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161.
The axiomatic principle that all behavior is choice was incorporated into a revised implementation of an evolutionary theory's account of behavior on single schedules. According to this implementation, target responding occurs in the context of background responding and reinforcement. In Phase 1 of the research, the target responding of artificial organisms (AOs) animated by the revised theory was found to be well described by an exponentiated hyperbola, the parameters of which varied as a function of the background reinforcement rate. In Phase 2, the effect of reinforcer magnitude on the target behavior of the AOs was studied. As in Phase 1, the AOs' behavior was well described by an exponentiated hyperbola, the parameters of which varied with both the target reinforcer magnitude and the background reinforcement rate. Evidence from experiments with live organisms was found to be consistent with the Phase-1 predictions of the revised theory. The Phase-2 predictions have not been tested. The revised implementation of the theory can be used to study the effects of superimposing punishment on single-schedule responding, and it may lead to the discovery of a function that relates response rate to both the rate and magnitude of reinforcement on single schedules. 相似文献
162.
The current research examines how goal orientation affects consumer preference among products with different prices. We argue that a less expensive product may have not only lower perceived quality but also greater perceived quality variability. This greater perceived variability provides the opportunity for optimistic, promotion‐oriented consumers to overestimate the quality of the less expensive product. This effect is weaker, however, for a more expensive product that consumers perceive to have less quality variability and which thus provides less room for quality overestimation. As a result, we hypothesize that promotion‐oriented consumers, as compared to prevention‐oriented consumers, will demonstrate a stronger preference for a less expensive product. In a field study and two laboratory experiments, we obtain empirical support both for the hypothesized effect of consumers’ goal orientation on their product preference and for its underlying process. We conclude with a discussion of the theoretical and practical implications of our results. 相似文献
163.
认知诊断模型选择是认知诊断评估中重要研究问题之一。在实际应用中实践者并不知道真正拟合数据的模型,通常会用模型拟合指标检验模型与数据的拟合程度。从测量结果质量来看,除保证模型与数据拟合之外,还需要重点评价模型诊断结果的信度和效度等。考虑到以往研究大都采用基于信息量的拟合指标去判定模型与数据的匹配性,本研究提出综合考虑模型拟合指标与信度指标用于模型选择或评价模型误设。考虑实验因素为真实模型或分析模型(DINA模型、G-DINA模型、R-RUM模型)、样本量、题量和属性个数,在五因素(3×3×2×2×2)实验设计条件下,比较Bootstrap区间估计的属性分类一致性信度平均数与标准误和常用的拟合统计量-2LL、AIC、BIC对正确模型的选择率。结果表明:-2LL在题目数量多的情况下表现较好,而AIC、BIC在被试量较大的情况下表现较好,在不同的研究条件下,-2LL、AIC、BIC的模型选择率很不稳定,而用Bootstrap法估计的属性分类一致性信度平均数和标准误在不同研究条件的模型选择率较稳定,总体表现较好。 相似文献
164.
When faced with a choice between two aversive events, a person exhibits self-control by choosing a smaller, more immediate aversive event over a larger, delayed aversive event. Task demands are often aversive to children with autism and other developmental disabilities. The purpose of this study was to evaluate behavioral sensitivity to differences in the amount and delay of tasks as part of a preliminary study on self-control. Participants were 2 children with autism who engaged in problem behavior maintained by escape. Results indicated a lack of self-control with respect to choosing between two aversive tasks and suggested potential strategies for increasing self-control (i.e., choosing a small immediate task over a large delayed task). 相似文献
165.
A wealth of data demonstrating that monkeys and apes represent number have been interpreted as suggesting that sensitivity to number emerged early in primate evolution, if not before. Here we examine the numerical capacities of the mongoose lemur (Eulemur mongoz), a member of the prosimian suborder of primates that split from the common ancestor of monkeys, apes and humans approximately 47–54 million years ago. Subjects observed as an experimenter sequentially placed grapes into an opaque bucket. On half of the trials the experimenter placed a subset of the grapes into a false bottom such that they were inaccessible to the lemur. The critical question was whether lemurs would spend more time searching the bucket when food should have remained in the bucket, compared to when they had retrieved all of the food. We found that the amount of time lemurs spent searching was indicative of whether grapes should have remained in the bucket, and furthermore that lemur search time reliably differentiated numerosities that differed by a 1:2 ratio, but not those that differed by a 2:3 or 3:4 ratio. Finally, two control conditions determined that lemurs represented the number of food items, and neither the odor of the grapes, nor the amount of grape (e.g., area) in the bucket. These results suggest that mongoose lemurs have numerical representations that are modulated by Webers Law. 相似文献
166.
