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   34305篇
  免费   1185篇
  国内免费   11篇
  35501篇
  2018年   463篇
  2017年   513篇
  2016年   565篇
  2015年   404篇
  2014年   504篇
  2013年   2784篇
  2012年   872篇
  2011年   975篇
  2010年   667篇
  2009年   619篇
  2008年   927篇
  2007年   909篇
  2006年   881篇
  2005年   768篇
  2004年   746篇
  2003年   761篇
  2002年   779篇
  2001年   776篇
  2000年   793篇
  1999年   635篇
  1998年   409篇
  1997年   412篇
  1996年   409篇
  1995年   386篇
  1992年   612篇
  1991年   569篇
  1990年   554篇
  1989年   525篇
  1988年   541篇
  1987年   521篇
  1986年   564篇
  1985年   552篇
  1984年   505篇
  1983年   472篇
  1982年   406篇
  1981年   419篇
  1979年   511篇
  1978年   473篇
  1977年   423篇
  1976年   422篇
  1975年   464篇
  1974年   558篇
  1973年   584篇
  1972年   434篇
  1971年   430篇
  1970年   394篇
  1969年   423篇
  1968年   496篇
  1967年   439篇
  1966年   462篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
In a comparison of religious and nonreligious psychotherapists' perceptions of a portion of a psychotherapeutic session no significant differences were found on the Vanderbilt Psychotherapy Process Scale for four groups of therapists designated according to their scores on three religious questionnaires. While the results suggest attitudes toward religion are not reflected in therapists' practice of psychotherapy, limitations of the study indicate the need for more rigorous testing of this possibility.  相似文献   
942.
The many null distributions of person fit indices   总被引:1,自引:0,他引:1  
This paper deals with the situation of an investigator who has collected the scores ofn persons to a set ofk dichotomous items, and wants to investigate whether the answers of all respondents are compatible with the one parameter logistic test model of Rasch. Contrary to the standard analysis of the Rasch model, where all persons are kept in the analysis and badly fittingitems may be removed, this paper studies the alternative model in which a small minority ofpersons has an answer strategy not described by the Rasch model. Such persons are called anomalous or aberrant. From the response vectors consisting ofk symbols each equal to 0 or 1, it is desired to classify each respondent as either anomalous or as conforming to the model. As this model is probabilistic, such a classification will possibly involve false positives and false negatives. Both for the Rasch model and for other item response models, the literature contains several proposals for a person fit index, which expresses for each individual the plausibility that his/her behavior follows the model. The present paper argues that such indices can only provide a satisfactory solution to the classification problem if their statistical distribution is known under the null hypothesis that all persons answer according to the model. This distribution, however, turns out to be rather different for different values of the person's latent trait value. This value will be called ability parameter, although our results are equally valid for Rasch scales measuring other attributes.As the true ability parameter is unknown, one can only use its estimate in order to obtain an estimated person fit value and an estimated null hypothesis distribution. The paper describes three specifications for the latter: assuming that the true ability equals its estimate, integrating across the ability distribution assumed for the population, and conditioning on the total score, which is in the Rasch model the sufficient statistic for the ability parameter.Classification rules for aberrance will be worked out for each of the three specifications. Depending on test length, item parameters and desired accuracy, they are based on the exact distribution, its Monte Carlo estimate and a new and promising approximation based on the moments of the person fit statistic. Results for the likelihood person fit statistic are given in detail, the methods could also be applied to other fit statistics. A comparison of the three specifications results in the recommendation to condition on the total score, as this avoids some problems of interpretation that affect the other two specifications.The authors express their gratitude to the reviewers and to many colleagues for comments on an earlier version.  相似文献   
943.
A highly systematic relation between the conditional probability of recognition given recall and the overall recognition hit rate has been demonstrated in a wide variety of experiments. A function describing this relationship was developed by Tulving & Wiseman (1975). Exceptions to this function have, in retrospect, been interpreted in terms of (a) a low integration between cue and target items, or (b) a high cue overlap between the two tests involved: recognition and recall. The experiment reported was designed to evaluate the joint and the separate contributions from integration and cue overlap for obtaining conformity with and exception from the Tulving-Wiseman function. In line with the predictions made, the results showed that these two factors in combination can account for data that fit the function and for exceptions above the function. In relative terms, the contribution from integration was somewhat more pronounced than that from cue overlap.  相似文献   
944.
