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   28733篇
  免费   609篇
  国内免费   18篇
管理学   3980篇
民族学   217篇
人才学   10篇
人口学   3868篇
丛书文集   184篇
理论方法论   2397篇
综合类   1017篇
社会学   14070篇
统计学   3617篇
  2023年   106篇
  2022年   83篇
  2021年   147篇
  2020年   301篇
  2019年   404篇
  2018年   2089篇
  2017年   2241篇
  2016年   1523篇
  2015年   423篇
  2014年   491篇
  2013年   3000篇
  2012年   990篇
  2011年   1774篇
  2010年   1546篇
  2009年   1212篇
  2008年   1360篇
  2007年   1565篇
  2006年   600篇
  2005年   777篇
  2004年   703篇
  2003年   618篇
  2002年   505篇
  2001年   448篇
  2000年   434篇
  1999年   391篇
  1998年   301篇
  1997年   264篇
  1996年   272篇
  1995年   248篇
  1994年   257篇
  1993年   245篇
  1992年   272篇
  1991年   244篇
  1990年   230篇
  1989年   211篇
  1988年   241篇
  1987年   235篇
  1986年   192篇
  1985年   210篇
  1984年   236篇
  1983年   199篇
  1982年   204篇
  1981年   168篇
  1980年   158篇
  1979年   160篇
  1978年   123篇
  1977年   109篇
  1976年   130篇
  1975年   131篇
  1974年   115篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
71.
The Coase theorem maintains that where free-market precepts exist, the allocation of property rights does not impact the distribution of resources. An application to Major League Baseball suggests that institutions such as free agency and the reverse-order amateur draft would not impact player distributions and therefore would not impact competitive balance. The present study finds that the distribution of wins is generally consistent with the precepts of the Coase theorem and therefore suggests a course for those who wish to alter the level of competitive balance: Major League Baseball should increase its focus on expanding the size of its labor pool. (JEL O15 , L83 , C22 )  相似文献   
72.
73.
Many recent institutional reforms of the financial system have relied on the introduction of an explicit scheme of deposit insurance. This instrument aims at two main targets, contributing to systemic stability and protecting depositors. However, it may also affect the interest rate spread in the banking system, which can be viewed as an indicator of either inefficiency or market power in this financial segment. This paper provides an empirical investigation of the effect of deposit insurance and other institutional and economic variables on bank interest rates across countries. We find that deposit insurance increases the lending–deposit spread in banking. The main effect seems to arise not from the deposit side though, but from an increase in the lending rate. We interpret this result as evidence of the presence of moral hazard problems related to this instrument. We also find that higher quality of institutions is associated with lower spreads, thus contributing to eroding sources of market power in the banking sector.  相似文献   
74.
For testing the fit of the inverse Gaussian distribution with unknown parameters, the empirical distribution-function statistic A2 is studied. Two procedures are followed in constructing the test statistic; they yield the same asymptotic distribution. In the first procedure the parameters in the distribution function are directly estimated, and in the second the distribution function is estimated by its Rao-Blackwell distribution estimator. A table is given for the asymptotic critical points of A2. These are shown to depend only on the ratio of the unknown parameters. An analysis is provided of the effect of estimating the ratio to enter the table for A2. This analysis enables the proposal of the complete operating procedure, which is sustained by a Monte Carlo study.  相似文献   
75.
76.
VII. Conclusion The number of immigrants now coming to the United States is proportionally only a fraction of the number that came in earlier years, and there is nothing in those numbers to suggest a difficult absorption burden. Immigrants, both legal and illegal, more than pay for the services they use with the taxes they pay, leaving a considerable net surplus that benefits American citizens. Immigrants raise productivity and do not cause an observable amount of unemployment of citizens. Admitting far more immigrants into the country than the law now allows would have positive effects on the incomes of citizens, and would enhance the continuing vitality of the United States.  相似文献   
77.
In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse.  相似文献   
78.
Summary Meta-analyses of sets of clinical trials often combine risk differences from several 2×2 tables according to a random-effects model. The DerSimonian-Laird random-effects procedure, widely used for estimating the populaton mean risk difference, weights the risk difference from each primary study inversely proportional to an estimate of its variance (the sum of the between-study variance and the conditional within-study variance). Because those weights are not independent of the risk differences, however, the procedure sometimes exhibits bias and unnatural behavior. The present paper proposes a modified weighting scheme that uses the unconditional within-study variance to avoid this source of bias. The modified procedure has variance closer to that available from weighting by ideal weights when such weights are known. We studied the modified procedure in extensive simulation experiments using situations whose parameters resemble those of actual studies in medical research. For comparison we also included two unbiased procedures, the unweighted mean and a sample-size-weighted mean; their relative variability depends on the extent of heterogeneity among the primary studies. An example illustrates the application of the procedures to actual data and the differences among the results. This research was supported by Grant HS 05936 from the Agency for Health Care Policy and Research to Harvard University.  相似文献   
79.
80.
The theory of family paradigms provides an integrative framework for under-standing and systematizing the diverse ways that families organize and make sense of family life. Using formal methods of analysis based on logical and geometrical arguments, the priecise implications of models of family types can be investigated and compared. The paradigmatic framework can thus be refined and extended to form a more rigorous theoretical grounding for family typologies is explored and a miltidimensional model is derived the geometry of which is equivalent to, but more succinctly captures, the underlying structure of uariation in family para-digms. In Part II, the resulting model is interpredtd and explored in terms of implications for family theory, theory construction, and family therapy. Clarifying the basic dimensions of the paradigmatic framework also permits more precise exploration of interrelationships among related models of family types, which can be understood as reduced models derivable from the complete geometry of the paradigmatic framework.  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