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251.
小学儿童奖赏公平性的认知发展   总被引:2,自引:0,他引:2  
方富熹  王文忠 《心理学报》1994,27(4):354-361
采用信息加工研究途径并假设故事情境探索小学儿童对奖赏公平性的社会认知发展,并将儿童的发展与成人作对比。研究结果表明,7,9岁儿童容易将"均等"与"公平"混淆,还没形成一个稳定的分配模式,而12岁儿童已能运用"努力"、"成果"、"能力"等规则较为稳定地作出公平奖赏决定或评价,但还没达到对更高层次的社会准则的理解和掌握。儿童这一发展制约于他们的信息加工能力以及获得有关社会价值观的社会化过程。  相似文献   
252.
A well-known result is that the usual correlation coefficient,, is highly nonrobust: very slight changes in only one of the marginal distributions can alter by a substantial amount. There are a variety of methods for correcting this problem. This paper identifies one particular method which is useful in psychometrics and provides a simple test for independence. It is not recommended that the new test replace the usual test ofH 0: = 0, but the new test has important advantages over the usual test in terms of both Type I errors and power.  相似文献   
253.
The partial credit model is considered under the assumption of a certain linear decomposition of the item × category parameters ih into basic parameters j. This model is referred to as the linear partial credit model. A conditional maximum likelihood algorithm for estimation of the j is presented, based on (a) recurrences for the combinatorial functions involved, and (b) using a quasi-Newton approach, the so-called Broyden-Fletcher-Goldfarb-Shanno (BFGS) method; (a) guarantees numerically stable results, (b) avoids the direct computation of the Hesse matrix, yet produces a sequence of certain positive definite matricesB k ,k=1, 2, ..., converging to the asymptotic variance-covariance matrix of the . The practicality of these numerical methods is demonstrated both by means of simulations and of an empirical application to the measurement of treatment effects in patients with psychosomatic disorders.The authors thank one anonymous reviewer for his constructive comments. Moreover, they thankfully acknowledge financial support by the Österreichische Nationalbank (Austrian National Bank) under Grant No. 3720.  相似文献   
254.
Male Siamese fighting fish, Betta splendens, swam through a ring in an aquarium, breaking a photocell beam and initiating an unsignaled, resetting delay interval. Following delays of 0 s, 10 s, or 25 s, a 15-s mirror presentation released an aggressive display by the fish. Swimming through the ring increased in the absence of either a period of acclimatization to the reinforcer (analogous to magazine training when appetitive reinforcers are used) or explicit training of the response by the experimenters. Response rates were a decreasing function of delay duration. Other fish exposed to a schedule of response-independent mirror presentations failed to acquire and maintain the response. The results demonstrate the robustness and generality of the phenomenon of response acquisition with delayed reinforcement. They further qualify earlier observations about behavioral mechanisms involved in the phenomenon.  相似文献   
255.
Operant temporal discrimination learning was investigated in goldfish. In the first experiment, there was a fixed daily change in illumination. Eight subjects were trained to operate a lever that reinforced each press with food. The period during which responses were reinforced was then progressively reduced until it was 1 hr in every 24. The final 1-hr feeding schedule was maintained over 4 weeks. The feeding period commenced at the same time each day throughout. The food dispensers were then made inactive, and a period of extinction ensued for 6 days. The pattern of responding suggested that the fish were able to exhibit temporal discrimination in anticipation of feeding time. This pattern of responding persisted for a limited number of days during the extinction procedure. The second experiment produced evidence that operant temporal discrimination could develop under continuous illumination.  相似文献   
256.
Exchange delays and impulsive choice in adult humans.   总被引:4,自引:3,他引:1       下载免费PDF全文
Choice responding by adult humans in a discrete-trial task was examined as a function of conditions that manipulated either the delay to point delivery or the delay between points and their exchange for money. In point-delay conditions, subjects chose between an "impulsive" alternative that provided a small amount of points immediately and a "self-control" alternative that provided a larger amount of points delayed by 15, 30, or 60 s. Points were exchanged for money immediately following the session. Subjects preferred the self-control alternative. In exchange-delay conditions, subjects chose between a small amount of points exchangeable for money immediately following the session and a larger amount of points exchangeable for money after 1 day, 3 weeks, or 6 weeks. A self-control preference observed for all subjects in the 1-day exchange-delay condition reversed to exclusive impulsive preference for 4 of the 6 subjects when choice conditions involved exchange delays of 3 or 6 weeks. These results show that human choice is sensitive to the manipulation of exchange delays and that impulsive preference can be obtained with exchange delays on the order of weeks.  相似文献   
257.
258.
This essay argues that the really useful character of reflexivity is that it enables a radical critique of representation and its conventional material and rhetorical practices. It is uniquely able to produce paradox and thus disrupt discourses by undermining authorial privilege. Because Fuller's social epistemology is insensitive to its own reflexive implications, and limits itself to normative questions about knowledge policy, it is too limited — and limiting — to provide a context that can nurture reflexivity.  相似文献   
259.
260.
This study assesses the impact of accountability, the status quo, and anticipated costs and benefits on judgement of the acceptability of a drug in the US pharmaceuticals market. Several effects are documented: (1) subjects were more accepting of a drug, the lower the anticipated risks of side effects and the greater the anticipated benefits; (2) subjects were especially unwilling to accept risk when the drug was not yet on the market and when they felt accountable for their decisions; (3) accountable subjects confronted by an off-the-market drug that posed moderate or high risk were also especially likely to procrastinate, to buckpass, and to think in integratively complex ways about the problem, notwithstanding the fact that many more lives would be saved than lost. We explain these results by positing that perceptual-cognitive processes (loss aversion) and political processes (blame avoidance) mutually reinforce each other when decision makers are accountable for choices that raise the possibility of changing the status quo in ways that impose losses on identifiable constituencies. We conclude by commenting on the complex normative issues that arise in labelling response tendencies as biases. Choices that look irrational within one ethical or political framework sometimes appear quite reasonable with another.  相似文献   
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