A model is presented for item responses when different subjects employ different strategies, but only responses, not choice of strategy, can be observed. Using substantive theory to differentiate the likelihoods of response vectors under a fixed set of strategies, we model response probabilities in terms of item parameters for each strategy, proportions of subjects employing each strategy, and distributions of subject proficiency within strategies. The probabilities that an individual subject employed the various strategies can then be obtained, along with a conditional estimate of proficiency under each. A conceptual example discusses response strategies for spatial rotation tasks, and a numerican example resolves a population of subjects into subpopulations of valid responders and random guessers.The first author's work was supported by Contract No. N00014-85-K-0683, project designation NR 150-539, from the Cognitive Science Program, Cognitive and Neural Sciences Division, Office of Naval Research. We are grateful to Murray Aitkin, Isaac Bejar, Neil Dorans, Frederiksen, and Marklyn Wingersky for their comments and suggestions, and to Alison Gooding, Maxine Kingston, Donna Lembeck, Joling Liang, and Kentaro Yamamoto for their assistance with Example 2.  相似文献   
945.
Converging operations on a basic level in event taxonomies   总被引:1,自引:0,他引:1  
Research on object concepts has identified one level of abstraction as "basic" in cognition and communication. We investigated whether concepts for routine social events have a basic level by replicating the converging operations used to investigate object concepts. In Experiment 1, subjects were presented with event names from a taxonomy and were asked to list the actions comprising the event. Many more actions were listed at the middle than at the highest taxonomic level, without a further increase at the most specific level, paralleling the pattern of superordinate-, basic-, and subordinate-level object concepts. From these action lists, brief stories were composed for each event. In Experiment 2, subjects made pairwise similarity judgments on the stories. The mean similarity of events increased with specificity, as expected. But differentiation of categories (within-category similarity compared to between-category similarity) was highest for super-ordinates, contrary to results with object categories. In Experiment 3, subjects were fastest in recognizing actions as belonging to events named at the basic level. In Experiment 4, subjects predominantly chose basic-level terms to name stories. We conclude that event taxonomies do show basic-level structure, albeit a less sharply defined and less stable structure than in object taxonomies. The benefits and hazards of extending models of object concepts to other entities, such as social events, are discussed.  相似文献   
946.
A scale for assessing the complexity or density of utterances was developed using 10 categories ofsemantic relations (e.g., temporal ordering, causality). The categories are inferable from the particular meanings of the words (e.g., connectives, particular tense variations) used in an utterance. The scale was applied to three samples of subjects to assess its interjudge reliability and to compare the utterances of fourth-, sixth-, and eighth-grade children from middle- and working-class neighborhoods. It was also used to compare the complexity of utterances for different types of visual stimuli (used to elicit language samples). Interjudge reliabilities were more than acceptable for each of the samples, and significant differences in semantic density were found across grade, between children from working-class and middle-class neighborhoods, and for the stimuli used to elicit the utterances. When two of the three types of eliciting visual stimuli were equated for content and exposure conditions, the differences in verbal density between eliciting conditions were not replicated. The usefulness of the scale for assessing utterance density and by implication, comprehension difficulty of utterances and of texts, is discussed.This study was supported in part by a Grant from the National Institute of Education, U.S. Department of Health, Education and Welfare, Complexity in Auditory and Graphics Communication, Project No. 4-470. Points of view or opinions stated here do not necessarily represent National Institute of Education position or policy.  相似文献   
947.
948.
This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area.  相似文献   
949.
The purpose of this study was to examine the predictive validity of a teacher nomination procedure for identifying at- risk children. Two hundred and twenty-five children were nominated by their teachers as well- adjusted (n= 75), socially withdrawn (n=76), or socially aggressive (n=74) during the fourth grade. Five years later, 198 of these children (88%) were located and their adjustment evaluated. Significant differences among the nominated children were found on a variety of measures, including academic grades, sociometric status, and social behavior. In addition, differences in school dropout and delinquent offenses were noted. Results are discussed in terms of the validity of teacher nomination procedures and their utility in identifying at- risk youth.  相似文献   
950.
Twenty subjects were presented 240 randomized trials of a lexical decision task (LDT) while connected to a 16-electrode EEG montage. EEG data were acquired for 2 sec prior to the onset of each LDT trial. Alpha (9-13 Hz) coherence, alpha power, and 3- to 30-Hz power from five different combinations of EEG electrodes were used to predict semantic effects in the LDT trials. High pretrial coherence in the Right Hemisphere and Left Posterior-Parietal regions was associated with greater semantic facilitation (faster reaction times) in related-prime trials and greater semantic inhibition (slower reaction times) in unrelated-prime trials, relative to neutral-prime trials. No power variables were associated with semantic effects. Results support an information flow model of the functional significance of EEG coherence to cognitive processing.  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