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311.
句子先提述的参与者在可提取性上的优势现象 总被引:6,自引:0,他引:6
下述五个实验就汉语句子成分(包括句子的参与者及其动作)的提述次序对其可提取性的影响进行了研究,结果表明:(1)句子先提述的参与者比后提述的参与者容易被提取,提述的次序对参与者的可提取性有明显影响。(2)先提述参与者的这种优势与句子呈现的方式有一定的关系。(3)在系列呈现的条件下,先提述参与者的易提取性与探测词呈现的延迟间隔有关。(4)在系列呈现的条件下,参与者以名词形式出现时,被试的反应速度较快,而参与者以名字的形式出现时,反应则较慢;在同时呈现的条件下这种差异基本消失。(5)句子参与者的行动(即句子的动词)的提述次序对其可提取性也有明显的影响,说明提述次序对句子成分的可提取性的影响,不只限于句子参与者本身。 相似文献
312.
Rand R. Wilcox 《Psychometrika》1994,59(4):601-616
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
313.
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
314.
The transfer of respondent eliciting and extinction functions through stimulus equivalence classes
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Dougher MJ Augustson E Markham MR Greenway DE Wulfert E 《Journal of the experimental analysis of behavior》1994,62(3):331-351
Two studies investigated the transfer of respondent elicitation through equivalence classes. In Experiment 1, match-to-sample procedures were used to teach 8 subjects two four-member equivalence classes. One member of one class was then paired with electric shock, and one member of the other class was presented without shock. All remaining stimuli were then presented. Using skin conductance as the measure of conditioning, transfer of conditioning was demonstrated in 6 of the 8 subjects. In Experiment 2, similar procedures were used to replicate the results of Experiment 1 and investigate the transfer of extinction. Following equivalence training and conditioning to all members of one class, one member was then presented in extinction. When the remaining stimuli from this class were then presented, they failed to elicit skin conductance. In the final phase of the experiment, the stimulus that was previously presented in extinction was reconditioned. Test trials with other members of the class revealed that they regained elicitation function. These results demonstrate that both respondent elicitation and extinction can transfer through stimulus classes. The clinical and applied significance of the results is discussed. 相似文献
315.
Response acquisition by Siamese fighting fish (Betta splendens) with delayed visual reinforcement 总被引:5,自引:5,他引:0
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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
316.
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
317.
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
318.
319.
Malcolm Ashmore 《Argumentation》1994,8(2):157-161
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
320.