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41.
42.
Jussim Lee; Nelson Thomas E.; Manis Melvin; Soffin Sonia 《Canadian Metallurgical Quarterly》1995,68(2):228
A preliminary study and 3 experiments compared predictions generated by contrasting models of how group labels bias person perception. An affective model assumed that how much perceivers like different groups mediates bias; a cognition model assumed that perceivers' beliefs regarding different groups mediates bias; and a third model assumed that both affect and cognition are necessary to mediate bias. Perceivers evaluated behavior samples provided by targets who were labeled as either rock music performers or child abusers in the preliminary study and the first 2 experiments; homosexuals or heterosexuals in the third experiment. In all studies, controlling for liking eliminated bias. The preliminary study and Study 3 also showed that controlling for beliefs about the groups eliminated bias. Structural equation modeling provided support for the affect model in Studies 1 and 2, and mixed support for the affect model and the cognition model in Study 3. These studies suggest an important role for affect in judgmental biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Age of onset reports obtained retrospectively for each symptom of DSM-III-R alcohol dependence (AD) are used to study patterns of lifetime symptom progression in a large general-population survey of people in the United States. It is shown that symptom progression among a substantial majority of respondents can be summarized as movement across three clusters. Cluster A is defined by symptoms of role impairment/hazardous use (A4), use despite social, psychological or physical problems (A6), and drinking larger amounts or over a longer period of time than intended (A1). Cluster B is defined by tolerance (A7) and impaired control (A2, A3). Cluster C is defined by withdrawal (A8, A9) and giving up activities in order to drink (A5). Clusters are shown to follow a time sequence, with at least one symptom in Cluster A usually occurring first, followed by symptoms in Clusters B and C. In all, 83.4% of the symptom cluster transitions estimated from retrospective age of onset reports are consistent with this progression. Progression to AD is differentially predicted by symptom profiles reported at the age of first symptom onset, with persons reporting Cluster C symptoms most likely to progress subsequently to AD. Furthermore, profiles of AD defined by the highest symptom cluster present at AD onset are differentially predicted by prior personal and parental histories of psychopathology and, among men, are predictive of diagnosis persistence. 相似文献
44.
45.
An optoelectronic charge coupled device (OECCD) which is directly compatible with an incident optical signal is proposed. The nonlinear partial differential equation consisting of optical generation and recombination is solved in one dimension using the Crank-Nicolson finite-difference scheme. The charge transfer inefficiency is the main parameter considered for the calculation 相似文献
46.
Qiwen Wang Xiaoyun Sun Bruce L. Golden Lenore Desilets Edward A. wasil Scott Luco Adam Peck 《Computers & Operations Research》1993,20(8)
A crucial step in manufacturing microcircuits is the wire bonding process in which a very thin gold wire must be formed to connect two surfaces in the microcircuit. The quality of the wire bond can be measured by visual inspection and a pull test—both of which are high-reliability, high-cost approaches to statistical process control. Westinghouse wanted to develop a high-reliability, low-cost quality assurance system. In this paper, we report on a year-long study to construct a neural network model that is capable of predicting the quality of wire bonds. The results of our modeling efforts reveal that neural networks are useful tools for statistical process control problems. 相似文献
47.
Unilateral spatial neglect declines when participants reach to grip the center of long metal rods compared with when they point to the perceived center, suggesting that visuomotor control systems are less affected by neglect than other representational systems (I. H. Robertson, D. Nico, & B. Hood, 1995). In this study, 16 participants with unilateral left neglect actually picked up rods, and we predicted short-term improvements in neglect because of induced conflict between a phenomenally symmetrical visual world on the one hand and a proprioceptively conveyed rightward-biased world on the other. With participants serving as their own controls, significant short-term improvements in neglect were found on 2 out of 4 neglect tasks after participants experienced proprioceptive feedback discrepant from the judgments they made on the basis of visual information alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Adaptive inverse filters for stereophonic sound reproduction 总被引:1,自引:0,他引:1
A general theoretical basis for the design of adaptive digital filters used for the equalization of the response of multichannel sound reproduction systems is described. The approach is applied to the two-channel case and then extended to deal with arbitrary numbers of channels. The intention is to equalize not only the response of the loudspeakers and the listening room but also the crosstalk transmission from right loudspeaker to left ear and vice versa. The formulation is a generalization of the Atal-Schroeder crosstalk canceler. However, the use of a least-squares approach to the digital filter design and of appropriate modeling delays potentially allows the effective equalization of nonminimum phase components in the transmission path. A stochastic gradient algorithm which facilitates the adaptation of the digital filters to the optimal solution, thereby providing the possibility of designing the filters in situ, is presented. Some experimental results for the two-channel case are given 相似文献
49.
Bruce C. Bunker R. James Kirkpatrick Richard K. Brow Gary L. Turner Carolyn Nelson 《Journal of the American Ceramic Society》1991,74(6):1430-1438
50.
McEvoy Cathy L.; Nelson Douglas L.; Holley Patricia E.; Stelnicki Glennda S. 《Canadian Metallurgical Quarterly》1992,7(3):401
Reports 2 cued recall experiments in which younger and older Ss studied target words varying in number of preexperimental associates. In Exp 1, targets were studied in either the absence or presence of meaning-related context cues, with recall always prompted by the cues. In the absence of context, words with smaller sets of associates were easier to recall than those with larger sets, but this effect was reduced for older Ss. The presence of a study context cue facilitated recall and eliminated the effect of associative set size for both ages. In Exp 2, targets were studied and tested in the presence of unrelated words. In this situation, words with smaller sets of associates were less likely to be recalled than words with larger sets; again the effect was reduced for older Ss. The results are interpreted as an age decrement in processing implicitly activated information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献