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991.
Consumer Confidence Indexes can be sensibly used in economic and social research conducted in theoretical and methodological framework of social indicators research. They are good predictors of other attitudes, such as voting preferences. Voting preferences are determined much more strongly by expectations of changes in economic conditions than by evaluations of present situation. On the other hand, Consumer Sentiment Indexes — irrespective whether they concern future or present times — are correlated more strongly with leading than with coincident indexes of economic cycles. That proves very important role of predictions, expectations and hopes in attitude formation. 相似文献
992.
Measuring credibility of compensatory preference statements when trade-offs are interval determined 总被引:1,自引:0,他引:1
This paper studies how an overall fuzzy preference relation can be constructed in the compensatory context of the simple additive difference model, when imprecision on the trade-offs has to be taken into account. Three credibility indices of preferences are analysed and illustrated by a numerical example. Arguments are presented supporting the use of the third index, for which an interesting transitivity property (which was an open problem) is proved. 相似文献
993.
Lincoln H. Day 《Revue europeenne de demographie》1995,11(3):275-288
By the mid-1980s, fertility in most of the world's developed countries had declined to unprecedentedly low levels. Since then, it has declined still further in some, increased slightly in others, and fluctuated in still others. Irrespective of cause, these changes could not have occurred in the absence of substantial control over childbearing.While future increases and decreases are both possible, it is argued that, contrary to the usual demographic expectations for populations exercising substantial control over fertility, fertility in most of these countries will increase to approximate replacement levels and then undergo only minor fluctuations around these levels thereafter. 相似文献
994.
Robert F. Nau 《Journal of Risk and Uncertainty》1995,10(1):71-91
This article explores the extent to which a decision maker's probabilities can be measured separately from his/her utilities by observing his/her acceptance of small monetary gambles. Only a partial separation is achieved: the acceptable gambles are partitioned into a set of belief gambles, which reveals probabilities distorted by marginal utilities for money, and a set of preference gambles, which reveals utilities reciprocally distorted by marginal utilities for money. However, the information in these gambles still enables us to solve the decision maker's problem: his/her utility-maximizing decision is the one that avoids arbitrage (i.e., incoherence or Dutch books). 相似文献
995.
Drawing households and other living spaces in the process of assessment and psychotherapy 总被引:1,自引:1,他引:0
This paper introduces a drawing technique developed by the author for use in the assessment and treatment of individuals and families. The client is invited to draw a floor plan of his or her home or apartment, or an aerial view of un outdoor area. The drawing is then discussed and considered as a means of understanding critical elements of the experience of life space. The material derived is discussed from the eerspectives of family systems, psychodynamic, and abuse treatment theories, with special reference to notions of family structure, boundary, the self, and memory. Emphasis is placed on the actual physical layout of the home, as well as the subjective experience of it. Applications of the drawing technique for exploring memories are illustrated. Case examples are presented from clinical trials with children and adults in residential treatment, inpatient, and outpatient settings.The Heller Financial Corporation generously supports the development of household and spatial drawings for treatment and prevention. A version of this paper was presented at the 43rd Annual Meeting of the American Association of Psychiatric Services for Children, New Orleans, February 26, 1992. The author wishes to thank Robert B. Bloom, Ph.D., Excutive Director of JCB, for supporting the development of ideas and techniques discribed in this paper. 相似文献
996.
Suppose that social welfare function f satisfies the Pareto condition and has complete and transitive values. On a domain satisfying the free quadruple property, if the outcome set X has m< outcomes, then the set of pairs of distinct alternatives on which f satisfies both independence and nondictatorship contains at most the fraction 2/m of all pairs. On a domain satisfying the free six-tuple property, if X is a subset of Euclidean space then the set of pairs on which f satisfies both independence and nondictatorship has Lebesgue measure zero.Campbell's research was financed by the National Science Foundation, grant SES 9209039. 相似文献
997.
"This article examines the probable effects of the North American Free Trade Agreement (NAFTA) on migration from Mexico to the United States, disputing the view that expansion of jobs in Mexico could rapidly reduce undocumented migration. To the extent that NAFTA causes Mexican export agriculture to expand, migration to the United States will increase rather than decrease in the short run. Data collected in both California and the Mexican State of Baja California show that indigenous migrants from southern Mexico typically first undertake internal migration, which lowers the costs and risks of U.S. migration. Two features of employment in export agriculture were found to be specially significant in lowering the costs of U.S. migration: first, working in export agriculture exposes migrants to more diverse social networks and information about U.S. migration; second, agro-export employment in northern Mexico provides stable employment, albeit low-wage employment, for some members of the family close to the border (especially women and children) while allowing other members of the family to assume the risks of U.S. migration." 相似文献
998.
James M. Robins 《Lifetime data analysis》1995,1(3):241-254
Consider a randomized trial in which time to the occurrence of a particular disease, say pneumocystis pneumonia in an AIDS trial or breast cancer in a mammographic screening trial, is the failure time of primary interest. Suppose that time to disease is subject to informative censoring by the minimum of time to death, loss to and end of follow-up. In such a trial, the censoring time is observed for all study subjects, including failures. In the presence of informative censoring, it is not possible to consistently estimate the effect of treatment on time to disease without imposing additional non-identifiable assumptions. The goals of this paper are to specify two non-identifiable assumptions that allow one to test for and estimate an effect of treatment on time to disease in the presence of informative censoring. In a companion paper (Robins, 1995), we provide consistent and reasonably efficient semiparametric estimators for the treatment effect under these assumptions. In this paper we largely restrict attention to testing. We propose tests that, like standard weighted-log-rank tests, are asymptotically distribution-free -level tests under the null hypothesis of no causal effect of treatment on time to disease whenever the censoring and failure distributions are conditionally independent given treatment arm. However, our tests remain asymptotically distribution-free -level tests in the presence of informative censoring provided either of our assumptions are true. In contrast, a weighted log-rank test will be an -level test in the presence of informative censoring only if (1) one of our two non-identifiable assumptions hold, and (2) the distribution of time to censoring is the same in the two treatment arms. We also extend our methods to studies of the effect of a treatment on the evolution over time of the mean of a repeated measures outcome, such as CD-4 count. 相似文献
999.
A controlled exit-poll experiment on Election Day (November3, 1992) shows that refusals to answer questions and other evasiveforms of responding were significantly lower when respondentswere given a self-administered "secret-ballot" questionnairethan when they were interviewed face-to-face. While there weresome suggestive interactions of this mode-of-data collectioneffect with age and sex, and with the partisan atmosphere ofthe precinct in which the interviews were conducted, they wereborderline in significance, inconsistent in pattern, or difficuitto interpret. More important, comparisons with official electionreturns (the truth) indicated that the secret-ballot techniquewas more accurate than were face-to-face interviews in estimatingthe final outcome on the most socially sensitive of three self-reportedvotes: a vote for or against a tax levy for elderly services.Using a genuine secret ballot in the tradition of the olderGallup preelection polls can thus increase the validity of self-reportsin exit polls today. 相似文献
1000.
An evaluation of population projection errors for census tracts 总被引:1,自引:0,他引:1
"In this article we evaluate the accuracy and bias of projections of total population and population by age group for census tracts in three counties in Florida. We use [U.S. census] data from 1970 and 1980 and several simple extrapolation techniques to produce projections for 1990; we then compare these projections with 1990 census counts and evaluate the differences. For the total sample, we find mean absolute errors of 17%-20% for the three most accurate techniques for projecting total population and find no indication of overall bias. For individual age groups, mean absolute errors range from 20%-29%." This is a revised version of a paper presented at the 1993 Annual Meeting of the Population Association of America. 相似文献