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31.
Seven hundred three members of the Society for Industrial and Organizational Psychology indicated agreement or disagreement with 49 propositions regarding cognitive ability tests in organizations. There was consensus that cognitive ability tests are valid and fair, that they provide good but incomplete measures, that different abilities are necessary for different jobs, and that diversity is valuable. Items dealing with the unique status of cognitive ability were most likely to generate polarized opinions. A 2-factor model, classifying items as those reflecting societal concerns over the consequences of ability testing and those reflecting an emphasis on the unique status of "g," fit the data well, and these factors proved especially important for predicting responses to the more controversial items. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Moore Kevin J.; Osgood D. Wayne; Larzelere Robert E.; Chamberlain Patricia 《Canadian Metallurgical Quarterly》1994,62(4):718
Pooled time series is an underused analytic technique with the potential to increase researchers' ability to exploit clinical data. This article demonstrates the value of pooled time series by analyzing the behavior of youths in a specialized foster care treatment setting in response to a naturally occurring clinical event: changes in the number of youths living together in a treatment foster care setting. Pooled time series moves beyond typical clinical analyses with an increased capability of controlling statistically for complex within-S effects and with a clinically useful measure of effect size. The complexity of the intra-S data made it virtually impossible to determine the relevant significance (i.e., clinical meaning) of the clinical event by the use of standard n?=?1 visual analysis procedures or standard statistical methods (e.g., chi square). After things such as autocorrelation and individual time trends were statistically controlled, each additional youth increased the number of problematic behaviors by one behavior per youth per day on the Parent Daily Report. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
34.
Blanchard Edward B.; Appelbaum Kenneth A.; Guarnieri Patricia; Neff Debra F.; Andrasik Frank; Jaccard James; Barron Kevin D. 《Canadian Metallurgical Quarterly》1988,56(3):427
Tension and vascular headache patients, initially treated with biofeedback and/or relaxation training in either a minimal therapist contact protocol (3 visits) or an intensive individual protocol (10 or 16 visits) were followed-up prospectively for 2 years. In the first study, for the first 6 months of follow-up, half of all patients continued to keep headache diaries and were seen monthly and the other half had only minimal contact. The results at 1-year follow-up, based on 4 weeks of daily headache diaries, revealed equally good maintenance from both treatment protocols and from both follow-up conditions. In Study 2, we found that patients remained improved over pretreatment baseline levels at the 2-year follow-up regardless of initial treatment intensity. Approximately three quarters of vascular patients who were initially improved at posttreatment remained improved at 2 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
The Cones synthesis system for automatic generation of VLSI implementations is discussed. Named for the cones in sequential logic, Cones takes behavioral models written in C and produces gate-level implementations in technologies such as standard cells and programmable logic arrays or programmable logic devices. The overall design is produced faster, more efficiently, and with fewer errors. Designers are free to concentrate on functions, instead of on the details of the implementation technology 相似文献
36.
Over the years the number of Web users has increased dramatically unfortunately leading to the inherent problem of congestion. This can affect each user's surfing experience. This paper investigates download times associated with a web request, identifies where delays occur, and provides guidelines which can be followed by web developers to enable a faster and more efficient download and service for their users. We conclude that delays in Internet traffic and congestion can often be attributed to poorly developed sites (e.g. excessive image size). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
37.
The relationship between facial expression and gaze processing was investigated with the Garner selective attention paradigm. In Experiment 1, participants performed expression judgments without interference from gaze, but expression interfered with gaze judgments. Experiment 2 replicated these results across different emotions. In both experiments, expression judgments occurred faster than gaze judgments, suggesting that expression was processed before gaze could interfere. In Experiments 3 and 4, the difficulty of the emotion discrimination was increased in two different ways. In both cases, gaze interfered with emotion judgments and vice versa. Furthermore, increasing the difficulty of the emotion discrimination resulted in gaze and expression interactions. Results indicate that expression and gaze interactions are modulated by discriminability. Whereas expression generally interferes with gaze judgments, gaze direction modulates expression processing only when facial emotion is difficult to discriminate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Kevin Parmenter 《电子与电脑》2007,(8):26-27
近来,立法工作和广告活动都把焦点集中在能源使用的一个重要方面,也是功率电子产品能够产生积极作用的地方-即待机功耗.许多法规,比如 Blue Angel(蓝天使)和Top Runner(领跑者),都要求许多电子产品的待机功耗必须小于1w. 相似文献
39.
van Wesenbeeck M.P.N. Klaasens J.B. von Stockhausen U. Munoz de Morales Anciola A. Valtchev S.S. 《Industrial Electronics, IEEE Transactions on》1997,44(6):780-787
Series connection of power devices has evolved into a mature technique and is widely applied in HV DC power systems. Static and dynamic voltage balance is ensured by shunting individual devices with dissipative snubbers. The snubber losses become pronounced for increased operating frequencies and adversely affect power density. Capacitive snubbers do not exhibit these disadvantages, but they require a zero-voltage switching mode. Super-resonant power converters facilitate the principle of zero-voltage switching. A high-voltage DC-DC power converter with multiple series-connected devices is proposed. It allows the application of nondissipating snubbers to assist the voltage sharing between the multiple series-connected devices and lowers turnoff losses. Simulation results obtained with a circuit simulator are validated in an experimental power converter operating with two series-connected devices. The behavior of the series connection is examined for MOSFETs and IGBTs by both experimental work with a 2 kW prototype and computer simulation. Applications can be found in traction and heavy industry, where the soft-switching power converter is directly powered from a high-voltage source 相似文献
40.
Kevin Burns 《Information Sciences》2006,176(11):1570-1589
Bayesian inference provides a formal framework for assessing the odds of hypotheses in light of evidence. This makes Bayesian inference applicable to a wide range of diagnostic challenges in the field of chance discovery, including the problem of disputed authorship that arises in electronic commerce, counter-terrorism and other forensic applications. For example, when two documents are so similar that one is likely to be a hoax written from the other, the question is: Which document is most likely the source and which document is most likely the hoax? Here I review a Bayesian study of disputed authorship performed by a biblical scholar, and I show that the scholar makes critical errors with respect to several issues, namely: Causal Basis, Likelihood Judgment and Conditional Dependency. The scholar’s errors are important because they have a large effect on his conclusions and because similar errors often occur when people, both experts and novices, are faced with the challenges of Bayesian inference. As a practical solution, I introduce a graphical system designed to help prevent the observed errors. I discuss how this decision support system applies more generally to any problem of Bayesian inference, and how it differs from the graphical models of Bayesian Networks. 相似文献