In a first study 10 adults, aged 24-44 years, solved all 105 subtraction problems in the form M - N = , where 0 < or = M < or = 13, 0 < or = N < or = 13 and N < or = M. Each participant solved every problem 10 times and in total there were 10 500 answers. Answers, response latencies and errors were registered. Retrospective verbal reports were also given, indicating how a solution was reached: (1) via a (conscious) reconstructive cognitive process or (2) via an (unconscious) reproductive (retrieval) process. The participants made 291 errors (2.8%) when solving the subtractions in study 1. The rate of self-correction was very high, 92%. In a second study 27 undergraduate students estimated overall error rates, including self-corrected errors for the 105 subtraction problems used in the first study. Judged and actual error rates were compared. The participants systematically underestimated error rates for error prone problems and overestimated error rates for error free problems. The participants were fairly accurate when they predicted problems that were most error prone, with a hit rate of 0.67 for the (18) problems predicted as the most error prone ones. In contrast, predictions of which problems were error free were very poor with a hit rate of only 0.20 of the problems predicted as error free really having no errors in study 1. The correlation between judged error rates and frequencies for actually made errors was 0.69 for answers belonging to reconstructive solutions. In contrast, there was no significant correlation between judged and actual error rates at all for retrieved solutions, possibly reflecting the inaccessibility to consciousness of quick retrieval processes. 相似文献
167.
When there exist omitted effects, measurement error, and/or simultaneity in multilevel models, explanatory variables may be
correlated with random components, and standard estimation methods do not provide consistent estimates of model parameters.
This paper introduces estimators that are consistent under such conditions. By employing generalized method of moments (GMM)
estimation techniques in multilevel modeling, the authors present a series of estimators along a robust to efficient continuum.
This continuum depends on the assumptions that the analyst makes regarding the extent of the correlated effects. It is shown
that the GMM approach provides an overarching framework that encompasses well-known estimators such as fixed and random effects
estimators and also provides more options. These GMM estimators can be expressed as instrumental variable (IV) estimators
which enhances their interpretability. Moreover, by exploiting the hierarchical structure of the data, the current technique
does not require additional variables unlike traditional IV methods. Further, statistical tests are developed to compare the
different estimators. A simulation study examines the finite sample properties of the estimators and tests and confirms the
theoretical order of the estimators with respect to their robustness and efficiency. It further shows that not only are regression
coefficients biased, but variance components may be severely underestimated in the presence of correlated effects. Empirical
standard errors are employed as they are less sensitive to correlated effects when compared to model-based standard errors.
An example using student achievement data shows that GMM estimators can be effectively used in a search for the most efficient
among unbiased estimators.
This research was supported by the National Academy of Education/Spencer Foundation and the National Science Foundation, grant
number SES-0436274. We thank the editor, associate editor, and referees for detailed feedback that helped improve the paper. 相似文献
168.
Pere J. Ferrando 《Psychometrika》2007,72(1):25-41
Using Lumsden’s Thurstonian fluctuation model as a starting point, this paper attempts to develop a unidimensional item response
theory model intended for binary personality items. Under some additional assumptions, a new model is obtained in which the
item characteristic curves are defined by a cumulative Pearson-Type-VII distribution, and the person response curves are two-parameter
normal ogives. Procedures for fitting the new model are proposed. Furthermore, the relations between individual fluctuation
and scalability are discussed, and a scalability index based on the new model is proposed. All the developments in this paper
are illustrated using two empirical examples. 相似文献
169.
注意在短时距估计中的作用 总被引:3,自引:0,他引:3
注意一直是时间知觉研究的一个重要问题。本文综述了研究已经取得一些较为一致的结果:在双任务程序中对时间任务的注意越多,时距估计越准确;在单一任务中对目标刺激的时间属性注意越多,对该刺激的持续时距估计越准确;在时间导向任务中,个体可以有效地、主动把注意导向未来的某段时距,那么将对出现在那个时刻的刺激做出更好的反应。最后,讨论了现有研究中存在的、以及今后研究中需要着重考虑的问题。 相似文献
170.
We applied overlapping waves theory and microgenetic methods to examine how children improve their estimation proficiency, and in particular how they shift from reliance on immature to mature representations of numerical magnitude. We also tested the theoretical prediction that feedback on problems on which the discrepancy between two representations is greatest will cause the greatest representational change. Second graders who initially were assessed as relying on an immature representation were presented feedback that varied in degree of discrepancy between the predictions of the mature and immature representations. The most discrepant feedback produced the greatest representational change. The change was strikingly abrupt, often occurring after a single feedback trial, and impressively broad, affecting estimates over the entire range of numbers from 0 to 1000. The findings indicated that cognitive change can occur at the level of an entire representation, rather than always involving a sequence of local repairs. 相似文献