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181.
Reversal and nonreversal shifts by cats and rhesus monkeys 总被引:1,自引:0,他引:1
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The influence of background reflectance was determined for lightness judgments relative to white of small gray patches. The effect of prior stimulus-context was avoided by considering only first judgments. It was found that lightness was proportional to the square root of reflectance when the background was a gray darker than the stimulus, but not when the background was lighter gray or white. In general, a small difference in reflectance between the stimulus and and background produced the same effect as a larger difference. 相似文献
183.
In this article the authors examine the effect of including alternate test forms in a factor matrix upon the validity of the resultant factor loadings, finding that in this particular instance the effect is negligible. Comparisons of the factor loadings derived from matrices in which only one of the alternate test forms is included with those in which both forms are included reveal practically no difference in the magnitude of either the original or rotated factor loadings, or in that of the computed communalities. 相似文献
184.
The corporatization of U.S. health care has directed cost containment efforts toward scrutinizing the clinical decisions of physicians. This stimulated a variety of new utilization management interventions, particularly in hospital and managed care settings. Recent changes in fee-for-service medicine and physicians' traditional agency relationships with patients, purchasers, and insurers are examined here. New information systems monitoring of physician ordering behavior has already begun to impact on physician autonomy and the relationship of physicians to provider organizations in both for-profit and ‘not-for-profit’ sectors. As managed care practice settings proliferate, serious ethical questions will be raised about agency relationships with patients. This article examines health system dynamics altering the historical agency relationship between the physician and patient and eroding the traditional autonomy of the medical profession in the United States. The corporatization of medicine and the accompanying information systems monitoring of physician productivity is seen to account of such change, now posing serious ethical dilemmas. 相似文献
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Warren Spielberg 《Psychoanalytic Dialogues》2017,27(3):366-368
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Foo P Warren WH Duchon A Tarr MJ 《Journal of experimental psychology. Learning, memory, and cognition》2005,31(2):195-215
Do humans integrate experience on specific routes into metric survey knowledge of the environment, or do they depend on a simpler strategy of landmark navigation? The authors tested this question using a novel shortcut paradigm during walking in a virtual environment. The authors find that participants could not take successful shortcuts in a desert world but could do so with dispersed landmarks in a forest. On catch trials, participants were drawn toward the displaced landmarks whether the landmarks were clustered near the target location or along the shortcut route. However, when landmarks appeared unreliable, participants fell back on coarse survey knowledge. Like honeybees (F. C. Dyer, 1991), humans do not appear to derive accurate cognitive maps from path integration to guide navigation but, instead, depend on landmarks when they are available. 相似文献
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