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   11594篇
  免费   195篇
  国内免费   2篇
管理学   1603篇
民族学   43篇
人才学   1篇
人口学   988篇
丛书文集   57篇
理论方法论   1061篇
综合类   155篇
社会学   5502篇
统计学   2381篇
  2023年   69篇
  2020年   159篇
  2019年   240篇
  2018年   248篇
  2017年   351篇
  2016年   263篇
  2015年   214篇
  2014年   254篇
  2013年   2075篇
  2012年   345篇
  2011年   302篇
  2010年   272篇
  2009年   261篇
  2008年   325篇
  2007年   333篇
  2006年   297篇
  2005年   268篇
  2004年   246篇
  2003年   236篇
  2002年   266篇
  2001年   250篇
  2000年   229篇
  1999年   216篇
  1998年   191篇
  1997年   197篇
  1996年   200篇
  1995年   152篇
  1994年   131篇
  1993年   166篇
  1992年   180篇
  1991年   170篇
  1990年   174篇
  1989年   142篇
  1988年   134篇
  1987年   149篇
  1986年   119篇
  1985年   110篇
  1984年   159篇
  1983年   143篇
  1982年   131篇
  1981年   109篇
  1980年   124篇
  1979年   128篇
  1978年   96篇
  1977年   112篇
  1976年   96篇
  1975年   102篇
  1974年   79篇
  1973年   77篇
  1972年   66篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
161.
162.
Summary Ledermann's one- and two-parameter model life tables are used in order to summarize and compare adult mortality estimates derived from parental survival data, and also to link parental survival with child survival data. The Ledermann models provide an alternative to the logit model used by Brass and Hill. Examination of life tables derived from actual child and adult mortality estimates reveals that although the two types of models yield similar overall levels of mortality, they show marked differences in the estimated patterns by sex and age. It has not been possible to disentangle completely how much of this divergence is due to the models themselves and how much to inadequacies in the data available. Finally, we question whether it is always wise to establish a full life table from child and adult mortality estimates when these are based on data which refer to different periods of exposure to the risk of dying, without allowance for possible distortions resulting from mortality change.  相似文献   
163.
In two experiments, refusal rates to telephone interviews werenot affected by substantial changes in the introductory remarksof the interviewer. A prior letter significantly lowered refusalrates in a third experiment. In all three, interviewer sex hadno effect.  相似文献   
164.
Summary It is generally conceded that our allied mental health professions have fallen short in our attempts to provide adequate services to those people whose need is most desperate, those individuals and families ambiguously and condescendingly designated multiproblem. It could be said that we, the caregivers, have been unwilling or unable to be good enough mothers to these, our motherless children. In fact, the early, formative experience of the people with whom we are concerned has invariably been marked by gross discontinuities in mothering; the consequent defects in controlling, regulatory psychic structure (ego defects) are most prominently manifested in the chaotic life-style which characterizes these individuals and families. Our task as caregivers, when viewed from this perspective, is clear: we must somehow bring order out of disorder. But, with tragic regularity, disorder prevails; the provider of service succumbs to the same painful feelings of disorganization, bewilderment, frustration, and helplessness with which his client struggles, and, eventually, both give up in despair. What is more, this sense of fragmentation and futility pervades the institutions responsible for provision of services. Client, caregiver, and institution, all are trapped in the same tortuous maze. How, then, are we to extricate ourselves? Certainly not by drafting yet another master plan which promises everything and delivers nothing. Both realistic and humanistic considerations dictate more modest goals: We might not be able to rescue everyone who needs assistance, but we can help a few. And, whatever approach we may adopt, the service we offer can only be effective if it is based upon a sustained and sustaining (in essence, maternal) relationship.Sometimes I Feel Like a Motherless Child  相似文献   
165.
166.
We use an event-study analysis to understand how alliance activity affects firm risk. The risk measure is the implied volatility of a firm’s stock price and the events are alliance announcements to the market. We build on the previous event-studies in the alliance literature that focus on the change in shareholder value by taking the first step in delineating what part of that value arises from the changes in the firm’s risk. The analysis reveals that a number of factors within a firm’s control can be used to manipulate risk exposure in an alliance, including the similarity of the firm’s and the alliance’s core activities, the governance form of the alliance, and the function of the alliance.  相似文献   
167.
The purpose of this paper is to present the theory of the multi-product firm in situations where the revenue function depends not only on the rate of output but also on changes in the rate of output, and, similarly, where the cost function depends on changes in the rate of factor utilization as well as the rate of their utilization. Since the analysis will utilize the calculus of variations, a general introduction to this technique is also presented. The model analyzed assumes perfect foresight and knowledge concerning the revenue, cost, and production functions, and the calculus of variations is used to derive the conditions for an extremum. The first section presents the mathematical model and the model of the firm, and the optimality conditions are discussed in the second section.  相似文献   
168.
169.
170.
In this paper we investigate the asymptotic critical value behaviour of certain multiple decision procedures as e.g. simultaneous confidence intervals and simultaneous as well as stepwise multiple test procedures. Supposing that n hypotheses or parameters of interest are under consideration we investigate the critical value behaviour when n increases. More specifically, we answer e.g. the question by which amount the lengths of confidence intervals increase when an additional parameter is added to the statistical analysis. Furthermore, critical values of different multiple decision procedures as for instance step-down and step-up procedures will be compared. Some general theoretic results are derived and applied for various distributions.  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