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   5448篇
  免费   104篇
管理学   757篇
民族学   15篇
人才学   6篇
人口学   524篇
丛书文集   16篇
理论方法论   469篇
综合类   63篇
社会学   2490篇
统计学   1212篇
  2021年   36篇
  2020年   72篇
  2019年   105篇
  2018年   114篇
  2017年   178篇
  2016年   111篇
  2015年   79篇
  2014年   101篇
  2013年   919篇
  2012年   197篇
  2011年   142篇
  2010年   107篇
  2009年   104篇
  2008年   115篇
  2007年   131篇
  2006年   119篇
  2005年   120篇
  2004年   118篇
  2003年   85篇
  2002年   114篇
  2001年   134篇
  2000年   104篇
  1999年   123篇
  1998年   101篇
  1997年   104篇
  1996年   75篇
  1995年   79篇
  1994年   93篇
  1993年   79篇
  1992年   90篇
  1991年   77篇
  1990年   85篇
  1989年   79篇
  1988年   92篇
  1987年   84篇
  1986年   76篇
  1985年   84篇
  1984年   69篇
  1983年   72篇
  1982年   65篇
  1981年   62篇
  1980年   55篇
  1979年   74篇
  1978年   60篇
  1977年   49篇
  1976年   59篇
  1975年   57篇
  1974年   34篇
  1973年   38篇
  1971年   30篇
排序方式: 共有5552条查询结果,搜索用时 218 毫秒
301.
The extent of men’s roles in reproductive decision-making in Africa is a subject of contention. Despite the volume of work on the roles men play in fertility decisions, there have been few attempts to derive direct empirical estimates of the effect of men’s preferences on reproductive behavior. I employ 1989 and 1993 Kenya Demographic and Health Surveys to examine the relative roles of the reproductive preferences of males and females on contraceptive use. Additive and interactive measures of preferences document a significant effect of men’s preferences, which may eclipse women’s preferences. The implications of these findings are discussed.  相似文献   
302.
ABSTRACT: In reaction to growing criticism of the allegedly negative employment effects of job protection regulations (lay-off and dismissal restraints), the West German government in 1985 introduced new legislation facilitating the conclusion of temporary (i.e. fixed-term) work contracts in order to stimulate employment growth (‘Employment Promotion Act 1985‘AZPA). The research unit ‘Labour Market and Employment‘ at the WZB has evaluated the employment and labour market impact of the new legislation for the period 1985-1988, and apart from providing a detailed analysis of the socio-economic and institutional diversity of job arrangements covered by the category of temporary (i.e. fixed-term) employment, the project‘s focus has been on the impact of minor changes in the institutional frame- work as effected by the EPA on firms‘ employment policies, as well as on the overall level of employment. Results show that like in most other European countries the temporary work force in Germany has considerably grown over the past years in both absolute and relative terms, this increase, however, being largely due to cyclical factors as well as medium-term structural changes on the supply and demand side of the labour market rather than to changes in the regulatory framework as effected by the EPA. The impact of the new regulations on firms‘ hiring decisions and on the overall number of hirings in the total economy have to be regarded as rather modest, in fact amounting to not more than an estimated 25,000 additional hires per year or roughly 0.5|X% of all employment contracts concluded in the private sector. This marginal positive impact on firms‘ employment decisions, however, is counterbalanced by unintended substitution effects and an increase in involuntary quits arising from them when labour demand declines. Even under the overall positive employment development given in the period under investigation the net employment effects of the EPA temporary work legislation thus are shown to be at best marginal. In case of a deterioration of the overall economic situation, however, the increase in temporary job arrangements supported by the new legislation is likely to lead to accelerated workforce adjustments by firms and thus over time to result in a depression of the overall level of employment. From a theoretical point of view, the findings suggest that measures aiming at de-regulating labour relations such as the EPA largely fail to modify essential behavioral parameters of economic actors in economic environments which for decades have adjusted to a relatively high level of welfare state regulation, as has been the case in Western Germany.  相似文献   
303.
User information satisfaction (UIS) is important because of its potential effects on MIS department goals, quality of user work life, and extent of voluntary usage of systems. Reliable measurement of UIS is important for providing evaluative information for both researchers and practitioners. This study used 92 managers and executives as subjects to compare the test/retest reliability of a widely used, 13-scale UIS instrument together with four summary questions under experimental and control conditions. The summary questions behaved more reliably than the detailed questions for all groups, perhaps because of problems with scale units and origins and with item heterogeneity. This suggests that researchers need more reliable measures of UIS and that practitioners need to exercise caution when collecting and interpreting UIS scores.  相似文献   
304.
Based on Dutch colonial registers (thombos), this paper reconstructs fertility for two districts in Ceylon, 1756–68. It overcomes challenges in data quality by establishing the outer bounds of plausible estimates in a series of scenarios. Among these, total fertility rates (TFRs) averaged 5.5 in one district, but only 2.7 in the other. These figures exclude the victims of infanticide, a custom noted in European travelogues between about 1660 and 1820. Sex ratios among children differed depending on the number of older siblings, and overall, 27?per cent of girls are missing in one district and 57?per cent in the other. There was little significant variation either in the TFR or the sex ratio by socio-economic status, suggesting that poverty was not a key factor in motivating infanticides. Instead, we argue that at least parts of Ceylon had a forward-looking culture of family planning in the eighteenth century, which was lost in subsequent decades.  相似文献   
305.
