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1.
In this study, the E-Bayesian and hierarchical Bayesian of the scalar parameter of a Gompertz distribution under Type II censoring schemes were estimated based on fuzzy data under the squared error (SE) loss function and the efficiency of the proposed methods was compared with each other and with the Bayesian estimator using Monte Carlo simulation.  相似文献   
2.
Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study.  相似文献   
3.
It is well-known that, under Type II double censoring, the maximum likelihood (ML) estimators of the location and scale parameters, θ and δ, of a twoparameter exponential distribution are linear functions of the order statistics. In contrast, when θ is known, theML estimator of δ does not admit a closed form expression. It is shown, however, that theML estimator of the scale parameter exists and is unique. Moreover, it has good large-sample properties. In addition, sharp lower and upper bounds for this estimator are provided, which can serve as starting points for iterative interpolation methods such as regula falsi. Explicit expressions for the expected Fisher information and Cramér-Rao lower bound are also derived. In the Bayesian context, assuming an inverted gamma prior on δ, the uniqueness, boundedness and asymptotics of the highest posterior density estimator of δ can be deduced in a similar way. Finally, an illustrative example is included.  相似文献   
4.
Owing to the extreme quantiles involved, standard control charts are very sensitive to the effects of parameter estimation and non-normality. More general parametric charts have been devised to deal with the latter complication and corrections have been derived to compensate for the estimation step, both under normal and parametric models. The resulting procedures offer a satisfactory solution over a broad range of underlying distributions. However, situations do occur where even such a large model is inadequate and nothing remains but to consider non- parametric charts. In principle, these form ideal solutions, but the problem is that huge sample sizes are required for the estimation step. Otherwise the resulting stochastic error is so large that the chart is very unstable, a disadvantage that seems to outweigh the advantage of avoiding the model error from the parametric case. Here we analyse under what conditions non-parametric charts actually become feasible alternatives for their parametric counterparts. In particular, corrected versions are suggested for which a possible change point is reached at sample sizes that are markedly less huge (but still larger than the customary range). These corrections serve to control the behaviour during in-control (markedly wrong outcomes of the estimates only occur sufficiently rarely). The price for this protection will clearly be some loss of detection power during out-of-control. A change point comes in view as soon as this loss can be made sufficiently small.  相似文献   
5.
第二次世界大战以雅尔塔体系为基础形成了以美苏两大国为首的世界政治格局,对战后世界政治、经济和国际关系产生了深刻影响。随着两极格局的终结,世界又朝着多极化趋势发展。  相似文献   
6.
许刚雁 《阴山学刊》2007,20(1):81-84
德国在二战后被分裂成两个国家,就其外部因素来讲,是由于以美苏为首的大国合作政策在战后逐渐走向对抗并导致冷战的产物,是外部力量施加于德国的结果,而在走向对抗的过程中,美苏在德国赔偿问题上的冲突,是导致德国分裂的一个重要原因。  相似文献   
7.
Many new anticancer agents can be combined with existing drugs, as combining a number of drugs may be expected to have a better therapeutic effect than monotherapy owing to synergistic effects. Furthermore, to drive drug development and to reduce the associated cost, there has been a growing tendency to combine these as phase I/II trials. With respect to phase I/II oncology trials for the assessment of dose combinations, in the existing methodologies in which efficacy based on tumor response and safety based on toxicity are modeled as binary outcomes, it is not possible to enroll and treat the next cohort of patients unless the best overall response has been determined in the current cohort. Thus, the trial duration might be potentially extended to an unacceptable degree. In this study, we proposed a method that randomizes the next cohort of patients in the phase II part to the dose combination based on the estimated response rate using all the available observed data upon determination of the overall response in the current cohort. We compared the proposed method to the existing method using simulation studies. These demonstrated that the percentage of optimal dose combinations selected in the proposed method is not less than that in the existing method and that the trial duration in the proposed method is shortened compared to that in the existing method. The proposed method meets both ethical and financial requirements, and we believe it has the potential to contribute to expedite drug development.  相似文献   
8.
In recent years, seamless phase I/II clinical trials have drawn much attention, as they consider both toxicity and efficacy endpoints in finding an optimal dose (OD). Engaging an appropriate number of patients in a trial is a challenging task. This paper attempts a dynamic stopping rule to save resources in phase I/II trials. That is, the stopping rule aims to save patients from unnecessary toxic or subtherapeutic doses. We allow a trial to stop early when widths of the confidence intervals for the dose-response parameters become narrower or when the sample size is equal to a predefined size, whichever comes first. The simulation study of dose-response scenarios in various settings demonstrates that the proposed stopping rule can engage an appropriate number of patients. Therefore, we suggest its use in clinical trials.  相似文献   
9.
ABSTRACT

An estimated 230,000 Polish Jews escaped Nazi persecution during World War II by flight or deportation to the interior of the Soviet Union. This article examines early postwar Yiddish and Polish sources on their survival in Soviet exile such as poems, newspaper articles, and witness testimonies. Two sets of sources are analyzed in-depth, testimonies written by young people in Jewish Displaced Persons (DP) camps in occupied Germany and Yiddish poetry from Poland and the DP camps. The author argues that many former exiles were eager to write down their experiences. In doing so, they were aware of the complex nature of deportation and flight that characterized the experiences of Polish Jews in the Soviet Union. In their testimonies many young witnesses express their understanding that they too were “marked by the khurbn.” Whereas Yiddish poetry from the same period helps us understand how writers dealt with their own story of wartime survival outside the realm of German persecution. In their poetry they seek meaning in their own suffering and express their desire to establish a dialogue with other survivors.  相似文献   
10.
Much of public relations historiography on World War II focuses on the government uses of the function. This study fills a gap in the literature by exploring how a non-governmental organization called the American Social Hygiene Association (ASHA) used persuasion communication efforts to enlist the aid of management, labor, and local communities in the United States in the control of venereal disease (VD) rates. The case study advances a more diverse understanding of how activists have utilized public relations and found that the social reformers’ use of persuasive communications strategies and activities aligned with the view of public relations as the strategic and intentional participation in the social construction of meaning to achieve a planned outcome.  相似文献   
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