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141.
James H. Wandersee 《科学教学研究杂志》1992,29(4):423-434
This article discusses the growing consensus across diverse educational research domains that the historical aspects of cognition are important for understanding not only how individuals but also disciplines know what they know. After proposing and defining the new superordinate concept of historicality, fundamental interrelationships between time, events, memory, meaning, personal knowledge, public knowledge, and the histories of the sciences are explored. Relevant research findings that demonstrate the confluence of scholarly thought concerning historicality across five educationally important domains are presented for the reader's consideration. Using the historicality concept, it is suggested that the histories of the sciences be considered as “the collective mind of scientists” and viewed as vital to developing students' knowledge about science by building upon the critical distinctions drawn by Duschl (1990). The author's science teaching technique, based upon construction of historical vignettes, is introduced here because of the relationship between history and story and the documented educational effectiveness of the story format. Finally, the author adds several cautionary notes about the validity of explanations based upon historicality and anticipates future advances in our understanding of the historicality of cognition. 相似文献
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On the validity and sensitivity of the phonics screening check: erratum and further analysis 下载免费PDF全文
Duff, Mengoni, Bailey and Snowling (Journal of Research in Reading, 38: 109–123; 2015) evaluated the sensitivity and specificity of the phonics screening check against two reference standards. This report aims to correct a minor data error in the original article and to present further analysis of the data. The methods used are calculation of predictive values of the phonics screening check in addition to sensitivity and specificity, and evaluation of agreement between the reference tests. Predictive values are important indicators of screening test quality. The positive predictive value of the phonics check is low (0.31) when compared with a standardised reading test but high (0.84) when compared with teachers' phonic phases judgements, reflecting poor agreement (kappa = 0.27) between reference tests. Results have implications for practice in terms of choice of reference standard and choice of threshold criterion for children to pass the screening check. Longitudinal data are needed to assess the predictive validity and utility of the check. What is already known about this topic:
- The importance of phonics in learning to read is widely acknowledged.
- The phonics screening check was introduced into U.K. schools in 2012 to ensure that all children develop phonic decoding skills.
- Estimates of the sensitivity and specificity of the phonics screening check, compared with two established ‘reference’ measures, were reported by Duff et al. ( 2015 ).
- We correct a minor error in the report of the original data by Duff et al. ( 2015 ).
- We draw attention to the importance of including predictive values, alongside sensitivity and specificity, in the evaluation of screening test validity. We also propose an alternative statistic for comparing the two reference measures.
- We show that applying this further analysis to the data in Duff et al. ( 2015 ) reveals the following: (i) the numbers of incorrect (false positive and false negative) outcomes in the phonics check and (ii) the marked difference in these numbers depending on the choice of reference measure.
- Reports of screening test validity should include positive and negative predictive values.
- A fundamental consideration for evaluating the validity of the phonics screening check is the choice of reference measure.
- Longitudinal data are needed to assess the predictive validity and utility of the phonics check.
144.
As low-stakes testing contexts increase, low test-taking effort may serve as a serious validity threat. One common solution to this problem is to identify noneffortful responses and treat them as missing during parameter estimation via the effort-moderated item response theory (EM-IRT) model. Although this model has been shown to outperform traditional IRT models (e.g., two-parameter logistic [2PL]) in parameter estimation under simulated conditions, prior research has failed to examine its performance under violations to the model’s assumptions. Therefore, the objective of this simulation study was to examine item and mean ability parameter recovery when violating the assumptions that noneffortful responding occurs randomly (Assumption 1) and is unrelated to the underlying ability of examinees (Assumption 2). Results demonstrated that, across conditions, the EM-IRT model provided robust item parameter estimates to violations of Assumption 1. However, bias values greater than 0.20 SDs were observed for the EM-IRT model when violating Assumption 2; nonetheless, these values were still lower than the 2PL model. In terms of mean ability estimates, model results indicated equal performance between the EM-IRT and 2PL models across conditions. Across both models, mean ability estimates were found to be biased by more than 0.25 SDs when violating Assumption 2. However, our accompanying empirical study suggested that this biasing occurred under extreme conditions that may not be present in some operational settings. Overall, these results suggest that the EM-IRT model provides superior item and equal mean ability parameter estimates in the presence of model violations under realistic conditions when compared with the 2PL model. 相似文献
145.
Current federal government policy initiatives in Aboriginal education and social welfare reform are based on assumptions about the relationship between increased attendance and increased student performance on standardized tests. There are empirical assumptions underlying these policy interventions and their accompanying public debates. Our aim here is to empirically explore the relationships between patterns of student attendance and patterns of student achievement in schools with significant cohorts of Aboriginal and/or Torres Strait Islander students at the school level. Based on an analysis of the publicly available data reported on the ‘MySchool’ website, we find that reforms and policies around attendance have not and are unlikely to generate patterns of improved achievement. Questions about the rationale and rhetoric of government policy focused at the school level as opposed to the need to focus on pedagogy and curriculum are discussed. 相似文献
146.
The purpose of this review was to synthesize the research on the relationship between performance on Piagetian tasks of concrete operations and performance on mathematics learning tasks in order to determine whether the Piagetian tasks make useful readiness measures. The research consistently indicates that, while there is a positive correlation between performance on Piagetian tasks and mathematics achievement, many school mathematics tasks can be mastered by children who have not yet developed the reasoning abilities measured by Piagetian tasks. This does not diminish the validity of Piaget's theory, but rather suggests that the kinds of reasoning processes identified by Piaget are not essential in solving many school mathematics tasks. 相似文献
147.
James L. Dolby 《Information processing & management》1977,13(1):69-77
One of the fundamental problems in information science is to distinguish various objects (such as books or journal articles) on the basis of associated values (such as authors and titles). Where the values fail to distinguish two distinct objects we say that the objects are ambigious under the given value assignment. To obtain a measure of ambiguity, it is only necessary to count the number of ways that the objects can be arranged for each set of ambiguous objects, multiply these counts and take logarithms. It is shown that such an approach leads to a measure in the formal sense and that the measure depends only on the definition of equality of values so that it can be simply extended to sets of values and ordered sets of values. It is also shown that it is possible to construct a function of ambiguity that one can call “information” and that the information loss that occurs when distinct values are grouped into equivalence classes (as in the use of search and sort keys) is also a measure. Finally, it is shown that ambiguity and information as here defined are directly related to Shannon's definition of “information” thus tieing this approach to that portion of information theory associated with the derivation of optimal distributions frequently used in information science models. 相似文献
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This study investigated eighth-grade science students’ (13–14-year-olds) perceptions of their vocabulary knowledge, learning, and content achievement. Data sources included pre- and posttest of students’ perceptions of vocabulary knowledge, students’ perceptions of vocabulary and reading strategies surveys, and a content achievement test. Students’ perceptions of vocabulary knowledge were compared before and after instruction to see whether students believed they gained knowledge and the ability to explain categories of technical science terms. Students’ perceptions of vocabulary knowledge increased as a result of instruction. The participants had favorable views of the vocabulary and reading strategies implemented and believed the literacy approaches were important for their developing science knowledge. In addition, students’ content achievement was compared to a national data set. Students in this study outperformed a national data set on all content knowledge items assessed. Students’ perceptions of their knowledge and vocabulary and reading strategies were congruent with their content achievement. This study is one of the first to highlight the pivotal role students’ perception of vocabulary knowledge and vocabulary and reading strategies plays in science content learning. 相似文献