全文获取类型
收费全文 | 29656篇 |
免费 | 612篇 |
国内免费 | 1篇 |
专业分类
管理学 | 4097篇 |
民族学 | 197篇 |
人口学 | 3978篇 |
丛书文集 | 74篇 |
教育普及 | 1篇 |
理论方法论 | 2250篇 |
综合类 | 459篇 |
社会学 | 14181篇 |
统计学 | 5032篇 |
出版年
2023年 | 133篇 |
2022年 | 84篇 |
2021年 | 137篇 |
2020年 | 366篇 |
2019年 | 534篇 |
2018年 | 2184篇 |
2017年 | 2374篇 |
2016年 | 1600篇 |
2015年 | 459篇 |
2014年 | 625篇 |
2013年 | 3592篇 |
2012年 | 1067篇 |
2011年 | 1746篇 |
2010年 | 1497篇 |
2009年 | 1169篇 |
2008年 | 1315篇 |
2007年 | 1443篇 |
2006年 | 540篇 |
2005年 | 624篇 |
2004年 | 662篇 |
2003年 | 560篇 |
2002年 | 457篇 |
2001年 | 478篇 |
2000年 | 427篇 |
1999年 | 409篇 |
1998年 | 315篇 |
1997年 | 262篇 |
1996年 | 308篇 |
1995年 | 290篇 |
1994年 | 248篇 |
1993年 | 257篇 |
1992年 | 304篇 |
1991年 | 297篇 |
1990年 | 289篇 |
1989年 | 254篇 |
1988年 | 248篇 |
1987年 | 202篇 |
1986年 | 230篇 |
1985年 | 250篇 |
1984年 | 216篇 |
1983年 | 193篇 |
1982年 | 160篇 |
1981年 | 130篇 |
1980年 | 155篇 |
1979年 | 172篇 |
1978年 | 133篇 |
1977年 | 114篇 |
1976年 | 87篇 |
1975年 | 91篇 |
1974年 | 93篇 |
排序方式: 共有10000条查询结果,搜索用时 250 毫秒
231.
This paper studies optimum designs for linear models when the errors are heteroscedastic. Sufficient conditions are given
in order to obtainD-, A- andE-optimum designs for a complete regression model from partial optimum designs for some sub-parameters. A result about optimality
for a complete model from the optimality for the submodels is included.
Supported by Junta de Andalucía, research group FQM244. 相似文献
232.
The moderating role of maternal characteristics and maternal sensitivity on the concordance between maternal reports and laboratory observations of negative emotionality was examined. Participants were 90 primiparous mothers and their infants. Mothers completed questionnaires about remembered care from their own parents and their depressive symptoms prenatally, infant temperament (distress to novelty and distress to limitations), and depressive symptoms postnatally. Mothers and infants participated in a laboratory assessment of infant temperament (distress to novelty and limitations) and maternal sensitivity at 6 months postpartum. Several factors that moderate the degree of concordance between maternal reports and behavioral observations were identified, as predicted. Novelty concordance was higher when mothers reported having their emotional needs met in childhood and low prenatal depressive symptoms. Limitations concordance was higher when mothers were less sensitive during the observational tasks. Methodological and theoretical implications are discussed. 相似文献
233.
234.
Dwight R. Lee 《Journal of Labor Research》2003,24(3):437-446
Reverse mandated benefits is a government-mandated policy that requires employees to provide their employers with benefits
that workers would not provide otherwise. Of course, only those benefits would be mandated that are worth more to employers
than they cost, as determined by political authorities. My case for such a policy argues that it is at least as sensible as
policies mandating that employers provide benefits to their employees that would not be provided otherwise. 相似文献
235.
This paper investigates how individuals evaluate delayed outcomes with risky realization times. Under the discounted expected utility (DEU) model, such evaluations depend only on intertemporal preferences. We obtain several testable hypotheses using the DEU model as a benchmark and test these hypotheses in three experiments. In general, our results show that the DEU model is a poor predictor of intertemporal choice behavior under timing risk. We found that individuals are averse to timing risk and that they evaluate timing lotteries in a rank-dependent fashion. The main driver of timing risk aversion is nothing but probabilistic risk aversion that stems from the nonlinear treatment of probabilities. 相似文献
236.
237.
This paper is concerned with joint tests of non-nested models and simultaneous departures from homoskedasticity, serial independence and normality of the disturbance terms. Locally equivalent alternative models are used to construct joint tests since they provide a convenient way to incorporate more than one type of departure from the classical conditions. The joint tests represent a simple asymptotic solution to the “pre-testing” problem in the context of non-nested linear regression models. Our simulation results indicate that the proposed tests have good finite sample properties. 相似文献
238.
Fertility and Employment 总被引:3,自引:0,他引:3
239.
1. Research shows that many emergency workers are affected physically and emotionally by critical incident stress. 2. Debriefings conducted by trained team members are an effective method to mitigate the impact of critical incident stress. A debriefing is a structured, time-limited group intervention. 3. Cooperation among community agencies is essential for the development and effective functioning of a critical incident stress debriefing team. 4. Several teams in Illinois have organized to form a Critical Incident Stress Debriefing Network. The Illinois network is part of an international organization composed of critical incident stress debriefing providers. 相似文献
240.
This study examines the relationships among personal coping resources, social support, external coping resources, job stressors and job strains in a sample of 110 American Telephone and Telegraph employees undergoing a major organizational restructuring. The study expanded on a model suggested by Ashford (1988) by defining another category of coping resources that employees may draw upon to deal with the stressors and strains which occur during major organizational changes. External coping resources were defined as those which provided employees with a sense of 'vicarious control' in stressful situations. Results indicated that personal coping resources, social support and external coping resources had a direct effect upon job stressor and strain levels. No 'buffering' effect of these coplng resources was found. Hierarchical regression analyses indicated that external coping resources added to the prediction of job stressors and strains even when pertonal coping resources and social support were entered first into the prediction questions. 相似文献