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   415篇
  免费   4篇
管理学   61篇
民族学   1篇
人口学   34篇
丛书文集   1篇
理论方法论   18篇
社会学   62篇
统计学   242篇
  2023年   3篇
  2021年   3篇
  2020年   7篇
  2019年   9篇
  2018年   12篇
  2017年   20篇
  2016年   14篇
  2015年   10篇
  2014年   13篇
  2013年   135篇
  2012年   7篇
  2011年   8篇
  2010年   8篇
  2009年   15篇
  2008年   8篇
  2007年   23篇
  2006年   11篇
  2005年   2篇
  2004年   4篇
  2003年   2篇
  2002年   6篇
  2001年   5篇
  2000年   4篇
  1999年   6篇
  1998年   6篇
  1997年   7篇
  1996年   6篇
  1995年   3篇
  1994年   3篇
  1993年   2篇
  1992年   2篇
  1990年   4篇
  1989年   3篇
  1988年   3篇
  1987年   2篇
  1985年   7篇
  1984年   4篇
  1983年   2篇
  1982年   2篇
  1981年   4篇
  1980年   3篇
  1979年   3篇
  1977年   3篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
  1973年   3篇
  1972年   3篇
  1971年   1篇
  1970年   1篇
排序方式: 共有419条查询结果,搜索用时 781 毫秒
101.
In this paper we study the minimum variance unbiased estimation in the modified power series distribution introduced by the author (1974a). Necessary and sufficient conditions for the existence of minimum variance unbiased estimate (MVUE) of the parameter based on sufficient statistics are obtained. These results are, then, applied to obtain MVUE of θr (r ≥ 1) for the generalized negative binomial and the decapitated generalized negative binomial distributions (Jain and Consul, 1971). Similar estimates are obtained for the generalized Poisson (Consul and Jain, 1973a) and the generalized logarithmic series distributions (Jain and Gupta, 1973). Several of the well-known results follow trivially from the results obtained here.  相似文献   
102.
In this paper, we give a lower bound for the number of treatments required

for a plan to be a main effect plus one plan for 2m (m = 6) factorial experiments, The lower bound problem is important in the event of generating new designs with similar properties or when one wants to study the criteria of optimality for such designs.  相似文献   
103.
In this paper the moments of the likelihood ratio statistic for testing the structure of mean vector of a compound symmetric Gaussian model, have been derived by using the orthogonal transformation of variables. Then the distribution of the test statistic is studied.  相似文献   
104.
In this paper we have considered the problem of finding admissible estimates for a fairly general class of parametric functions in the so called “non-regular” type of densities Following Karlin s (1958) technique, we have established the ad-missibility of generalized Bayes estimates and Pitman estimates. Some examples are discussed.  相似文献   
105.
Modelling age-specific fertility rates is of great importance in demography because of their influence on population growth. Although we have a variety of fertility models in the demographic literature, most of them do not have any demographic interpretation for their parameters. It is generally expected that models with behavioural interpretation are more universal than those without any interpretation. Even though the famous Gompertz model has some behavioural interpretation it suffers from other drawbacks. In the present work, we propose a new fertility model, which has its genesis in the generalization of logistic law. The proposed model has good behavioural interpretation, alongside having nice parameter interpretations.  相似文献   
106.
In this study we investigated whether the following factors influenced married partners' reactions to spousal support: type of support (directive vs. nondirective); individual differences (gender, depressive symptoms); and dimension along which support was evaluated (level of helpfulness vs. valence of emotional impact). Nondirective support was consistently rated more favorably on the dimension of partner's impact than on the dimension of partner's helpfulness, and this effect was exaggerated for those self-reporting a high level of depressive symptoms. Nonetheless, directive support was provided more frequently than was nondirective support in this sample. Gender differences and complications introduced by partner dysphoria suggest some situations in which directive support may be particularly difficult to provide effectively. Implications for couple therapy are discussed.  相似文献   
107.
In this paper, the testing and estimation of a single change point in means and variances of a sequence of independent Gaussian normal random variables are studied. The Schwarz Information Criterion, SIC, is used to search for the change point. The unbiased version of the SIC for this change point problem is also derived for the finite sample case. Other properties of the SIC test statistic are given as well. Finally, two examples are given at the end of this paper to illustrate the method proposed, and changes are successfully detected.  相似文献   
108.
A model of advertising effects has been developed based on a distinction between “persuasion” advertising and “trigger” advertising. The former is designed to induce prospective purchasers to try the product and to establish a “product image”. The latter is aimed at “triggering” a purchase on the part of an individual whose image of the product has already been formed. The distinction has major implications for the type and timing of advertising. The model can be applied to determining an optimum distribution of advertising effort in the introduction of a new product, and the optimum advertising media mix.  相似文献   
109.
Recent studies have shown the high prevalence of youth gambling behavior. In particular, lottery ticket purchases among children and adolescents appear to be a highly preferred activity. Despite this fact, most research has focused on the underlying erroneous cognitions used by adults when selecting lottery tickets. This study examines the cognitive perceptions of children while engaged in selecting 6/49 lottery tickets. One hundred sixty-seven children (61 females; 106 males) from grades 3, 5, and 7 were asked to rank pre-selected 6/49 lottery tickets which were classified into a) long series, b) specific patterns, c) non equilibrated numbers, or d) perceived random selections. Children verbalized their rationale for selecting each ticket and were permitted to change the numbers on the lottery tickets they liked least in order to make them to more likely to be the winning ticket. Findings, in general, revealed small developmental differences in the types of underlying cognitive heuristics used by the children. The use of cognitive heuristics underlying the concept of randomness and the use of significant and meaningful numbers was observed to increase as children got older. Children between 9 and 11 were found to have employed the cluster heuristic more frequently than older children, ages 12–13. The results are interpreted in terms of the cognitive developmental changes in children's perceptions and the potential implication for gambling prevention programs are provided.  相似文献   
110.
V.K. Gupta  J.G. Chen  M.B. Murtaza 《Omega》1997,25(6):715-727
In several key functional areas of contemporary engineering and management science, neural networks have steadily been gaining recognition as robust and reliable tools for classification problems. This paper describes a new application of the learning vector quantization neural network: the classification of the degree of modularization appropriate for the construction of an industrial facility. This neural network uses variables related to plant location, labor issues, organizational issues, plant characteristics, project risks, and environmental issues as inputs to perform the classification. The neural network training and performance evaluation is also discussed.  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