首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   384篇
  免费   3篇
  2023年   3篇
  2022年   1篇
  2021年   2篇
  2020年   3篇
  2019年   2篇
  2018年   7篇
  2017年   3篇
  2016年   4篇
  2015年   4篇
  2014年   6篇
  2013年   40篇
  2012年   16篇
  2011年   23篇
  2010年   14篇
  2009年   17篇
  2008年   18篇
  2007年   16篇
  2006年   19篇
  2005年   20篇
  2004年   15篇
  2003年   13篇
  2002年   10篇
  2001年   9篇
  2000年   8篇
  1999年   10篇
  1998年   5篇
  1997年   7篇
  1996年   6篇
  1995年   5篇
  1994年   7篇
  1993年   7篇
  1992年   11篇
  1991年   7篇
  1990年   6篇
  1989年   8篇
  1988年   5篇
  1987年   5篇
  1986年   2篇
  1985年   4篇
  1984年   4篇
  1982年   4篇
  1981年   1篇
  1979年   1篇
  1978年   3篇
  1976年   1篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
  1971年   2篇
排序方式: 共有387条查询结果,搜索用时 15 毫秒
311.
Three-Mode Factor Analysis (3MFA) and PARAFAC are methods to describe three-way data. Both methods employ models with components for the three modes of a three-way array; the 3MFA model also uses a three-way core array for linking all components to each other. The use of the core array makes the 3MFA model more general than the PARAFAC model (thus allowing a better fit), but also more complicated. Moreover, in the 3MFA model the components are not uniquely determined, and it seems hard to choose among all possible solutions. A particularly interesting feature of the PARAFAC model is that it does give unique components. The present paper introduces a class of 3MFA models in between 3MFA and PARAFAC that share the good properties of the 3MFA model and the PARAFAC model: They fit (almost) as well as the 3MFA model, they are relatively simple and they have the same uniqueness properties as the PARAFAC model.This research has been made possible by a fellowship from the Royal Netherlands Academy of Arts and Sciences to the first author. Part of this research has been presented at the first conference on ThRee-way methods In Chemistry (TRIC), a meeting of Psychometrics and Chemometrics, Epe, The Netherlands, August 1993. The authors are obliged to Age Smilde for stimulating this research, and two anonymous reviewers for many helpful suggestions.  相似文献   
312.
Weighted least squares fitting using ordinary least squares algorithms   总被引:2,自引:0,他引:2  
A general approach for fitting a model to a data matrix by weighted least squares (WLS) is studied. This approach consists of iteratively performing (steps of) existing algorithms for ordinary least squares (OLS) fitting of the same model. The approach is based on minimizing a function that majorizes the WLS loss function. The generality of the approach implies that, for every model for which an OLS fitting algorithm is available, the present approach yields a WLS fitting algorithm. In the special case where the WLS weight matrix is binary, the approach reduces to missing data imputation.This research has been made possible by a fellowship from the Royal Netherlands Academy of Arts and Sciences to the author.  相似文献   
313.
Brokken has proposed a method for orthogonal rotation of one matrix such that its columns have a maximal sum of congruences with the columns of a target matrix. This method employs an algorithm for which convergence from every starting point is not guaranteed. In the present paper, an iterative majorization algorithm is proposed which is guaranteed to converge from every starting point. Specifically, it is proven that the function value converges monotonically, and that the difference between subsequent iterates converges to zero. In addition to the better convergence properties, another advantage of the present algorithm over Brokken's one is that it is easier to program. The algorithms are compared on 80 simulated data sets, and it turned out that the new algorithm performed well in all cases, whereas Brokken's algorithm failed in almost half the cases. The derivation of the algorithm is given in full detail because it involves a series of inequalities that can be of use to derive similar algorithms in different contexts.This research has been made possible by a fellowship from the Royal Netherlands Academy of Arts and Sciences to the first author. The authors are obliged to Willem J. Heiser and Jos M. F. ten Berge for useful comments on an earlier version of this paper.  相似文献   
314.
315.
316.
Results of functional analysis were ambiguous in suggesting that self-injurious behavior (SIB) was maintained by escape, sensory reinforcement, or both. To help clarify these results, we compared escape extinction, sensory extinction, and the combined treatments. Sensory extinction proved to be a necessary and sufficient treatment, whereas escape extinction failed to decrease SIB. These analyses helped to clarify the function of SIB and to identify an effective and efficient treatment.  相似文献   
317.
Visser  Henk 《Synthese》1999,119(1-2):135-156
Emphasis in historiography of science is naturally placed on the discoveries and inventions which scientists make and generally less on new methods of doing science, but sometimes the latter can he an important clue to help us understand the former. For example, while we all acknowledge how great the contributions of Maxwell, Boltzmann, Planck, and Einstein were to physics from roughly 1870 to 1920, we often overlook the significance of a methodological phrase which was popular during that same period, namely, what in German was called “Bildtheorie” or in English “picture theory”. But even before we can properly study its significance we have to know what the theory was, but even this presents problems, since the meaning changed. In fact, this paper is an attempt not only to describe the history of that change from Maxwell to Wittgenstein but to study in particular how Boltzmann’s conception of Bildtheorie seems to have been at least partly incorporated into the approach of Ludwig Wittgenstein. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
318.
A loglinear IRT model is proposed that relates polytomously scored item responses to a multidimensional latent space. The analyst may specify a response function for each response, indicating which latent abilities are necessary to arrive at that response. Each item may have a different number of response categories, so that free response items are more easily analyzed. Conditional maximum likelihood estimates are derived and the models may be tested generally or against alternative loglinear IRT models.Hank Kelderman is currently affiliated with Vrije Universiteit, Amsterdam.We thank Linda Vodegel-Matzen of the Division of Developmental Psychology of the University of Amsterdam for making available the data used in the example in this article.  相似文献   
319.
Kroonenberg and de Leeuw have suggested fitting the IDIOSCAL model by the TUCKALS2 algorithm for three-way components analysis. In theory, this is problematic because TUCKALS2 produces two possibly different coordinate matrices, that are useless for IDIOSCAL unless they are equal. Kroonenberg has claimed that, when IDIOSCAL is fitted by TUCKALS2, the resulting coordinate matrices will be identical. In the present paper, this claim is proven valid when the data matrices are semidefinite. However, counterexamples for indefinite matrices are also constructed, by examining the global minimum in the case where the data matrices have the same eigenvectors. Similar counterexamples have been considered by ten Berge and Kiers in the related context of CANDECOMP/PARAFAC to fit the INDSCAL model.  相似文献   
320.
In three experiments, the meaning activation of ambiguous nouns in novel nominal compounds was investigated. Ambiguous nouns were unbalanced homographs occurring as the second members of the compound. Meaningful interpretations of the compounds were based on either the dominant or the subordinate meaning of the ambiguous noun. In Experiment 1, visually presented novel compounds serving as primes were followed at varying intervals by targets associatively related to distinct meanings of the ambiguous noun. In a lexical decision task, facilitation effects were found only for targets related to the meaning that was relevant for the interpretation of the compound. Experiment 2 showed that interactive activation could not be attributed to differences in semantic relatedness between the first members of compounds and targets. Experiment 3 demonstrated equal intralexical relatedness between members for both types of compounds. It is proposed that interactive activation may facilitate the interpretation of the novel compound. Compatible meaning aspects of the nouns may become more strongly activated, and incompatible meaning aspects may not become activated. The selection of meaning aspects relevant for interpretation would thereby be simplified.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号