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21.
What does sociology have to contribute to our understanding of terrorism? As scholars of gender and the Far Right, we believe that we have much to offer the current debates. In this article, we focus both on contemporary cases of terrorism, the attacks of September 11 and the Oklahoma City bombing, and terrorist movements as gendered: as enactments of masculinity. In particular, we focus on the contemporary white supremacist movement, the most dangerous domestic terrorist threat faced by the USA. We suggest that the ideology and organization of many terrorist groups are saturated with gendered meanings, both as the analytic prism through which they view their situation, and also as a means of political mobilization. 相似文献
22.
Craig H. Mallinckrodt John G. Watkin Geert Molenberghs Raymond J. Carroll 《Pharmaceutical statistics》2004,3(3):161-169
Missing data, and the bias they can cause, are an almost ever‐present concern in clinical trials. The last observation carried forward (LOCF) approach has been frequently utilized to handle missing data in clinical trials, and is often specified in conjunction with analysis of variance (LOCF ANOVA) for the primary analysis. Considerable advances in statistical methodology, and in our ability to implement these methods, have been made in recent years. Likelihood‐based, mixed‐effects model approaches implemented under the missing at random (MAR) framework are now easy to implement, and are commonly used to analyse clinical trial data. Furthermore, such approaches are more robust to the biases from missing data, and provide better control of Type I and Type II errors than LOCF ANOVA. Empirical research and analytic proof have demonstrated that the behaviour of LOCF is uncertain, and in many situations it has not been conservative. Using LOCF as a composite measure of safety, tolerability and efficacy can lead to erroneous conclusions regarding the effectiveness of a drug. This approach also violates the fundamental basis of statistics as it involves testing an outcome that is not a physical parameter of the population, but rather a quantity that can be influenced by investigator behaviour, trial design, etc. Practice should shift away from using LOCF ANOVA as the primary analysis and focus on likelihood‐based, mixed‐effects model approaches developed under the MAR framework, with missing not at random methods used to assess robustness of the primary analysis. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
23.
H. Haario M. Laine M. Lehtinen E. Saksman J. Tamminen 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2004,66(3):591-607
Summary. We discuss the inversion of the gas profiles (ozone, NO3 , NO2 , aerosols and neutral density) in the upper atmosphere from the spectral occultation measurements. The data are produced by the 'Global ozone monitoring of occultation of stars' instrument on board the Envisat satellite that was launched in March 2002. The instrument measures the attenuation of light spectra at various horizontal paths from about 100 km down to 10–20 km. The new feature is that these data allow the inversion of the gas concentration height profiles. A short introduction is given to the present operational data management procedure with examples of the first real data inversion. Several solution options for a more comprehensive statistical inversion are presented. A direct inversion leads to a non-linear model with hundreds of parameters to be estimated. The problem is solved with an adaptive single-step Markov chain Monte Carlo algorithm. Another approach is to divide the problem into several non-linear smaller dimensional problems, to run parallel adaptive Markov chain Monte Carlo chains for them and to solve the gas profiles in repetitive linear steps. The effect of grid size is discussed, and we present how the prior regularization takes the grid size into account in a way that effectively leads to a grid-independent inversion. 相似文献
24.
25.
For testing the fit of the inverse Gaussian distribution with unknown parameters, the empirical distribution-function statistic A2 is studied. Two procedures are followed in constructing the test statistic; they yield the same asymptotic distribution. In the first procedure the parameters in the distribution function are directly estimated, and in the second the distribution function is estimated by its Rao-Blackwell distribution estimator. A table is given for the asymptotic critical points of A2. These are shown to depend only on the ratio of the unknown parameters. An analysis is provided of the effect of estimating the ratio to enter the table for A2. This analysis enables the proposal of the complete operating procedure, which is sustained by a Monte Carlo study. 相似文献
26.
27.
Julian L. Simon 《Journal of Labor Research》1992,13(1):73-78
VII. Conclusion The number of immigrants now coming to the United States is proportionally only a fraction of the number that came in earlier
years, and there is nothing in those numbers to suggest a difficult absorption burden. Immigrants, both legal and illegal,
more than pay for the services they use with the taxes they pay, leaving a considerable net surplus that benefits American
citizens. Immigrants raise productivity and do not cause an observable amount of unemployment of citizens. Admitting far more
immigrants into the country than the law now allows would have positive effects on the incomes of citizens, and would enhance
the continuing vitality of the United States. 相似文献
28.
In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse. 相似文献
29.
30.
Michael H. LeRoy 《Journal of Labor Research》1992,13(4):371-379
One hundred and sixty-four elite union leaders in the United States completed a survey to assess the condition of the American
labor movement and the factors affecting it. The respondents included high-level international union and state federation
officers, central labor presidents, and 58 shop stewards. This study compares the responses of these labor officials and finds
that they have similar, negative assessments of the condition of the American labor movement. The study also finds that these
leaders agree that the most important factors affecting the labor movement are collective bargaining rights, union leadership,
union member solidarity, and the NLRB. 相似文献