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81.
We examine the challenges of governance facing organizations that pursue a social mission through the use of market mechanisms. These hybrid organizations, often referred to as social enterprises, combine aspects of both charity and business at their core. In this paper we distinguish between two ideal types of such hybrids, differentiated and integrated, and we conceptualize two key challenges of governance they face: accountability for dual performance objectives and accountability to multiple principal stakeholders. We revisit the potential and limitations of recently introduced legal forms to address these challenges. We then theorize about the importance of organizational governance and the role of governing boards in particular, in prioritizing and aligning potentially conflicting objectives and interests in order to avoid mission drift and to maintain organizational hybridity in social enterprises. Finally, we discuss future research directions and the implications of this work for rethinking traditional categories of organizations, namely business and charity.  相似文献   
82.
自然界的有生命之物,以其不同的形状、色彩、气息和动静之态,而有着不同的审美价值.它们的美是生命之美.中国花鸟画不以再现自然对象的外形为目的,而以思想、情感、意趣等生命现象的高级形式反映在作品中.作者根据主观的审美理想和自我生命的节律加以重新创造,使其固定为物化状态,给人以美的滋养.  相似文献   
83.
文章通过分析毕业实习中的问题 ,探讨如何加强美术师范学生的素质教育 ,提高学生综合素质水平  相似文献   
84.
关于汉族、达斡尔族家庭教养方式的跨文化比较研究   总被引:3,自引:0,他引:3  
本研究采取的是同一地区不同民族跨文化比较研究,目的是通过汉族和达斡尔族学生家长的取样测试,揭示汉族、达斡尔族家庭教养方式的民族差异,探讨有关影响因素,为合理、有效的家庭教育提供科学依据。  相似文献   
85.
晋西北山曲、陕北信天游、内蒙古原绥远地区的爬山歌 ,体例相同 ,词曲相近 ,共同构成我国北方单独的一个民歌圈 ,其生成与清代民国时期的“走西口”移民运动密切相关。在“走西口”过程中 ,晋西北、陕北人口大批向河套及大青山前后地区移居 ,形成以山西河曲、保德人和陕西府谷、神木、榆林人为核心的“河府移民圈” ,人口同源支持了民歌共性。长盛不衰的雁行式“走西口”生活 ,不断刺激着民歌的创造与发达 ,使三地民歌的交汇共生走向高潮 ,在发展中推动了三地民歌的同质化过程。  相似文献   
86.
Clinical trials are often designed to compare continuous non‐normal outcomes. The conventional statistical method for such a comparison is a non‐parametric Mann–Whitney test, which provides a P‐value for testing the hypothesis that the distributions of both treatment groups are identical, but does not provide a simple and straightforward estimate of treatment effect. For that, Hodges and Lehmann proposed estimating the shift parameter between two populations and its confidence interval (CI). However, such a shift parameter does not have a straightforward interpretation, and its CI contains zero in some cases when Mann–Whitney test produces a significant result. To overcome the aforementioned problems, we introduce the use of the win ratio for analysing such data. Patients in the new and control treatment are formed into all possible pairs. For each pair, the new treatment patient is labelled a ‘winner’ or a ‘loser’ if it is known who had the more favourable outcome. The win ratio is the total number of winners divided by the total numbers of losers. A 95% CI for the win ratio can be obtained using the bootstrap method. Statistical properties of the win ratio statistic are investigated using two real trial data sets and six simulation studies. Results show that the win ratio method has about the same power as the Mann–Whitney method. We recommend the use of the win ratio method for estimating the treatment effect (and CI) and the Mann–Whitney method for calculating the P‐value for comparing continuous non‐Normal outcomes when the amount of tied pairs is small. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
87.
This paper provides a Bayesian estimation procedure for monotone regression models incorporating the monotone trend constraint subject to uncertainty. For monotone regression modeling with stochastic restrictions, we propose a Bayesian Bernstein polynomial regression model using two-stage hierarchical prior distributions based on a family of rectangle-screened multivariate Gaussian distributions extended from the work of Gurtis and Ghosh [7 S.M. Curtis and S.K. Ghosh, A variable selection approach to monotonic regression with Bernstein polynomials, J. Appl. Stat. 38 (2011), pp. 961976. doi: 10.1080/02664761003692423[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]]. This approach reflects the uncertainty about the prior constraint, and thus proposes a regression model subject to monotone restriction with uncertainty. Based on the proposed model, we derive the posterior distributions for unknown parameters and present numerical schemes to generate posterior samples. We show the empirical performance of the proposed model based on synthetic data and real data applications and compare the performance to the Bernstein polynomial regression model of Curtis and Ghosh [7 S.M. Curtis and S.K. Ghosh, A variable selection approach to monotonic regression with Bernstein polynomials, J. Appl. Stat. 38 (2011), pp. 961976. doi: 10.1080/02664761003692423[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]] for the shape restriction with certainty. We illustrate the effectiveness of our proposed method that incorporates the uncertainty of the monotone trend and automatically adapts the regression function to the monotonicity, through empirical analysis with synthetic data and real data applications.  相似文献   
88.
In this paper, we consider the problem of making statistical inference for a truncated normal distribution under progressive type I interval censoring. We obtain maximum likelihood estimators of unknown parameters using the expectation-maximization algorithm and in sequel, we also compute corresponding midpoint estimates of parameters. Estimation based on the probability plot method is also considered. Asymptotic confidence intervals of unknown parameters are constructed based on the observed Fisher information matrix. We obtain Bayes estimators of parameters with respect to informative and non-informative prior distributions under squared error and linex loss functions. We compute these estimates using the importance sampling procedure. The highest posterior density intervals of unknown parameters are constructed as well. We present a Monte Carlo simulation study to compare the performance of proposed point and interval estimators. Analysis of a real data set is also performed for illustration purposes. Finally, inspection times and optimal censoring plans based on the expected Fisher information matrix are discussed.  相似文献   
89.
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   
90.
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   
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