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In this paper we add to the existing evidence base on recent trends in inter‐generational social mobility in England and Wales. We analyse data from the Office for National Statistics Longitudinal Study (ONS‐LS), which links individual records from the five decennial censuses between 1971 and 2011. The ONS‐LS is an excellent data resource for the study of social mobility because it has a very large sample size, excellent population coverage and low rates of nonresponse and attrition across waves. Additionally, the structure of the study means that we can observe the occupations of LS‐members' parents when they were children and follow their own progress in the labour market at regular intervals into middle age. Counter to widespread prevailing beliefs, our results show evidence of a small but significant increase in social fluidity between 1950s and the 1980s for both men and women.  相似文献   
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Increasing demands for accountability in educational programming have resulted in increasing calls for program evaluation in educational organizations. Many organizations include conducting program evaluations as part of the job responsibilities of program staff. Cooperative Extension is a complex organization offering non-formal educational programs through land grant universities. Many Extension services require non-formal educational program evaluations be conducted by field-based Extension educators. Evaluation research has focused primarily on the efforts of professional, external evaluators. The work of program staff with many responsibilities including program evaluation has received little attention. This study examined how field based Extension educators (i.e. program staff) in four Extension services use the results of evaluations of programs that they have conducted themselves. Four types of evaluation use are measured and explored; instrumental use, conceptual use, persuasive use and process use.Results indicate that there are few programmatic changes as a result of evaluation findings among the non-formal educators surveyed in this study. Extension educators tend to use evaluation results to persuade others about the value of their programs and learn from the evaluation process. Evaluation use is driven by accountability measures with very little program improvement use as measured in this study.Practical implications include delineating accountability and program improvement tasks within complex organizations in order to align evaluation efforts and to improve the results of both. There is some evidence that evaluation capacity building efforts may be increasing instrumental use by educators evaluating their own programs.  相似文献   
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Adaptive trial methodology for multiarmed trials and enrichment designs has been extensively discussed in the past. A general principle to construct test procedures that control the family‐wise Type I error rate in the strong sense is based on combination tests within a closed test. Using survival data, a problem arises when using information of patients for adaptive decision making, which are under risk at interim. With the currently available testing procedures, either no testing of hypotheses in interim analyses is possible or there are restrictions on the interim data that can be used in the adaptation decisions as, essentially, only the interim test statistics of the primary endpoint may be used. We propose a general adaptive testing procedure, covering multiarmed and enrichment designs, which does not have these restrictions. An important application are clinical trials, where short‐term surrogate endpoints are used as basis for trial adaptations, and we illustrate how such trials can be designed. We propose statistical models to assess the impact of effect sizes, the correlation structure between the short‐term and the primary endpoint, the sample size, the timing of interim analyses, and the selection rule on the operating characteristics.  相似文献   
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General Representation of Epistemically Optimal Procedures   总被引:1,自引:1,他引:0  
Assuming that votes are independent, the epistemically optimal procedure in a binary collective choice problem is known to be a weighted supermajority rule with weights given by personal log likelihood ratios. It is shown here that an analogous result holds in a much more general model. Firstly, the result follows from a more basic principle than expected-utility maximisation, namely from an axiom (“Epistemic Monotonicity”) which requires neither utilities nor prior probabilities of the ‘correctness’ of alternatives. Secondly, a person’s input need not be a vote for an alternative; it may be any type of input, for instance a subjective degree of belief or probability of the correctness of one of the alternatives. The case of a profile of subjective degrees of belief is particularly appealing, since no parameters such as competence parameters need to be known here.  相似文献   
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The aim of this paper is to study the concept of separability in multiple nonstationary time series displaying both common stochastic trends and common stochastic cycles. When modeling the dynamics of multiple time series for a panel of several entities such as countries, sectors, firms, imposing some form of separability and commonalities is often required to restrict the dimension of the parameter space. For this purpose we introduce the concept of common feature separation and investigate the relationships between separation in cointegration and separation in serial correlation common features. Loosely speaking we investigate whether a set of time series can be partitioned into subsets such that there are serial correlation common features within the sub-groups only. The paper investigates three issues. First, it provides conditions for separating joint cointegrating vectors into marginal cointegrating vectors as well as separating joint short-term dynamics into marginal short-term dynamics. Second, conditions for making permanent-transitory decompositions based on marginal systems are given. Third, issues of weak exogeneity are considered. Likelihood ratio type tests for the different hypotheses under study are proposed. An empirical analysis of the link between economic fluctuations in the United States and Canada shows the practical relevance of the approach proposed in this paper.  相似文献   
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