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961.
962.
963.
时序信息提取特点的实验研究 总被引:1,自引:0,他引:1
时距区分性理论认为提取时序信息是在包含一定项目的检索系中检索抽样的过程,通道因素应当对正确率和速度都产生影响.本文分别以英文字母和汉字为材料,对时序信息的提取特点作了两个实验研究.结果表明,只有材料的呈现顺序对时序信息提取的正确率和速度都有影响,通道因素只影响提取的正确率,而速度则未受其影响。显然,用时距区分性理论来说明时序信息提取特点是缺乏足够证据的.本文提出,对时序信息提取机制尚值得进一步研究. 相似文献
964.
Testing the reinforcing properties of S-: a replication of Lieberman''s procedure 总被引:1,自引:1,他引:0 下载免费PDF全文
A critical issue in testing theories of observing is whether the stimulus associated with extinction (the S-) reinforces observing responses. In previous experiments, subjects have been trained to make observing responses that produce both the S- and the stimulus correlated with reinforcement (the S+). Then, either the S+ or the S- has been withheld. Conflicting results have been attributed to differences among species. In the present experiments, pecking one key by master pigeons was reinforced with grain on a variable-ratio extinction schedule. Yoked pigeons received the grain on a variable-interval, extinction schedule controlled by the variable-ratio performances of the master birds. For both groups, concurrent pecking on a second key was reinforced on a variable-interval schedule with displays of discriminative stimuli. Subsequently, either the S+ or the S- was eliminated from the procedure. Omission of S+ produced a large decrease, as predicted by traditional conditioned reinforcement accounts of observing. By itself, S- did not maintain observing. A smaller and less reliable decrease, comparable to that obtained by Lieberman (1972) with rhesus monkeys, occurred when S- was eliminated. This replication with pigeons of Lieberman's results indicates that they are not species-specific, and the fact that observing was not maintained by S- alone suggests that the decrease obtained when S- was omitted is not attributable to the reinforcing power of S-. 相似文献
965.
Several algorithms for covariance structure analysis are considered in addition to the Fletcher-Powell algorithm. These include the Gauss-Newton, Newton-Raphson, Fisher Scoring, and Fletcher-Reeves algorithms. Two methods of estimation are considered, maximum likelihood and weighted least squares. It is shown that the Gauss-Newton algorithm which in standard form produces weighted least squares estimates can, in iteratively reweighted form, produce maximum likelihood estimates as well. Previously unavailable standard error estimates to be used in conjunction with the Fletcher-Reeves algorithm are derived. Finally all the algorithms are applied to a number of maximum likelihood and weighted least squares factor analysis problems to compare the estimates and the standard errors produced. The algorithms appear to give satisfactory estimates but there are serious discrepancies in the standard errors. Because it is robust to poor starting values, converges rapidly and conveniently produces consistent standard errors for both maximum likelihood and weighted least squares problems, the Gauss-Newton algorithm represents an attractive alternative for at least some covariance structure analyses.Work by the first author has been supported in part by Grant No. Da01070 from the U. S. Public Health Service. Work by the second author has been supported in part by Grant No. MCS 77-02121 from the National Science Foundation. 相似文献
966.
Sandra J. Burke 《决策行为杂志》1995,8(4):223-244
This paper demonstrates that choice processing may be different in missing information situations than in full information situations depending on whether inferences are used to fill in missing values and the overlap of the missing information itself. It is shown that when individuals do not form inferences to fill in missing values, fewer full attribute-based processes and more processes which accommodate for missing attribute values, alternative-based or given-dimension attribute-based, are used. It is also shown that when a processing shift due to missing information does occur, the overlap of the missing values will affect the type of shift that takes place. If overlap is high, a shift to given-dimension attribute-based processing is more likely, and when overlap is low, a shift to alternative-based processing is more likely. When individuals do form inferences to fill in missing values, processing is more similar to that in full information situations. Finally, it is shown that individuals will often partially fill in missing information, thus moderating the proposed effects. 相似文献
967.
Gerard J. P. Van Breukelen 《Psychometrika》1995,60(1):95-113
This paper discusses the compatibility of some response time (RT) models with psychometric and with information processing approaches to response times. First, three psychometrically desirable properties of probabilistic models for binary data, related to the principle of specific objectivity, are adapted to the domain of RT models. One of these is the separability of item and subject parameters, and another is double monotonicity. Next, the compatibility of these psychometric properties with one very popular information processing approach, the serial-additive model, is discussed. Finally, five RT models are analyzed with respect to their compatibility with the psychometric properties, with serial-additive processing and with some alternative types of processing. It is concluded that (a) current psychometric models each satisfy one or more of the psychometric properties, but are not (easily) compatible with serial-additive processing, (b) at least one serial-additive processing model satisfies separability of item and subject parameters, and (c) RT models will more easily satisfy double monotonicity than the other two psychometric properties. 相似文献
968.
The purpose of the present study was to investigate the stability of memory and information processing in schizophrenics and affectively disturbed patients. Twenty-two schizophrenics, eight affectives and 14 normal controls were tested twice, with an interval of approximately one year. Results showed that normals performed better than schizophrenics and affectively disturbed patients on almost all of the cognitive measures. The differences reached a level of significance on a reaction time test, a vigilance task and a long-term memory task. The only measure where the difference did not reach a level of significance was on a short-term memory test. Groups' performance to some extent changed over time on most of the measures, but the changes were not significantly different for different groups. 相似文献
969.
项目难度与被试能力分布最优匹配的模拟研究 总被引:2,自引:1,他引:1
该文运用蒙特卡罗方法对被测试能力分布与测验项目难度分布的匹配问题进行模拟分析,分析表明当能力分布为正态分布正偏态分布和负偏态分布时分别与测验项目难度分布与为正态分布,正偏态分布和负偏态分布匹配,比别的匹配有更高测验期望信息值,测验最大信息测验 系数,并且测验信息曲线最大值的能力点与能力分布的众数愈相一致,测验项目参数估计值性真实值的相关也更高。 相似文献
970.
Carolyn M. Jagacinski 《决策行为杂志》1994,7(1):25-42
How do people make evaluations when important items of information are missing? In the context of personnel evaluations or product evaluations, researchers have proposed that decision makers may predict the missing attribute based on its assumed relationship to attributes that are present. In addition, some researchers have suggested that there is a penalty for missing information. An experiment was conducted to investigate the influence of the importance of the missing attribute on the hypothesized inference effect. Hypothetical job candidates were evaluated based on one or two attributes. The correlation between the attributes was varied between groups of subjects as was the importance of one of the attributes. The pattern of ratings of candidates with missing information varied significantly with the correlation condition when the missing attribute was very important, but did not vary as much when the missing attribute was less important. The results were generally consistent with the predictions of the Inferred Information Model (Johnson and Levin, 1985). On average, candidates with missing information were rated lower than comparable candidates with complete information and the missing attribute at an average level. 相似文献