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81.
82.
Transparent layer constancy   总被引:1,自引:0,他引:1  
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable.  相似文献   
83.
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   
84.
Studies in Philosophy and Education - We elaborate on Israel Scheffler's claim that principles of rationality can be rationally evaluated, focusing on foundational development, by which we mean...  相似文献   
85.
In studies using Averbach and Coriell’s (1961) partial-report bar-probe paradigm with linear arrays, most errors involve the naming of an item that was in the display but in a position other than the cued one. Up to now, there is no general agreement on the origin of these location errors. Point of departure in this paper is that part of the location errors arises from inappropriate application of the cue. It is tested whether this originates from problems to perceive the position of the cue (“cue-displacement hypothesis”) or from confusion about the order of the items in the array (“item-order hypothesis”). The results of two bar-probe experiments are reported. A novel, crucial, finding in both experiments is that, among the location errors, there was a preponderance of response letters that came from the central side of the cued item. In the second experiment, this was observed not only in the usual postcue conditions but also when the cue preceded the array. These results positively corroborate the cue-displacement hypothesis and do not support the item-order hypothesis: The cue tends to be perceived more toward the center of the visual field than it actually is exposed—that is, there is a central drift of the cue.  相似文献   
86.
This study examined the processing of supportive interactions by dysphoric and nondysphoric preteens and early adolescents. Seventy-two youngsters between the ages of 10 and 13 evaluated the supportiveness and helpfulness of standardized, videotaped interactions between a distressed preadolescent and a maternal figure. The tape presentations varied in terms of the level of depicted maternal support and instructional condition (degree of self-reference). The results indicated that dysphoric youngsters evaluated both the supportiveness and helpfulness of interactions less positively than nondysphoric agemates. Group differences in support evaluations were most pronounced in the self-referenced condition. The level of depicted support did not affect processing differences. Dysphoric subjects reported lower levels of emotional support in prior relationships and a greater tendency to view supportive behavior as ingenuine than nondysphoric peers. Variation in prior support experiences accounted for group differences in the evaluation of the supportiveness of new interactions.  相似文献   
87.
Molecular sequence data, made available in the last 15 years or so, have led to the classification of living cells into three phylogenetic domains: Bacteria, Archaea, and Eucarya. All the organisms that have been tested belonging to either domain were capable of mounting a stress response with essentially the same characteristics, regardless of the stressor. The protagonists in the cell's stress response are the stress genes and their protein products. Some of the latter are molecular chaperones. Under physiological conditions, these chaperones aid other cellular proteins to fold properly and achieve a native -functional- configuration, and to translocate from the place of synthesis to the cell's locale in which they will operate. In a stressed cell, the stress proteins that are chaperones protect other molecules from denaturation and help those partially damaged to regain a functional configuration. Thus, cell death is avoided and recovery is enhanced. The study of stress genes and proteins has progressed considerably in organisms belonging to the domains Bacteria and Eucarya. Less is known about the archaeal stress genes. Here, research with an organism from the Archaea is discussed, focusing on the stress genes of the hsp70 (dnaK) locus. Future perspectives for basic and applied research within the health sciences and biotechnology industries are presented.  相似文献   
88.
Abstract— Semantically associated and unassociated word pairs were embedded in normal meaningful sentences and in sentences that were semantically anomalous throughout The influence of lexical context was isolated via comparison of responses to the second words of the associated and unassociated pairs. The influence of sentence-level context was isolated by comparing responses to the same words in the two sentence types Subjects of high, medium and low working memory capacity (as evaluated by the reading span test) showed modulations of event-related brain potentials in response so lexical context. In contrast, only the high- and medium-capacity groups were responsive to purely sentence-level semantic context. The results demonstrate that sentential context influences the processing of words in intermediate sentence positions at normal reading speeds but that the on-line utilization of this context is more demanding of working memory than single-word contexts.  相似文献   
89.
The development of attitudes and activities of newcomers in the 18 months following the first period of socialization was investigated. At two points in time, persons' preferences for seven work climates were compared with perceived climate. Changes in person-climate fit were assessed, using a squared difference index, after alternative fit-indices were tested with hierarchical regression analysis. Person-climate fit and work attitudes at T1 (eight to ten months after entry) were examined by comparing three groups of respondents who did not change jobs, changed jobs within the organization or changed organizations. Results showed no alpha, beta or gamma changes for the total group of 108 respondents. Alpha changes were only found for respondents who changed jobs. They showed higher ratings for job satisfaction at T2. Finally, work attitudes at T1 were related to turnover. Organizational changers showed higher turnover intentions and higher discrepancies between preferred and perceived risk orientation and work pressure at T1.  相似文献   
90.
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