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51.
Abstract

Confidence sets, p values, maximum likelihood estimates, and other results of non-Bayesian statistical methods may be adjusted to favor sampling distributions that are simple compared to others in the parametric family. The adjustments are derived from a prior likelihood function previously used to adjust posterior distributions.  相似文献   
52.
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion.  相似文献   
53.
当前我国收入分配不公的原因、影响及对策   总被引:1,自引:0,他引:1  
居民收入分配不公,是我国当前面临的一个十分突出的社会问题,其原因即有合理因素,也有非合理因素,但更多的是后者。收入分配不公问题若任其长期存在,必然会严重危害政治与社会的稳定,阻碍经济的健康、持续发展。因此,对于这一问题必须及时有效的加以治理。  相似文献   
54.
论文将测量个人收入分配差距的基尼系数方法引入到城镇居民消费差距的测定中。采用1992-2008年我国城镇居民各收入分组的消费数据,计算了食品、衣着、家庭设备用品及服务、医疗保健、交通通讯、文教娱乐、居住七类消费分项指标的差距及其对总消费差距的贡献,并通过反事实方法模拟分析分项指标对总体消费差异的影响。研究发现:第一,城镇居民消费差距与收入差距保持同步的发展趋势,但消费基尼系数一般小于同期收入基尼系数;第二,尽管恩格尔系数的持续下降一直成为平抑居民消费差距的最重要因素,但其对总体差距的贡献程度呈逐步弱化态势;第三,交通通讯和文教娱乐消费,尤其是前者,已逐步成为影响居民总体消费差距的重要力量;第四,虽然居民家庭设备消费差距一直高居不下,但是其对总体消费差距影响程度呈现出逐步弱化趋向。  相似文献   
55.
Quan-Ke Pan 《Omega》2012,40(2):166-180
Lot-streaming flow shops have important applications in different industries including textile, plastic, chemical, semiconductor and many others. This paper considers an n-job m-machine lot-streaming flow shop scheduling problem with sequence-dependent setup times under both the idling and no-idling production cases. The objective is to minimize the maximum completion time or makespan. To solve this important practical problem, a novel estimation of distribution algorithm (EDA) is proposed with a job permutation based representation. In the proposed EDA, an efficient initialization scheme based on the NEH heuristic is presented to construct an initial population with a certain level of quality and diversity. An estimation of a probabilistic model is constructed to direct the algorithm search towards good solutions by taking into account both job permutation and similar blocks of jobs. A simple but effective local search is added to enhance the intensification capability. A diversity controlling mechanism is applied to maintain the diversity of the population. In addition, a speed-up method is presented to reduce the computational effort needed for the local search technique and the NEH-based heuristics. A comparative evaluation is carried out with the best performing algorithms from the literature. The results show that the proposed EDA is very effective in comparison after comprehensive computational and statistical analyses.  相似文献   
56.
刘耀  倪涛 《中国管理科学》2009,17(1):107-112
随着经济的不断发展,开展同业税负研究测算的意义也愈显重要.传统行业税负计算方法没有考虑非正常样本对计算结果的影响,所得到的税负平均值往往低于行业税负的正常值.本文首次将C4.5数据挖掘算法引入到行业税负测算过程中,有效避免了传统测算方法中的不足,并结合税收领域知识对该算法进行了改进应用;通过对算法测算结果进行验证表明,利用该算法选出的企业样本代表了真实的行业税负水平,具有很高的可信度.  相似文献   
57.
区间数排序的可能度计算模型是学术界一直在不断探索的基础性问题之一。区间数刻画着事物属性特征的取值范围,以往学术界都假设在区间内的取值服从均匀分布。本文将均匀分布推广到一般分布,运用概率论的方法,构建了一个新的区间数排序的可能度计算模型,由此修正了以往关于两个区间数全等的定义,提出了区间数形等的概念,同时进一步修正了可能度的自反性条件和区间数的综合排序方法,并将理论应用于多属性决策问题,给出了基本的决策过程,通过实例决策问题的计算,呈现了新理论和新方法的可行性和合理性,具有很好的推广应用价值。  相似文献   
58.
This paper reviews Jacob Mincer's contributions to the analyses of earnings and the distribution of earnings through his pioneering focus on labor market experience or on-the-job training. It begins with a brief discussion of the theoretical literature on the distribution of earnings in the pre-Mincer period, and then discusses his analysis of human capital and earnings developed in his 1957 doctoral dissertation and 1958 Journal of Political Economy (JPE) article. Further analyses of on-the-job training, and in particular estimates of the rate of return from on-the-job training, are presented in his 1962 JPE paper. The synergy between Mincer and Becker during the 1960s is discussed, as is the development of the schooling-earnings function by Gary S. Becker and Barry R. Chiswick (1966). Jacob Mincer extended this relationship by incorporating experience to form the human capital earnings function in his Schooling, Experience and Earnings (1974). Subsequent modifications, extensions, tests of robustness and the wide applicability of the human capital earnings function are presented.  相似文献   
59.
In this paper we consider semiparametric inference methods for the time scale parameters in general time scale models (Oakes, 1995, Duchesne and Lawless, 2000). We use the results of Robins and Tsiatis (1992) and Lin and Ying (1995) to derive a rank-based estimator that is more efficient and robust than the traditional minimum coefficient of variation (min CV) estimator of Kordonsky and Gerstbakh (1993) for many underlying models. Moreover, our estimator can readily handle censored samples, which is not the case with the min CV method.  相似文献   
60.
We consider the competing-risks problem without making any assumption concerning the independence of the risks. Maximum-likelihood estimates of the cause-specific hazard rates are obtained under the condition that their ratio is monotone. We also consider the likelihood-ratio test for testing the proportionality of two cause-specific hazard rates against the alternative that the ratio of these two hazard rates is monotonic. This testing problem is equivalent to testing independence against likelihood-ratio dependence of the time to failure and the cause of failure in the competing-risks setup. We allow for random censoring on the right. The asymptotic null distribution of the test statistic is obtained and is found to be of the chi-bar-square type. The problem is extended to the case of more than two risks. A numerical example is given to illustrate the procedure.  相似文献   
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