Much of the sociological and historical literature, ignoring long-standing interclass disputes over integration, takes for granted that during the 1950s, all blacks, parents, and members of civil rights organizations included, sought desegregation. This article examines the interests of different segments of New York City's black community regarding the public schools during that era. I use contemporary newspaper accounts of protests and more recent theoretical insights to analyze and interpret differences in expressed goals and demands. This article not only documents considerable educationally oriented protest in a Northern city during a decade often overlooked by scholars, but highlights important class-based differences within a single city's black community regarding changes needed. Of particular interest to social movement scholars are findings that reveal a large disjuncture between the demands of the grassroots parents' organizations and established, elite civil rights organizations. While civil rights organizations sought abstract ideals of integration, parents demanded tangible improvements in their children's schools. Class-based cultures and experiences are posited as the root of this disjuncture.  相似文献   
306.
This study proposes a usefulalternative to the ``aggregate deprivationindex' which is used to measure the well-beingsof individuals in different countries orgeographic locations. Furthermore, we alsopropose an improvement index which alleviateswell known difficulties associated withovertime comparisons of ``aggregate deprivationindex'. While deriving our indexes, we pursuedan economic approach to index numbers theoryand relied on the assumptions of optimizingbehavior. The proposed achievement index hasits roots in the theory of quantity indexeswhose axiomatic properties are wellestablished. The roots of our improvement indexon the other hand, is well grounded in theproductivity growth literature. The study alsoprovides a numerical example.  相似文献   
307.
This paper reports the results of a prospective experiment in which a group of approximately 4,000 participants in the Transcendental Meditation and TM-Sidhi programs of Maharishi Mahesh Yogi assembled in Washington, D.C., from June 7 to July 30, 1993. It was hypothesized that levels of violent crime in the District of Columbia would fall substantially during the Demonstration Project, as a result of the group's effect of increasing coherence and reducing stress in the collective consciousness of the District. A 27-member Project Review Board comprising independent scientists and leading citizens approved the research protocol and monitored the research process. Weekly crime data was derived from database records provided by the District of Columbia Metropolitan Police Department (DCMPD), which are used in the FBI Uniform Crime Reports. Statistical analysis considered the effect of weather variables, daylight, historical crime trends and annual patterns in the District of Columbia, as well as trends in neighboring cities. Consistent with previous research, levels of homicides, rapes and assaults (HRA crimes) correlated with average weekly temperature. Robberies approximately followed an annually recurring cycle. Time series analysis of 1993 data, controlling for temperature, showed that HRA crimes dropped significantly during the Demonstration Project, corresponding with increases in the size of the group; the maximum decrease was 23.3% (p < 2 × 10–9) [24.6% using a longer baseline, with 1988--1993 data (p < 3 × 10–5)], coincident with the peak number of participants in the group during the final week of the assembly. When the same period in each of the five previous years was examined, no significant decreases in HRA crimes were found. Robberies did not decrease significantly. However, a model that jointly estimated the effect of the Demonstration Project on both HRA crimes and robberies showed a significant reduction in violent crimes overall of 15.6% (p = 0.0008). Further analysis showed that the effect of the coherence-creating group on reducing HRA crimes could not be accounted for by additional police staffing. The time series analysis for HRA crimes gave results that are highly robust to alternative model specifications, and showed that the effect of the group size was cumulative and persisted after the Demonstration Project ended. Also, calculation of the steady state gain based on the time series model predicted that a permanent group of 4,000 coherence-creating experts in the District would have a long-term effect of reducing HRA crimes by 48%.  相似文献   
308.
309.
Summary An equation is given for the estimation of selective values from data obtained by mark-recapture experiments, assuming that selective pressures remain constant while the experiments are carried out. The equation does not have an explicit solution but can readily be solved using a trial-and-error method. The use of the equation is illustrated on some data reported byKettlewell et al. (1969) from an experiment involvingtypica andedda morphs of the mothAmathes glareosa. It is found that theedda morph apparently had a selective advantage of about 12% per day compared to thetypica morph and that this is significantly different from zero. Using another methodKettlewell concluded that the selective advantage of theedda morph was only 7% and that this was not statistically significant.  相似文献   
310.
This study investigates the effects of time and probability constraints on the search process in a decision-making situation. The setting was a behavioral laboratory in which subjects were asked to choose one art print from a selection of 260 prints. The prints were in sets of five for convenience in showing. In the nonconstraint condition, subjects were able to set their own pace in viewing prints and could obtain any print in the whole set that was desired. Under the constraint condition, the time and probability constraints were both operative. Under the time constraint, viewing additional sets required increasing amounts of time. Under the probability constraint, there was a constantly reducing probability—down to a minimum of ten percent—of obtaining an earlier print as more prints were viewed. In comparison to unconstrained subjects, constrained subjects viewed fewer prints and did more rechecking in total while the search was in process.  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