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91.
As the principle of timing or opportunity,kairos serves both as a powerful theme within technological discourse and as an analytical concept that explains some of the suasory force by which such discourse maintains itself and its position in our culture. This essay makes a case for a rhetoric of technology that is distinct from the rhetoric of science and illustrates the value of the classical vocabulary for understanding contemporary rhetoric. This case is made by examining images and models of technological change that underlie and justify the thematizations ofkairos that appear in so much technological discourse and by exploring the phenomenon of technological forecasting, in which the characterization and construction of moments in the present are crucial to the projection of the future. One example of forecasting is examined in detail: the Japanese Fifth Generation computer project, which illustrates the twin themes of opportunity and threat.  相似文献   
92.
Subjects chose between pairs of hypothetical amounts of money available after different delays. When smaller, more immediate amounts were selected over larger, more delayed amounts, the addition of a constant delay to both outcomes resulted in reversals of preference, contrary to the standard discounted utility model of economics. The delays at which preference reversed were determined for three pairs of amounts ($20 vs. $50, $100 vs. $250, and $500 vs. $1,250). The relation between the delay to the larger amount and the delay to the smaller amount at preference reversal was well fit by both linear and quadratic functions. Intercepts increased with amount, strongly suggesting that rate of discounting decreases with amount. The presence of significant negative curvature in the data from the majority of individual subjects poses problems for exponential and hyperbolic models of temporal discounting in self-control, both of which predict a linear relation between the delays to the larger and smaller amounts.  相似文献   
93.
In two experiments, a concurrent discrimination paradigm was used to study the effects of visual attention on psychophysical judgments and the consistency of these effects with a sample-size model in which attention influences the variance of the internal representation used to make psychophysical judgments. Two pairs of lines were presented simultaneously—one on each side of fixation—and subjects had to indicate for each pair separately whether or not the lines had the same length. Attention was manipulated by instructing subjects to pay 100%, 75%, 50%, 25%, or 0% of their attention to the discrimination on one side, with the complementary amount of attention to the other side. In the first experiment, the relationship between attention and discrimination accuracy was consistent with the sample-size model both when attentional allocation varied from trial to trial and when it varied between blocks, and the relationship held over more widely varying attentional allocations than had previously been studied. In addition, discriminations were more accurate overall with varied than with blocked attentional allocation, suggesting that the two types of allocation do not merely differ in the degree to which attention is focused. The second experiment examined the effects of attentional allocation and stimulus variance, the latter being manipulated by randomly incrementing or decrementing line lengths. These manipulations had additive effects on total Thurstonian variance, and a version of the samplesize model gave an excellent quantitative fit to the obtained results. Besides supporting the samplesize model, the results of Experiment 2 suggest that criterion variance is at least as large as sensory variance and that criterion but not sensory variance increases with stimulus variance.  相似文献   
94.
Four experiments were performed in order to examine the effect of gap depth on human observers’ perception of whether or not a gap is crossable. Experiments 1 and 2 showed that as the gap’s depth increased, observers tended to increasingly underestimate the maximum width of a gap they could step across. Experiments 3 and 4 clarified this finding: The observed covariation of perceived gap crossability and gap depth depended on the observer’s direction of gaze, rather than on the physical depth of the gap. The optical relations to which observers might be attending are discussed, as well as the possibility that cognitive-affective processes might have contributed to observers’ underestimation of their actual capabilities.  相似文献   
95.
Co-morbidity of alcohol and substance with the spectrum of other psychiatric diagnoses is examined with specific emphasis on diagnostic indicators for anxiety and mood disorders. Diagnostic issues for the chemically dependent person are examined with the context of borderline personality disorder, schizophrenia and other psychiatric disorders. Clinical research related to the dually-diagnosed patient is explored  相似文献   
96.
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training.  相似文献   
97.
The available literature indicates that: (a) experiences of childhood violence are associated with mediator variables, including antisocial behaviors and depressive symptomatology, that are themselves associated with development of alcohol problems and perpetration of partner violence for men in adulthood; (b) experiences of childhood violence and, more strongly, observation of interparental violence during childhood predict perpetration of partner violence in adulthood for males; (c) presence of partner violence is associated with certain types of alcohol problems for men; and (d) both partner violence and alcohol problems are associated with marital conflict. However, available research has often excluded important moderator variables, such as history of familial and parental alcohol problems and history of parental psychiatric disorders. Based on the available research, two indirect pathways between childhood violence and adulthood problems (i.e., alcohol problems and partner violence) are proposed as guides for future research in the areas of family violence and alcohol problems for men. Further, bidirectional associations between alcohol problems and partner violence are proposed. Finally, inclusion of important moderator and mediator variables in multivariate research designs is suggested.  相似文献   
98.
The distribution of sample $\hat d's$ , although mathematically intractable, can be tabulated readily by computer. Such tabulations reveal a number of interesting properties of this distribution, including: (1) sample $\hat d's$ are biased, with an expected value that can be higher or lower than the true value, depending on the sample size, the true value itself, and the convention adopted for handling cases in which the sample $\hat d'$ is undefined; (2) the variance of $\hat d'$ also depends on the convention adopted for handling cases in which the sample $\hat d'$ is undefined and is in some cases poorly approximated by the standard approximation formula, (3) the standard formula for a confidence interval for $\hat d'$ is quite accurate with at least 50–100 trials per condition, but more accurate intervals can be obtained by direct computation with smaller samples.  相似文献   
99.
In a time of budgetary shortfalls in the medical industry, an aging population, and an increased emphasis on health care choices, psychologists are being called upon to administer advance medical directive programs to patients. This study reports preliminary findings from a program to assess and facilitate patients' knowledge of advance directives (ADs) by the Psychology Service at the Ann Arbor VA Medical Center. The participant pool included 243 male veteran patients admitted to medical and surgical wards at the hospital. The intervention included the use of a computer-generated prompt for consultation, which was sent to the psychology staff in response to a patient inquiry regarding ADs. It also involved an increased emphasis on the delivery of written material on ADs by the admissions clerks. The intervention appeared to result in a modest increase in patients' knowledge of advance directives. Suggestions are offered for areas that should be emphasized in future attempts to increase patients' knowledge and utilization of advance directives.  相似文献   
100.
The present experiment attempted to integrate the research on helpfulness in which subjects work for someone else in an artificial laboratory setting (Berkowitz & Daniels, 1963; Berkowitz, 1972) with the bystander-intervention-in-emergencies studies often carried out under more realistic conditions (e.g., Latané & Darley, 1970; Schwartz & Clausen, 1970; Clark & Word, 1972). Fifty-six university women in a 2 × 2 factorial design were led to think they were working for a same-sex peer who could win a cash prize, although there was “nothing in it for them.” Half were told that the other's chance of getting the prize was greatly dependent upon their effort while the remaining participants were informed that the other did not need their-work very much. Moreover, half of the subjects thought they were the only ones working for the other whereas the remaining people believed there were two other co-workers and that the output from all three would be averaged. It was expected that the participants would feel the greatest personal responsibility to help the other and would work hardest for her when she was greatly dependent upon their productivity and they were the only worker, while the subjects would feel the lowest level of personal responsibility for their peer and would be least helpful to her when she was not particularly dependent upon them and there were two other co-workers. The findings are generally in accord with these expectations.  相似文献   
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