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981.
982.
Liss MB 《Ethics & behavior》1994,4(2):133-146
During the past 20 years, states have increasingly expanded the lists of individuals who are obligated to report their suspicions of child abuse and neglect. These legal requirements are juxtaposed with ethical considerations in research and professional practice. The ethical issues include the obligation to maintain both confidentiality of information provided by human participants and the safety and protection of these participants. This article reviews the types of state child abuse reporting statutes and outlines the categories of mandated reporters. I develop a model of how individual researchers should approach deciding whether they are mandated reporters of child abuse and neglect. 相似文献
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984.
A Pascal program that provides an analysis of the sequential dependencies between conversational events (e.g., speech acts) generated by two sources is described It produces z scores, chirsquare values, and confidence limits for the difference between estimated unconditional probabilities of the occurrence of selected events (valid events) and estimated conditional probabilities of these events following specified target events immediately (at Lag 1) and, if required, more distantly (at Lags 2, 3, etc.). Valid events and target events may be independently selected from the set of events generated by the first source, the second source, or both. Events not selected are ignored. The user may also elect to exclude the target event from the set of valid events (an adjustment for autocorrelation). The program is especially appropriate for conversational events because it does not assume that two events from the same category can never follow one another. 相似文献
985.
Cognitive function after open-heart surgery: Are postoperative neuropsychological deficits caused by cardiopulmonary bypass? 总被引:3,自引:0,他引:3
Ralph H. B. Benedict 《Neuropsychology review》1994,4(3):223-255
Despite the many technological developments in arterial perfusion and cardiac surgical procedures, open-heart surgery is still believed to pose a significant risk for cerebral injury. There are several potential causes of brain damage during open-heart surgery, including prolonged or severe arterial hypotension, as well as emboli emanating from the cardiopulmonary bypass circuit or the operative field. This article reviews the available neuropsychological studies of outcome following cardiac valve replacement and coronary artery bypass grafting. Because both procedures are life-saving operations, the research in this area has been quasi-experimental and fraught with methodological problems. Nonetheless, the findings converge to suggest that cognitive dysfunction occurs after open-heart surgery, and that the deficits are attributable, at least in part, to factors specific to the operation or to the patient being maintained on cardiopulmonary bypass. Preliminary findings suggest that embolization is the primary cause of perioperative deficits in uncomplicated operations. Studies have also consistently found preoperative deficits in this population, suggesting that neuropsychological dysfunction is caused by severe chronic cardiac disease as well as open-heart surgery. 相似文献
986.
Pizlo and Salack-Golyska (1994) have raised an important question about the validity of the interpretation of experiments reported by Lappin and Love (1992)—based on the fact that alternative cues in the image plane might have supported the shape discriminations in those experiments. The meaning of the hypothesis that visual space may be scaled by congruence under motion is clarified, pertinent evidence is reviewed, and new experimental evidence is reported We conclude that visual space can be metrically scaled by congruence of moving shapes. 相似文献
987.
Frank B. Baker 《Psychometrika》1965,30(2):165-178
The sampling properties of four item discrimination indices (biserialr, Cook's indexB, theU–L 27 per cent index, and DeltaP) were investigated in order to ascertain their sampling properties when small samples drawn from actual test data rather than constructed data were employed. The empirical results indicated that the mean index values approximated the population values and that values of the standard deviations computed from large sample formulas were good approximations to the standard deviations of the observed distributions based on samples of size 120 or less. Goodness of fit tests comparing the observed distributions with the corresponding distribution of the product-moment correlation coefficient based upon a bivariate normal population indicated that this correlational model was inappropriate for the data. The lack of adequate mathematical models for the sampling distributions of item discrimination indices suggests that one should avoid indices whose only real reason for existence was the simplification of computational procedures.This research reported herein was performed pursuant to a contract (OE-2-10-071) with the United States Office of Education, Department of Health, Education and Welfare. 相似文献
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