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91.
Tucker3 hierarchical classes analysis   总被引:1,自引:0,他引:1  
This paper presents a new model for binary three-way three-mode data, called Tucker3 hierarchical classes model (Tucker3-HICLAS). This new model generalizes Leenen, Van Mechelen, De Boeck, and Rosenberg's (1999) individual differences hierarchical classes model (INDCLAS). Like the INDCLAS model, the Tucker3-HICLAS model includes a hierarchical classification of the elements of each mode, and a linking structure among the three hierarchies. Unlike INDCLAS, Tucker3-HICLAS (a) does not restrict the hierarchical classifications of the three modes to have the same rank, and (b) allows for more complex linking structures among the three hierarchies. An algorithm to fit the Tucker3-HICLAS model is described and evaluated in an extensive simulation study. An application of the model to hostility data is discussed.The first author is a Research Assistant of the Fund for Scientific Research-Flanders (Belgium). The research reported in this paper was partially supported by the Research Council of K.U. Leuven (GOA/2000/02). We are grateful to Kristof Vansteelandt for providing us with an interesting data set.  相似文献   
92.
This study examined demographic characteristics, social competence, and behavior problems in clinic-referred children with gender identity problems in Toronto, Canada (N = 358), and Utrecht, The Netherlands (N = 130). The Toronto sample was, on average, about a year younger than the Utrecht sample at referral, had a higher percentage of boys, had a higher mean IQ, and was less likely to be living with both parents. On the Child Behavior Checklist (CBCL), both groups showed, on average, clinical range scores in both social competence and behavior problems. A CBCL-derived measure of poor peer relations showed that boys in both clinics had worse ratings than did the girls. A multiple regression analysis showed that poor peer relations were the strongest predictor of behavior problems in both samples. This study—the first cross-national, cross-clinic comparative analysis of children with gender identity disorder—found far more similarities than differences in both social competence and behavior problems. The most salient demographic difference was age at referral. Cross-national differences in factors that might influence referral patterns are discussed.  相似文献   
93.
This paper informally summarizes a two-day symposium held at the U.S. National Academy of Sciences in Washington, D.C., September 5–6, 2002. The issue was to what extent the progress of science and societal capacity for continued technological innovation are threatened by excessive protection of intellectual property. Excessive protection creates disadvantages not only for scientists and inventors but also for educators/students and for librarians/clientele. Speakers from a variety of disciplines and institutions agreed unanimously that scientific and technological progress is, indeed, under serious threat. Various opinions were expressed about the degree of threat, currently and prospectively, as well as what counter-measures are best suited to resist undue restrictions on creative uses of scientific and technical data and information. This summary is based entirely on the author’s notes from the symposium, and the commentary offered is his alone. My apologies to the speakers if this paper does not accurately reflect the primary intent of their presentations. The “Suggested Readings” offered at the end are not specific to the speakers’ statements but rather are offered as a general resource to aid further research. The definitive record of the symposium is planned to be available from the National Academies Press as a Proceedings publication in the summer of 2003. John Gardenier is an independent researcher, ethicist and science writer.  相似文献   
94.
In this paper, the constrained maximum likelihood estimation of a two-level covariance structure model with unbalanced designs is considered. The two-level model is reformulated as a single-level model by treating the group level latent random vectors as hypothetical missing-data. Then, the popular EM algorithm is extended to obtain the constrained maximum likelihood estimates. For general nonlinear constraints, the multiplier method is used at theM-step to find the constrained minimum of the conditional expectation. An accelerated EM gradient procedure is derived to handle linear constraints. The empirical performance of the proposed EM type algorithms is illustrated by some artifical and real examples.This research was supported by a Hong Kong UCG Earmarked Grant, CUHK 4026/97H. We are greatly indebted to D.E. Morisky and J.A. Stein for the use of their AIDS data in our example. We also thank the Editor, two anonymous reviewers, W.Y. Poon and H.T. Zhu for constructive suggestions and comments in improving the paper. The assistance of Michael K.H. Leung and Esther L.S. Tam is gratefully acknowledged.  相似文献   
95.
