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191.
Using the 1970 1/1,000 Public Use Sample of the U.S. population, the relationships of the closed and open birth intervals with parity and mother's age, with parity and marital duration, and with children ever born/marital duration and mother's age are analyzed. These findings both replicate and expand on Srinivasan's earlier research on the open interval. The open interval is more sensitive as an index of marital fertility when marital duration and parity are controlled than when mother's age and parity are controlled.  相似文献   
192.
This text addresses the critiques from the Urban Institute and other immigrant advocacy groups concerning the findings of an earlier study, The Cost of Immigration released in the summer of 1993. That study showed that the public costs associated withimmigrants settling here since 1970 amounted, in 1992, to $42.5 billion more in services and assistance than the $20.2 billion which immigrants paid in taxes (Huddle, 1993). The updated assessment takes into account previously unavailable figures and revises some methods and assumptions used in the earlier work. The updated bottom line is fully consistent with initial findings on immigrant costs for 1992.  相似文献   
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The influence of the family on premarital sexual attitudes and behavior   总被引:6,自引:1,他引:6  
This research has expanded our understanding of the determinants of adolescent sexuality in several directions. We have used a study of mothers and children to construct and estimate a model of the intergenerational transmission of sexual attitudes and behavior. With data collected from both mothers and children, we were able to proceed further than most past research and to consider both the attitudes and behaviors of mothers as reported by the mothers themselves. These data permitted an investigation of the determinants of maternal attitudes concerning adolescent sexuality as well as an examination of the influences of the attitudes and experiences of mothers on the attitudes, perceptions, and behavior of children. Obviously, limiting the study to white families prevents generalization of our findings to other subgroups of the population. The findings demonstrate the importance and relevance of parental and adolescent attitudes in understanding adolescent sexuality. Premarital sexuality is a salient issue to both young people and their parents. There are, however, very important and substantial differences in the attitudes of parents and children. On average, the attitudes of young people today are much less restrictive than those of their parents, reflecting either life cycle differences or the impact of social change. The intergenerational difference is recognized by young people themselves and probably affects the ability of parents to assist their maturing children in adjusting to and dealing with their sexuality--a difficulty likely to be reflected in the relative lack of success sexually active young people have in preventing pregnancy. Our findings also add to the research literature in demonstrating that although children, on average, have more permissive attitudes than their parents, the attitudes of individual parents tend to be reflected in the attitudes of individual children. Children whose mothers have less restrictive attitudes have, on average, less restrictive attitudes themselves. Further, the attitudes of mothers are also reflected in the behavior of their children, so on average, mothers with more permissive attitudes have children who are more sexually active. The influence of maternal attitudes, however, is stronger for children's attitudes than for their behavior. Of course, variability in children's attitudes and behavior--and even their perceptions of maternal attitudes--can only be partially explained by the attitudes of their mothers; but presumably, if the attitudes of other important family members, including fathers and siblings, were known, the prediction of adolescent attitudes would improve.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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This article, sets out a series of principles for pension design rooted in economic theory: pension systems have multiple objectives, analysis should consider the pension system as a whole, analysis should be framed in a second-best context, different systems share risks differently, and systems have different effects by generation and by gender. That discussion is reinforced by identification of a series of widespread analytical errors — errors that appear in World Bank work, but by no means only in World Bank work: tunnel vision, improper use of first-best analysis, improper use of steady-state analysis, incomplete analysis of implicit pension debt, incomplete analysis of the impact of funding (including excessive focus on financial flows, failure to consider how funding is generated, and improper focus on the type of asset in trust funds), and ignoring distributional effects. The second part of the article considers implications for policy: there is no single best pension design, earlier retirement does little or nothing to reduce unemployment, unsustainable pension promises need to be addressed directly, a move from pay-as-you-go towards funding in a mandatory system may or may not be welfare improving, and implementation matters — policy design that exceeds a country's capacity to implement it is bad policy design. We illustrate the ranges of designs of pension systems that fit the fiscal and institutional capacity constraints typical at different levels of economic development. The potential gains from simplicity imply that a country capable of implementing an administratively demanding plan does not necessarily gain from doing so. New Zealand has a simple pension system through choice, not constraint.  相似文献   
198.
The success of interventions designed to address important issues in social and medical science is best addressed by randomized experiments. With human beings there are often complications, however, such as noncompliance and missing data. Such complications are often addressed by statistically invalid methods of analysis, in particular, intention-to-treat and per-protocol analyses. Here we address these two complications using a statistically valid approach based on principal stratification with a fully Bayesian analysis. This analysis is applied to a randomized trial of a potentially important intervention designed to reduce the transmission of bacterial colonization between mothers and their infants through vaginal delivery in South Africa: the Prevention of Perinatal Sepsis (PoPs).  相似文献   
199.
This paper considers regression models for cross‐section data that exhibit cross‐section dependence due to common shocks, such as macroeconomic shocks. The paper analyzes the properties of least squares (LS) estimators in this context. The results of the paper allow for any form of cross‐section dependence and heterogeneity across population units. The probability limits of the LS estimators are determined, and necessary and sufficient conditions are given for consistency. The asymptotic distributions of the estimators are found to be mixed normal after recentering and scaling. The t, Wald, and F statistics are found to have asymptotic standard normal, χ2, and scaled χ2 distributions, respectively, under the null hypothesis when the conditions required for consistency of the parameter under test hold. However, the absolute values of t, Wald, and F statistics are found to diverge to infinity under the null hypothesis when these conditions fail. Confidence intervals exhibit similarly dichotomous behavior. Hence, common shocks are found to be innocuous in some circumstances, but quite problematic in others. Models with factor structures for errors and regressors are considered. Using the general results, conditions are determined under which consistency of the LS estimators holds and fails in models with factor structures. The results are extended to cover heterogeneous and functional factor structures in which common factors have different impacts on different population units.  相似文献   
200.
We present two theorems that yield necessary and sufficient conditions for first- and second-degree stochastic dominance deteriorations of background risk to increase risk aversion with respect to foreground risk. We require that any change in a foreground risk that is undesirable remains so after a background risk changes in a way that is either unfair, undesirable in the sense of reducing expected utility, or undesirable in the sense of increasing expected marginal utility. Our results thus characterize utility functions that are, respectively, vulnerable, proper, or standard with respect to changes in background risk.
Arthur SnowEmail:
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