全文获取类型
收费全文 | 1976篇 |
免费 | 65篇 |
专业分类
管理学 | 261篇 |
民族学 | 13篇 |
人口学 | 179篇 |
丛书文集 | 13篇 |
理论方法论 | 208篇 |
综合类 | 13篇 |
社会学 | 1151篇 |
统计学 | 203篇 |
出版年
2023年 | 26篇 |
2022年 | 18篇 |
2021年 | 21篇 |
2020年 | 51篇 |
2019年 | 49篇 |
2018年 | 67篇 |
2017年 | 104篇 |
2016年 | 92篇 |
2015年 | 42篇 |
2014年 | 79篇 |
2013年 | 288篇 |
2012年 | 88篇 |
2011年 | 99篇 |
2010年 | 69篇 |
2009年 | 70篇 |
2008年 | 80篇 |
2007年 | 72篇 |
2006年 | 82篇 |
2005年 | 59篇 |
2004年 | 74篇 |
2003年 | 52篇 |
2002年 | 46篇 |
2001年 | 31篇 |
2000年 | 27篇 |
1999年 | 35篇 |
1998年 | 25篇 |
1997年 | 27篇 |
1996年 | 22篇 |
1995年 | 19篇 |
1994年 | 13篇 |
1993年 | 12篇 |
1992年 | 16篇 |
1991年 | 19篇 |
1990年 | 9篇 |
1989年 | 15篇 |
1988年 | 12篇 |
1987年 | 16篇 |
1986年 | 11篇 |
1985年 | 12篇 |
1984年 | 13篇 |
1983年 | 13篇 |
1982年 | 11篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1974年 | 5篇 |
1969年 | 3篇 |
排序方式: 共有2041条查询结果,搜索用时 15 毫秒
31.
AbstractIn this installment of “Conversations,” Dominic Boyer, Cymene Howe, and Marcel LaFlamme, of the Cultural Anthropology editorial team, discuss the ins and outs of publishing a gold open access journal in the field of anthropology. Highlights of the discussion include Cultural Anthropology’s move to open access, the ethics of open access, the growth of international readership, ongoing publishing challenges in open access, and the role libraries can play with open access publishing. 相似文献
32.
This article describes estimation and inference procedures for the parameters of the Box-Cox and foided-power transformations in repeated measures and growth curve models. Procedures for computing maximum likelihood estimates of the transformation and covariance parameters under several covanance structures (omnibus sphericity, local sphericity, and unstructured) are described. Lack of fit statistics and hypothesis tests for comparing these structures also are described. The procedures are illustrated on three data sets. Software for performing the analyses in the SAS System is described and is available from the authors. 相似文献
33.
34.
A problem of estimating the integral of a squared regression function and of its squared derivatives has been addressed in a number of papers. For the case of a heteroscedastic model where smoothness of the underlying regression function, the design density, and the variance of errors are known, the asymptotically sharp minimax lower bound and a sharp estimator were found in Pastuchova & Khasminski (1989). However, there are apparently no results on the either rate optimal or sharp optimal adaptive, or data-driven, estimation when neither the degree of regression function smoothness nor design density, scale function and distribution of errors are known. After a brief review of main developments in non-parametric estimation of non-linear functionals, we suggest a simple adaptive estimator for the integral of a squared regression function and its derivatives and prove that it is sharp-optimal whenever the estimated derivative is sufficiently smooth. 相似文献
35.
Data from the Panel Study of Income Dynamics and three decennial US censuses are used to examine the influence of metropolitan-area characteristics on black and white households’ propensity to move into poor versus nonpoor neighborhoods. We find that a nontrivial portion of the variance in the odds of moving to a poor rather to a nonpoor neighborhood exists between metropolitan areas. Net of established individual-level predictors of inter-neighborhood migration, black and white households are more likely to move to a poor or extremely poor tract rather than to a nonpoor tract in metropolitan areas containing many poor neighborhoods and a paucity of recently-built housing in nonpoor areas. Blacks are especially likely to move to a poor tract in metropolitan areas characterized by high levels of racial residential segregation and in which poor tracts have a sizeable concentration of blacks. White households are more likely to move to a poor than to a nonpoor tract in metropolitan areas that have comparatively few African Americans. 相似文献
36.
Utilizing the stress process and life course perspectives, we investigated the influence of non-spousal social support on the associations between marital quality, physical disability, and loneliness among married older adults. Using data from the National Social Life, Health, and Aging Project (NSHAP), we found that the association between physical disability and loneliness was partially accounted for by the fact that physical disability was associated with less supportive nonmarital relationships. While physically-disabled older adults in higher-quality marriages were buffered from loneliness, supportive non-martial relationships did not offset elevated loneliness among those in low-quality marriages. These associations were largely similar for men and women. Thus, although both marital and nonmarital relationships are important for loneliness, when confronted with a stressor such as disablement it is the marital relationship alone that matters. 相似文献
37.
38.
39.
Alexander Torgovitsky 《Econometrica : journal of the Econometric Society》2015,83(3):1185-1197
I consider nonparametric identification of nonseparable instrumental variables models with continuous endogenous variables. If both the outcome and first stage equations are strictly increasing in a scalar unobservable, then many kinds of continuous, discrete, and even binary instruments can be used to point‐identify the levels of the outcome equation. This contrasts sharply with related work by Imbens and Newey, 2009 that requires continuous instruments with large support. One implication is that assumptions about the dimension of heterogeneity can provide nonparametric point‐identification of the distribution of treatment response for a continuous treatment in a randomized controlled experiment with partial compliance. 相似文献
40.
This study examined whether the efficacy of keepin' it REAL, a model program for substance use prevention in schools, was moderated by gender, ethnicity, and acculturation. Gender differences in program efficacy may arise through boys' higher risk of drug use, inadequate attention to girls' developmental issues, or cultural factors like polarized gender expectations. Data came from a randomized trial in 35 Phoenix, Arizona, middle schools involving 4,622 mostly Latino 7th graders. Using multi-level mixed models and multiple imputation missing techniques, results for the total sample showed no gender differences in program effects on recent substance use, but the program was more effective in fostering boys' than girls' anti-drug norms. Subgroup analyses demonstrated several more beneficial program effects for boys than girls (less alcohol and cigarette use and stronger anti-drug norms), but only among less acculturated Latinos. There were no gender differences in program effects among more acculturated Latinos, nor among non-Latino whites. 相似文献