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81.
本文给出了在有错检验情况下标准型抽样方案的设计方法,讨论了误检概率p,p′对抽样方案的影响,并给出抽样方案的实际应用。  相似文献   
82.
语篇的衔接与连贯问题   总被引:2,自引:0,他引:2  
语篇源自语言交际,是高于句子的层面,表示一个整体意义;语篇的衔接与连贯,分属两个概念,应该区别对待。语篇对于连贯的依赖似乎更为明显:衔接方式得当但语义不贯通的话语不是合格的语篇,衔接方式不明显但语义贯通的话语是合格的语篇;立足于语篇的基础理论,有利于我们提高对衔接与连贯的理性思考,可有效地防止在语篇分析过程中出现较大的偏误。  相似文献   
83.
处置效应是一种比较典型的投资者非理性行为。本文在线性量价回归模型的基础上,引入Grinblatt和Han[1]提出的资本利得突出量来检验中国股票投资者整体上是否存在处置效应。然后,使用新提出的6个参考价格与以往对股票市场研究中主要使用的两个参考价格(股票过去260周内加权平均价和过去52周内最高价)相比较,寻找更加适合处置效应研究的参考价格;同时,在选择不同的参考价格下,进一步检验投资者是否存在处置效应。研究结果表明:中国股票投资者整体上存在处置效应;并且在处置效应的研究中,新提出的参考价格——股票5周加权移动平均价明显优于以往学者提出的参考价格。因此,研究整个股票市场中投资者的处置效应时,使用该价格作为参考价格更加合理。  相似文献   
84.
刘小瑜 《统计教育》2008,(11):32-36
对收购活动的动机存在不同的看法,最终而言,每一项并购活动都是为了实现并购的协同价值。不同支付方式又与协同价值的分配和实现有着密切的联系。本文研究表明,在用现金进行支付的情况下,并购方股东既要承担协同价值未实现的全部损失,也能享有协同价值超额实现的全部收益。在发行固定数量股份的交易方式和发行固定价值股份的交易方式下,并购完成后市场对并购进行重新估价的结果,主要表现为买方公司股价的变动也会影响双方的利益。如果是股价上升,那么并购双方都将获益,而且往往对买方公司更为有利;如果股价下跌,那么买方公司也将承担更大的损失。这些结论为支付方式的选择和协同价值的实现提供了依据。  相似文献   
85.
在社会主义建设的探索中,没有搞清什么是社会主义和怎样建设社会主义是毛泽东发生失误的根本原因;民主集中制的破坏是毛泽东发生失误的重要原因;对国际、国内政治局势判断失误是其探索发生失误的直接原因.  相似文献   
86.
提出了一种按温度比例因子设计低温双极晶体管的设计规则。在考虑双极晶体管低温效应的前提下,着重分析了双极晶体管发射区和基区的浓度及宽度在低温下的变化情况。结合按温度比例子变化后任何特定温度下的双极晶体管电流增益和截止频率的优化结果,给出了这些参数在按温度比例因子规则设计时温度比例因子的变化参数。  相似文献   
87.
Predictive distributions are developed and illustrated for prediction in some Poisson errors in variables models. Two different situations in which multiplicative treatment effects are appropriate are considered within the context of predicting counts of road accidents. Hierarchical prior structures are investigated, and numerical integration and Gibbs sampling routines are used to derive the predictive and posterior probabilities. Examples of analyses are provided with data from road accidents in Sweden.  相似文献   
88.
One of the main aims of early phase clinical trials is to identify a safe dose with an indication of therapeutic benefit to administer to subjects in further studies. Ideally therefore, dose‐limiting events (DLEs) and responses indicative of efficacy should be considered in the dose‐escalation procedure. Several methods have been suggested for incorporating both DLEs and efficacy responses in early phase dose‐escalation trials. In this paper, we describe and evaluate a Bayesian adaptive approach based on one binary response (occurrence of a DLE) and one continuous response (a measure of potential efficacy) per subject. A logistic regression and a linear log‐log relationship are used respectively to model the binary DLEs and the continuous efficacy responses. A gain function concerning both the DLEs and efficacy responses is used to determine the dose to administer to the next cohort of subjects. Stopping rules are proposed to enable efficient decision making. Simulation results shows that our approach performs better than taking account of DLE responses alone. To assess the robustness of the approach, scenarios where the efficacy responses of subjects are generated from an E max model, but modelled by the linear log–log model are also considered. This evaluation shows that the simpler log–log model leads to robust recommendations even under this model showing that it is a useful approximation to the difficulty in estimating E max model. Additionally, we find comparable performance to alternative approaches using efficacy and safety for dose‐finding. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
89.
BackgroundExcessive weight gain during pregnancy can have adverse health outcomes for mother and infant throughout pregnancy. However, few studies have identified the psychosocial factors that contribute to women gaining excessive weight during pregnancy.AimTo review the existing literature that explores the impact of psychosocial risk factors (psychological distress, body image dissatisfaction, social support, self-efficacy and self-esteem) on excessive gestational weight gain.MethodsA systematic review of peer-reviewed English articles using Academic Search Complete, Cumulative Index to Nursing and Allied Health Literature, MEDLINE Complete, PsycINFO, Informit, Web of Science, and Scopus was conducted. Quantitative studies that investigated psychosocial factors of excessive GWG, published between 2000 and 2014 were included. Studies investigating mothers with a low risk of mental health issues and normally-developing foetuses were eligible for inclusion. From the total of 474 articles located, 12 articles were identified as relevant and were subsequently reviewed in full.FindingsSignificant associations were found between depression, body image dissatisfaction, and social support with excessive gestational weight gain. No significant relationships were reported between anxiety, stress, self-efficacy, or self-esteem and excessive gestational weight gain.ConclusionThe relationship between psychosocial factors and weight gain in pregnancy is complex; however depression, body dissatisfaction and social support appear to have a direct relationship with excessive gestational weight gain. Further research is needed to identify how screening for, and responding to, psychosocial risk factors for excessive gestational weight gain can be successfully incorporated into current antenatal care.  相似文献   
90.
We derive an exact F-test for random effects in the nested-error regression model. The derivation utilizes a matrix decomposition that offers a transformation of the response vector into two independent subvectors. When the random effects are absent, the test statistic reduces to a ratio of two independent residual sums of squares that are computed by fitting a regression model using each subvector. A small simulation study compares the power of the F-test with various recent tests and shows that the proposed test has a competitive performance under small as well as large number of clusters.  相似文献   
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