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151.
We investigated how situational (gain–loss), informational (opportunity–threat framing) and dispositional (achievement motive and avoidance motive) variables affected opportunity–threat perception and risky choice in managerial decision-making contexts. In Study 1, the risk preference of the participants showed a reflection effect due to situational differences (gain or loss) and a partial framing effect caused by presenting the same choice information in terms of either opportunities or threats. However, both effects were in the opposite direction of predictions from prospect theory. Gains and positive framing enhanced risk-seeking preference whereas losses and negative framing augmented risk-averse preference. Risk-seeking choices were mediated by opportunity perception whereas risk-averse choices were mediated by threat perception. In Study 2, the participants high in achievement motive perceived greater opportunities in a negative situation, and the participants high in avoidance motive perceived greater threats in a positive situation, suggesting that ambition (achievement motive) operates more significantly in the face of adversities whereas cautiousness (avoidance motive) functions more significantly in prosperity.  相似文献   
152.
Most recent writing linking science and literature has concerned itself with challenges to the epistemological status of scientific knowledge in an attempt to demonstrate its contingency, arguing in the more radical efforts that the structures of science are no more than useful fictions. This essay also includes an epistemological comparison between science and literature, but instead of making grand or meta–statements about the nature of knowing generally in the two fields, mine is a much narrower aim. My exploration entails two tasks. First, I provide a close–up look at a particular type of experiment, called the delayed–choice experiment, which clearly reveals the strangeness of the quantum world. In connection with this experiment, I discuss wave functions—mathematical expressions used by physicists to describe quantum behavior and predict the outcome of experiments involving quanta. Second, I look at Walt Whitman's “Song of Myself” focusing on the meaning of the “self” in the poem. My aim is to treat the object of study in each field as a “text” and to assert and demonstrate a parallel in the strategies of thought and response between physicists (“readers”) pondering the meaning and status of a wave function and poem readers pondering the meaning and status of the poem's self. In Whitman's “Song” we find an attempt to understand complex aspects of human experience that are said to transcend ordinary reality, an effort for which I believe there are parallels in the attempts of modern physicists to understand complex, nonintuitive aspects of the subatomic world. While not making the kind of broad claims eschewed above, I do suggest that this focused study has interesting implications since both the wave function and the poem's self force their respective sets of “readers” to confront questions of ultimacy—to consider, that is, epistemological and ontological issues of more than passing interest to students of science as well as those of metaphysics and theology.  相似文献   
153.
Prior research (cf. Soman & Shi, 2001 ) has shown that obstacles and periods of low progress in an experience reduce the evaluation of that experience. In this research, we propose that the temporal distance between the obstacle and the time of making the evaluation moderates the effect of the obstacle. Consequently, an early (late) obstacle reduces prospective (retrospective) evaluation more significantly than a late (early) obstacle. In two experiments, we find support for this temporal proximity hypothesis. Further, differences between prospective and retrospective evaluations disappeared when the data were analyzed in terms of temporal distance, suggesting that the judgment policies underlying prospective and retrospective evaluations were the same. We also show that it is possible to create pairs of paths such that one of the two paths would be preferred when viewed in prospect, but the other path might be preferred in retrospect. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
154.
This paper examines the occurrence of framing effects when more thought is given to problems. In Study 1, participants were presented with one of two frames of several decision problems. Participants' Need for Cognition (NC) scores were obtained, and half the participants were asked to justify their choices. Substantial framing effects were observed, but the amount of thought purportedly given to a problem, whether manipulated by justification elicitation or measured by NC scores, did not reduce the incidence of framing effects. In Study 2, participants responded to both frames of problems in a within‐subjects design. Again, NC scores were unrelated to responses on the first frame encountered. However, high‐NC, compared to low‐NC, participants were more consistent across frames of a problem. More thought, as indexed here, does not reduce the proclivity to be framed, but does promote adherence to normative principles when the applicability of those principles is detectable. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
155.
New methods were developed for studying risky decision making in children as young as age five. Each child was given a block of ‘gain’ trials, for example, a choice between a sure gain of one prize and a 50:50 chance of gaining either two prizes or no prize, and a block of ‘loss’ trials, for example, a choice between a sure loss of one prize and a 50:50 chance of losing either two prizes or no prize. We were thus able to compare risky choice for gains and losses at the level of the individual child. In each of two experiments a variety of individual difference variables were measured, including in Experiment 2, the child's parent's scores on the same task. Across experiments, the preponderance of choices was of the risky option. However, most children and adults made more risky choices in the domain of losses than in the domain of gains. Predictors of individual differences in children included shyness, impulsivity, and the risk taking of the child's parent. We suggest that methods are now in place to encourage further studies of decision processes in young children. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
156.
