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   97536篇
  免费   2999篇
  国内免费   6篇
管理学   13255篇
民族学   576篇
人才学   25篇
人口学   8019篇
丛书文集   540篇
教育普及   1篇
理论方法论   9877篇
综合类   2250篇
社会学   46686篇
统计学   19312篇
  2023年   521篇
  2021年   596篇
  2020年   1547篇
  2019年   2244篇
  2018年   2289篇
  2017年   3360篇
  2016年   2565篇
  2015年   2078篇
  2014年   2682篇
  2013年   19035篇
  2012年   2765篇
  2011年   2603篇
  2010年   2185篇
  2009年   2283篇
  2008年   2300篇
  2007年   2133篇
  2006年   2285篇
  2005年   2457篇
  2004年   2333篇
  2003年   2035篇
  2002年   2147篇
  2001年   2287篇
  2000年   2040篇
  1999年   1886篇
  1998年   1623篇
  1997年   1479篇
  1996年   1443篇
  1995年   1454篇
  1994年   1410篇
  1993年   1380篇
  1992年   1441篇
  1991年   1395篇
  1990年   1365篇
  1989年   1201篇
  1988年   1268篇
  1987年   1131篇
  1986年   1053篇
  1985年   1214篇
  1984年   1255篇
  1983年   1126篇
  1982年   1027篇
  1981年   918篇
  1980年   879篇
  1979年   964篇
  1978年   848篇
  1977年   756篇
  1976年   699篇
  1975年   677篇
  1974年   575篇
  1973年   481篇
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
501.
In this note we prove some inequalities for variances and other measures of deviation of functions of random variables. Based on these inequalities we find some corollaries concerning the variances of fractional powers of random variables and of sums of independent random variables.  相似文献   
502.
In a recent paper in this journal, Lee, Kapadia and Brock (1980) developed maximum likelihood (ML) methods for estimating the scale parameter of the Rayleigh distribution from doubly censored samples. They reported convergence difficulties in attempting to solve numerically the nonlinear likelihood equation (LE). To mitigate these difficulties, they employed approximations to simplify the LE, but found that the solution of the resulting simplified equation can give rise to parameter estimates of erratic accuracy. We show that the use of approximations to simplify the LE is unnecessary. In fact, under suitable parametric transformation, the log-likelihood function is strictly concave, the ML estimate always exists, is unique and finite. Furthermore, the LE is easy to solve numerically. A numerical example is given to illustrate the computations involved.  相似文献   
503.
Victims of spouse abuse were interviewed concerning their views of why their husbands were abusive. It was hypothesized that by concentrating on one specific characteristic of this kind previously undocumented patterns of response would be elicited from the subjects. It was concluded that the women's reasons for the violence perpetrated by their spouses serve as justification for the abusers’actions and legitimize maintenance of the relationship.  相似文献   
504.
Dental caries in children is now recognized as a preventable disease. The use of fluoride and sealants has produced a major reduction in caries prevalence among school aged children in the United States and other countries. A portion of the child population who are educationally and socioeconomically disadvantaged are not fully receiving these benefits. Public policy, insurance and medicaid groups must be made aware of these preventative measures and strategies developed to implement them.  相似文献   
505.
Using mail survey data based on a stratified systematic sample [N = 686] of 1983–1988 graduates of a medium-sized state university, this research evaluates whether ROTC program participation constitutes an independent source of human capital in civilian labor markets by comparing postgraduate earnings (annual income), prestige and authority, and life satisfaction of ROTC program participants with those of nonparticipants. The results revealed no statistically significant ROTC program participation effects, independent of subsequent military status. ROTC program participation paid off in terms of occupational prestige and authority for those on active duty, but not for those in national guard or reserve units. Neither ROTC participation nor current military status affected income or life satisfaction levels.  相似文献   
506.
Although research has examined the corruptive influences of undercover drug operations on agents (Girodo 1991 b; Manning and Reddlinger 1977, 1978), it has not examined the processes by which these influences can be neutralized. In this paper, I address these neutralization processes through a typology of routine and non-routine drug-use evasion tactics. Routine tactics involve excuses based on greed, business constraints, and role obligations (occupational, legal, and interpersonal). Nonroutine tactics involve two components: reverse accusation and simulation. Discussion focuses on excuses where I provide a dramaturgical interpretation that accentuates their deceptive and fraudulent nature, unlike traditional interpretations (e.g., Scott and Lyman 1968) which highlight their role as a reparative technique and aligning action (Margolin 1990). Data were drawn from ethnographic interviews with 35 light undercover narcotics agents located in a moderate-sized midwestern municipality.  相似文献   
507.
This paper develops a Coase-like solution of the problem of inducing Pareto optimal behavior in the presence of reciprocal externalities. In place of Coasean direct compensation between the parties to an externality problem, actors strategically match each other's externality-producing activity, and thus induce counterparts to internalize the external benefits or costs of their actions. The analysis suggests a general framework for analyzing social interactions in the presence of reciprocal externalities. As an application of the theory, a solution of the duopoly problem is noted.We are indebted to L. Danziger, D. Samet, participants in faculty seminars at Bar-Ilan and New York Universities and at the University of Maryland, and two anonymous referees for helpful comments and discussions. All remaining errors are our own.  相似文献   
508.
In this paper we argue for the importance of a sociologically informed study of organizational accounting practices. By making the nexus between accounting and decision making problematic, instead of given, we move issues of interpretation and hierarchical control to the center stage of understanding the social construction of accounting practices. We suggest that inductive case studies of the organizational setting is a promising methodological strategy for identifying how accounting operates as an organizational control system. We focus on debates and proceedings of the board of directors as an overlooked source of data on decision making and organizational practices. We show how accounting practices are part of the strategic control system that functions to interpret the environment and direct the adaptation of the organization in a manner particular to the substantive rationality of corporate decision makers. We illustrate these contentions with a case study of accounting practice changes over a six year period.  相似文献   
509.
510.
We propose a new modified (biased) cross-validation method for adaptively determining the bandwidth in a nonparametric density estimation setup. It is shown that the method provides consistent minimizers. Some simulation results are reported on which compare the small sample behavior of the new and the classical cross-validation selectors.  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