Although structural priming has been considered to be an independent cognitive process, recent evidence suggests that structural priming is modulated by sociocognitive factors such as social perception; speakers are more likely to mimic the sentence structure of a socially desirable interlocutor than the structure of a less desirable interlocutor. This study aims to further address the role of sociocognitive factors in language use by investigating how individual differences in social perception and tendency to align with others (i.e., social monitoring) modulate same‐verb structural priming. In particular, we investigate how likely students are to repeat a sentence structure of a teacher depending on their perception of the teacher and their social monitoring tendency. Our results demonstrate that students’ tendency to imitate a sentence structure of the teacher is positively influenced by their perception of the teacher but negatively by social monitoring. We suggest that the effects may be accounted for in terms of their influence on attention and memory encoding.  相似文献   
96.
Objective: The authors attempted to develop and validate a general distress index for a multidimensional psychological symptom/outcome measure used in over 300 college counseling centers with more than 100,000 cases annually: the Counseling Center Assessment of Psychological Symptoms (CCAPS). Method: Four models were compared for fit indices (n = 19,247): the existing first-order factor model (without a general factor), a second-order factor model, a bifactor model, and a single factor or “total score” model. In separate clinical and non-clinical samples, concurrent and divergent validity were examined using several well-established measures of psychological symptoms, as well as two-week test–retest and treatment utilization data. Results: Second-order and bifactor models which captured a single “distress” factor both exhibited good fit to the data relative to the baseline and “total score” model. Validity data indicated that factors adequately measured meaningful clinical onstructs. Conclusion: Both the bifactor and second-order models indicated the presence of a “distress index” comprised items across many of the CCAPS subscales. This distress scale has strong applicability for benchmarking the overall severity and complexity of patients at different centers, and can be used to help identify colleges and universities with areas of clinical strength, which can be studied to improve the field. Clinically, the distress index offers a parsimonious and efficient method for clinicians to monitor patients’ progress through treatment.  相似文献   
97.
We used the take‐the‐best heuristic to develop a model to forecast the popular two‐party vote shares in U.S. presidential elections. The model draws upon information about how voters expect the candidates to deal with the most important issue facing the country. We used cross‐validation to calculate a total of 1000 out‐of‐sample forecasts, one for each of the last 100 days of the ten U.S. presidential elections from 1972 to 2008. Ninety‐seven per cent of forecasts correctly predicted the winner of the popular vote. The model forecasts were competitive compared to forecasts from methods that incorporate substantially more information (e.g., econometric models and the Iowa Electronic Markets). The purpose of the model is to provide fast advice on which issues candidates should stress in their campaign. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
98.
The commentary discusses several topics in Dr. Iacobucci's article on mediation analysis with categorical variables including the lack of equivalency of mediated effect measures, ab, and cc′, that are algebraically equivalent in ordinary least squares regression models. The commentary raises the issue of correlated mediation coefficients and presents formulas to include the correlation in the test of significance. References to new developments in causal mediation analysis for categorical variables are given and the importance of programs of research to establish a mediation theory is emphasized.  相似文献   
99.
This paper provides an overview and task analysis for creating a continuous ABC data‐collection application using Xcode on a Mac computer. Behavior analysts can program an ABC data collection system, complete with a customized list of target clients, antecedents, behaviors, and consequences to be recorded, and have the data automatically sent to an e‐mail account after observations have concluded. Further suggestions are provided to customize the ABC data‐ collection system for individual preferences and clinical needs.  相似文献   
100.
This study examined the effects of text messaging class arrival to an academic counselor on the attendance and punctuality of 4 college student athletes. Each participant had a history of class tardiness and was considered to be at risk for academic failure. Class attendance and punctuality improved for all participants.  相似文献   
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