiving buffers the impact of high objective demands on subjective burden.  相似文献   
99.
Tested a theoretical model on the effects of social role identity, illness intrusion, and competence on psychological well-being among 109 low-income Latinas with arthritis. All six roles studied were rated as highly important identities. Sex-role nontraditionalism was associated with less importance of the homemaker, mother, and grandmother roles. Negative affect increased as a function of intrusions into valued identities. Having important role identities contributed to feelings of competence (i.e., self-esteem and self-efficacy), which in turn, contributed to psychological well-being. Competence also mediated the effects of pain, identity, and illness intrusions on psychological well-being. Results suggest competence processes play an important role in well-being.  相似文献   
100.
This paper examines internal objects in their role as theoretical constructs which analysts use to make sense of human experience. Object relations theory is based upon a vision that the personality is divided or split into parts. Clinical experience reveals that such splits are commonly expressed in the language of our analysing. However, a lexical reality is not a thing-in-itself, but a way of organizing and understanding experience. Jung's vision of the dynamics of the split self encompass a unique 'object relations theory' that is both similar and yet quite different from the object relations theories of Klein, Fairbairn, Winnicott and Thomas Ogden A clinical example is used to examine the way in which these different theoretical views explain the same clinical phenomenon. The last section of the paper is devoted to a narrational analysis of the place of internal objects in analytic theory. The split self, dynamic is seen as a narrative device - one that makes sense and provides coherence, but is neither the only view of psychic reality nor necessarily an accurate reflection of the nature of the internal world.  相似文献   
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