全文获取类型
收费全文 | 185891篇 |
免费 | 5016篇 |
国内免费 | 1952篇 |
专业分类
管理学 | 4126篇 |
劳动科学 | 34篇 |
民族学 | 3080篇 |
人才学 | 29篇 |
人口学 | 2493篇 |
丛书文集 | 25180篇 |
理论方法论 | 7867篇 |
综合类 | 136647篇 |
社会学 | 7059篇 |
统计学 | 6344篇 |
出版年
2024年 | 310篇 |
2023年 | 940篇 |
2022年 | 1314篇 |
2021年 | 1570篇 |
2020年 | 2017篇 |
2019年 | 1947篇 |
2018年 | 1958篇 |
2017年 | 2429篇 |
2016年 | 2658篇 |
2015年 | 3643篇 |
2014年 | 8988篇 |
2013年 | 10671篇 |
2012年 | 11197篇 |
2011年 | 13287篇 |
2010年 | 10808篇 |
2009年 | 11099篇 |
2008年 | 11667篇 |
2007年 | 14547篇 |
2006年 | 14568篇 |
2005年 | 13478篇 |
2004年 | 12591篇 |
2003年 | 12414篇 |
2002年 | 9999篇 |
2001年 | 8398篇 |
2000年 | 4721篇 |
1999年 | 1349篇 |
1998年 | 719篇 |
1997年 | 576篇 |
1996年 | 479篇 |
1995年 | 410篇 |
1994年 | 299篇 |
1993年 | 265篇 |
1992年 | 223篇 |
1991年 | 191篇 |
1990年 | 106篇 |
1989年 | 127篇 |
1988年 | 77篇 |
1987年 | 47篇 |
1986年 | 47篇 |
1985年 | 109篇 |
1984年 | 147篇 |
1983年 | 97篇 |
1982年 | 98篇 |
1981年 | 63篇 |
1980年 | 59篇 |
1979年 | 57篇 |
1978年 | 53篇 |
1977年 | 18篇 |
1976年 | 13篇 |
1975年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
981.
王力媛 《湖北民族学院学报(哲学社会科学版)》2006,24(5):36-38
民族工作必须体现时代的精神,党中央在我国社会主义建设的关键时期提出的各民族需“共同团结奋斗,共同繁荣发展”,顺应了时代的要求。少数民族的发展只有在建设中国特色社会主义的共同事业中才能逐步解决。 相似文献
982.
983.
Cathy W. S. Chen Hong Than-Thi Mike K. P. So 《Journal of Statistical Computation and Simulation》2019,89(2):191-210
This paper proposes a new hysteretic vector autoregressive (HVAR) model in which the regime switching may be delayed when the hysteresis variable lies in a hysteresis zone. We integrate an adapted multivariate Student-t distribution from amending the scale mixtures of normal distributions. This HVAR model allows for a higher degree of flexibility in the degrees of freedom for each time series. We use the proposed model to test for a causal relationship between any two target time series. Using posterior odds ratios, we overcome the limitations of the classical approach to multiple testing. Both simulated and real examples herein help illustrate the suggested methods. We apply the proposed HVAR model to investigate the causal relationship between the quarterly growth rates of gross domestic product of United Kingdom and United States. Moreover, we check the pairwise lagged dependence of daily PM2.5 levels in three districts of Taipei. 相似文献
984.
Yunquan Song Yanji Zhu Xiuli Wang Lu Lin 《Journal of Statistical Computation and Simulation》2019,89(17):3196-3212
Nonresponse is a very common phenomenon in survey sampling. Nonignorable nonresponse – that is, a response mechanism that depends on the values of the variable having nonresponse – is the most difficult type of nonresponse to handle. This article develops a robust estimation approach to estimating equations (EEs) by incorporating the modelling of nonignorably missing data, the generalized method of moments (GMM) method and the imputation of EEs via the observed data rather than the imputed missing values when some responses are subject to nonignorably missingness. Based on a particular semiparametric logistic model for nonignorable missing response, this paper proposes the modified EEs to calculate the conditional expectation under nonignorably missing data. We can apply the GMM to infer the parameters. The advantage of our method is that it replaces the non-parametric kernel-smoothing with a parametric sampling importance resampling (SIR) procedure to avoid nonparametric kernel-smoothing problems with high dimensional covariates. The proposed method is shown to be more robust than some current approaches by the simulations. 相似文献
985.
