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211.
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This paper spells out a dynamic proof format for the pure logic of relevant implication. (A proof is dynamic if a formula derived at some stage need not be derived at a later stage.) The paper illustrates three interesting points. (i) A set of properties that characterizes an inference relation on the (very natural) dynamic proof interpretation, need not characterize the same inference relation (or even any inference relation) on the usual set-theoretical interpretation. (ii) A proof format may display an internal dynamics (defeasible conclusions) in the absence of an external dynamics (non-monotonicity). (iii) A monotonic logic may have a non-monotonic characterization. 相似文献
213.
In the standard money pump, an agent with cyclical preferences can avoid exploitation if he shows foresight and solves his sequential decision problem using backward induction (BI). This way out is foreclosed in a modified money pump, which has been presented in Rabinowicz (2000). There, BI will lead the agent to behave in a self-defeating way. The present paper describes another sequential decision problem of this kind, the Centipede for an Intransitive Preferrer, which in some respects is even more striking than the modified pump. In the new problem, the BI reasoning that implies self-defeating behavior does not rest on the controversial robustness assumption concerning beliefs in one's future rationality. This strengthens the claim that foresight cannot save the intransitive preferrer from a self-defeating course of action. 相似文献
214.
认知匹配策略和形式匹配策略的实验研究 总被引:7,自引:0,他引:7
将用以调节学生学习心向的两条教材内容的情感性处理策略——认知匹配策略和形式匹配策略分别运用于语文和外语教学中,进行现场教学实验研究。研究结果表明:分别运用这两条策略对教材内容进行情感性处理,对调节学生的学习心向,促进学生的认知和情感学习、提高课堂教学质量是可行而有效的。 相似文献
215.
小学儿童假设检验思维策略的发展 总被引:2,自引:0,他引:2
采用自创的“固定样例”程序,利用自行设计的两种不同任务的图形推理材料,研究了小学儿童假设检验策略的发展。550名不同年级的被试参加了本研究:结果发现,在该研究条件下:(1)答案存在多种可能性的任务Ⅰ明显难于答案确定的任务Ⅱ;(2)小学儿童假设检验能力随年级提高而增长,但增长的速度因任务不同而不同;(3)随着年级的提高,小学儿童使用的不成功策略逐步下降,成功策略显著上升,但这也受任务不同的影响;(4)固定样例程序较好地克服了变化样例程序所带来的假设检验研究的缺陷。 相似文献
216.
幼儿对数的认知及其策略 总被引:7,自引:0,他引:7
该研究探查幼儿对基数、数序、运算和解应用题的认知发展过程及其认知策略。着重探查:(1)不同认知任务对幼儿数认知发展的影响;(2)幼儿对基数和数序两者认知发展的顺序;(3)从幼儿主动解决问题的策略探究其认知发展水平。该研究采用定性和定量相结合的研究方法。被试为4、5、6岁城市幼儿园儿童,共92人,男女约各半。全部实验以个别方式进行。主要研究结果表明:(1)幼儿对基数、数序、运算和解应用题的认知成绩均有随年龄发展的趋势,但快速发展的年龄阶段因任务的难度而异;(2)幼儿对基数和数序的认知在4—5岁显示出不同步的发展,对基数的认知成绩优于对数序的认知,而到6岁两者具有同步发展的趋势;(3)幼儿解决问题的策略水平随年龄发展,显示了由外化水平的智力活动向完全内化的智力操作的发展过程,并具有明显的层次性。该研究结果为幼儿数能力的培养和促进提供参考依据。 相似文献
217.
218.
A dynamic factor model is proposed for the analysis of multivariate nonstationary time series in the time domain. The nonstationarity in the series is represented by a linear time dependent mean function. This mild form of nonstationarity is often relevant in analyzing socio-economic time series met in practice. Through the use of an extended version of Molenaar's stationary dynamic factor analysis method, the effect of nonstationarity on the latent factor series is incorporated in the dynamic nonstationary factor model (DNFM). It is shown that the estimation of the unknown parameters in this model can be easily carried out by reformulating the DNFM as a covariance structure model and adopting the ML algorithm proposed by Jöreskog. Furthermore, an empirical example is given to demonstrate the usefulness of the proposed DNFM and the analysis. 相似文献
219.
JUNJI KOMAKI 《The Japanese psychological research》1996,38(3):156-162
Abstract: Three groups of male adult Japanese monkeys were trained in 30 discrimination-reversal learning-set (LS) problems using the Wisconsin General Test Apparatus. A control group ( N = 3) was trained in the standard procedure: acquisition of up to 12 consecutive correct responses, reversal to the same criterion, and then shift to a new problem. To the other two groups, three information trials signaling the stimulus value in reversal were given after they reached the criterion in acquisition. Subjects in the positive-stimulus information (PSI) group ( N = 4) were exposed only to the reversal positive stimulus, and a response to it was rewarded. Subjects in the negative-stimulus information (NSI) group ( N = 4) were exposed only to the reversal negative stimulus, and any response to it was not rewarded. Information trials reduced reversal errors and NSI trials were more effective than PSI trials in error reduction ( p < .05). Information trials also aided in acquisition: the NSI and PSI groups learned the acquisition phase of the problems with significantly fewer errors than control group ( p < .01) in the last stage of training. The implications of these results are discussed in relation to strategy learning and attention learning in LS formation. 相似文献
220.
题材个体化和问题重述两策略的效果研究 总被引:1,自引:0,他引:1
探讨题材个体化和问题重述作为两种解题策略在解决加、减法应用题中的有效性,采用了4种策略类型×3种数学能力水平×2种问题题材×2种题材情境与解题操作关系的四因素混合设计。结论如下:学生基本上能够独立进行题材个体化和问题重述;在本实验条件下,水平高的学生,运用不同策略没有差异;水平中等的学生运用双策略、水平低的学生运用双策略以及题材个体化策略均产生了积极效果;题材个体化策略对于解决不熟悉题材的应用题将产生积极效果,运用以上两策略解决问题情境与解题操作相矛盾的问题没有帮助。除了应用题陈述图式以外,本实验证明还存在着应用题结构图式;可把题材个体化和问题重述作为解题策略教给学生运用。 相似文献