The effects of patch encounter rate on patch choice and meal patterns were studied in rats foraging in a laboratory environment offering two patch types that were encountered sequentially and randomly. The cost of procuring access to one patch was greater than the other. Patches were either encountered equally often or the high-cost patch was encountered more frequently. As expected, rats exploited the low-cost patch on almost 100% of encounters and exploited the high-cost patch on a percentage of encounters that was inversely proportional to its cost. Meal size was the same at both patches. Surprisingly, when low-cost patches were rare, the rats did not increase their use of high-cost patches. This resulted in spending more time and energy searching for patches and a higher average cost per meal. The rats responded to this increased cost by reducing the frequency and increasing the size of meals at both patches and thereby limited total daily foraging cost and conserved total intake.  相似文献   
157.
Human subjects were exposed to a concurrent-chains schedule in which reinforcer amounts, delays, or both were varied in the terminal links, and consummatory responses were required to receive points that were later exchangeable for money. Two independent variable-interval 30-s schedules were in effect during the initial links, and delay periods were defined by fixed-time schedules. In Experiment 1, subjects were exposed to three different pairs of reinforcer amounts and delays, and sensitivity to reinforcer amount and delay was determined based on the generalized matching law. The relative responding (choice) of most subjects was more sensitive to reinforcer amount than to reinforcer delay. In Experiment 2, subjects chose between immediate smaller reinforcers and delayed larger reinforcers in five conditions with and without timeout periods that followed a shorter delay, in which reinforcer amounts and delays were combined to make different predictions based on local reinforcement density (i.e., points per delay) or overall reinforcement density (i.e., points per total time). In most conditions, subjects' choices were qualitatively in accord with the predictions from the overall reinforcement density calculated by the ratio of reinforcer amount and total time. Therefore, the overall reinforcement density appears to influence the preference of humans in the present self-control choice situation.  相似文献   
158.
In recent years, choice making has been evaluated as an intervention for people with disabilities. This review examines applied research during the past two decades using choice as a distinct intervention or as part of an intervention package. Fourteen studies published between 1975 and 1996 were identified that implemented choice as an intervention to increase or decrease a target behavior. These studies applied choice-making in the following three broad areas: (a) vocational or domestic activities; (b) academic activities; and (c) leisure, recreational, or social activities. All of the studies indicated that choice-making procedures resulted in behavioral improvements with some, if not all of the participants.  相似文献   
159.
In Experiment 1, pigeons' pecks on a green key led to a 5-s delay with green houselights, and then food was delivered on 20% (or, in other conditions, 50%) of the trials. Pecks on a red key led to an adjusting delay with red houselights, and then food was delivered on every trial. The adjusting delay was used to estimate indifference points: delays at which the two alternatives were chosen about equally often. Varying the presence or absence of green houselights during the delays that preceded possible food deliveries had large effects on choice. In contrast, varying the presence of the green or red houselights in the intertrial intervals had no effects on choice. In Experiment 2, pecks on the green key led to delays of either 5 s or 30 s with green houselights, and then food was delivered on 20% of the trials. Varying the duration of the green houselights on nonreinforced trials had no effect on choice. The results suggest that the green houselights served as a conditioned reinforcer at some times but not at others, depending on whether or not there was a possibility that a primary reinforcer might be delivered. Given this interpretation of what constitutes a conditioned reinforcer, most of the results were consistent with the view that the strength of a conditioned reinforcer is inversely related to its duration.  相似文献   
160.
Group choice: competition, travel, and the ideal free distribution   总被引:5,自引:4,他引:1       下载免费PDF全文
If a group of foragers distributes among resource patches according to the ideal free distribution, the relative number of foragers in each patch should match the relative amount of resource obtained there, unless deviations arise from factors such as incomplete information or interforager interference. In analogy to individual choice, such effects may produce undermatching—group distribution falling short of resource distribution—or overmatching—group distribution overshooting resource distribution. In the present experiments, a flock of about 30 pigeons distributed between two patches with continuous inputs of green peas. Competition was varied by changing the size or extent of the patches. When the patches were areas or troughs, some undermatching occurred. When the patches were small bowls, strong undermatching occurred. When travel was required to switch patches, undermatching decreased slightly. A visual barrier that prevented pigeons from seeing one patch from the other had no effect. Overall rate of food delivery, varied over a wide range, had no effect. It appeared that the mechanism of flock distribution depended on comparisons between patches that were successive rather than simultaneous. Although most pigeons participated in the experiments, and different pigeons participated to different extents, individual pigeons tended to be consistent in the extent of participation from session to session, suggesting the possibility that participation might reflect competitive ability. Examination of the preferences and switching of individual pigeons revealed no consistency within or across individuals. It appeared that the flock's distribution was a truly emergent phenomenon, in the sense that results at the level of the flock in no way paralleled behavior at the level of the individual.  相似文献   
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