Carlos J. Pérez-González Arturo J. Fernández 《Journal of Statistical Computation and Simulation》2019,89(13):2489-2504
An accurate procedure is proposed to calculate approximate moments of progressive order statistics in the context of statistical inference for lifetime models. The study analyses the performance of power series expansion to approximate the moments for location and scale distributions with high precision and smaller deviations with respect to the exact values. A comparative analysis between exact and approximate methods is shown using some tables and figures. The different approximations are applied in two situations. First, we consider the problem of computing the large sample variance–covariance matrix of maximum likelihood estimators. We also use the approximations to obtain progressively censored sampling plans for log-normal distributed data. These problems illustrate that the presented procedure is highly useful to compute the moments with precision for numerous censoring patterns and, in many cases, is the only valid method because the exact calculation may not be applicable. 相似文献
986.
Mohammad Reza Mahmoudi Marziyeh Mahmoudi Abbas Pak 《Journal of Statistical Computation and Simulation》2019,89(12):2280-2292
Classifying several regression models fitted on a dataset is one of the most problems in data analysis. In other words, scientists are interested in comparing several regression models that can be used for a dataset. In this paper, an approach will be used to compare and classify several dependent regression models. Then the performance of the proposed method is investigated using simulation study and real example. 相似文献
987.
Hadi Alizadeh Noughabi 《Journal of Statistical Computation and Simulation》2019,89(10):1914-1934
We propose here a general statistic for the goodness of fit test of statistical distributions. The proposed statistic is constructed based on an estimate of Kullback–Leibler information. The proposed test is consistent and the limiting distribution of the test statistic is derived. Then, the established results are used to introduce goodness of fit tests for the normal, exponential, Laplace and Weibull distributions. A simulation study is carried out for examining the power of the proposed test and to compare it with those of some existing procedures. Finally, some illustrative examples are presented and analysed, and concluding comments are made. 相似文献
988.
The traditional estimation of higher order co-moments of non-normal random variables by the sample analog of the expectation faces a curse of dimensionality, as the number of parameters increases steeply when the dimension increases. Imposing a factor structure on the process solves this problem; however, it leads to the challenging task of selecting an appropriate factor model. This paper contributes by proposing a test that exploits the following feature: when the factor model is correctly specified, the higher order co-moments of the unexplained return variation are sparse. It recommends a general to specific approach for selecting the factor model by choosing the most parsimonious specification for which the sparsity assumption is satisfied. This approach uses a Wald or Gumbel test statistic for testing the joint statistical significance of the co-moments that are zero when the factor model is correctly specified. The asymptotic distribution of the test is derived. An extensive simulation study confirms the good finite sample properties of the approach. This paper illustrates the practical usefulness of factor selection on daily returns of random subsets of S&P 100 constituents. 相似文献
989.
Abdelbaset Abdalla 《Journal of Statistical Computation and Simulation》2019,89(14):2782-2800
Despite the popularity and importance, there is limited work on modelling data which come from complex survey design using finite mixture models. In this work, we explored the use of finite mixture regression models when the samples were drawn using a complex survey design. In particular, we considered modelling data collected based on stratified sampling design. We developed a new design-based inference where we integrated sampling weights in the complete-data log-likelihood function. The expectation–maximisation algorithm was developed accordingly. A simulation study was conducted to compare the new methodology with the usual finite mixture of a regression model. The comparison was done using bias-variance components of mean square error. Additionally, a simulation study was conducted to assess the ability of the Bayesian information criterion to select the optimal number of components under the proposed modelling approach. The methodology was implemented on real data with good results. 相似文献
990.
Zoran Vidović 《Journal of applied statistics》2019,46(4):715-724
The modified Weibull distribution can be used quite effectively to model complex data from mechanical engineering or survival analysis studies that posses a monotonic or a bathtub-shape hazard rate. In this paper, we study the MLEs of the parameters of a modified Weibull distribution model in the presence of upper kth record values. The existence and uniqueness of the MLEs are proven in this case. Real data analysis is performed for illustrative purposes. 相似文献