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131.
The aim of this study was to develop a modified quantitative microbial risk assessment (QMRA) framework that could be applied as a decision support tool to choose between alternative drinking water interventions in the developing context. The impact of different household water treatment (HWT) interventions on the overall incidence of diarrheal disease and disability adjusted life years (DALYs) was estimated, without relying on source water pathogen concentration as the starting point for the analysis. A framework was developed and a software tool constructed and then implemented for an illustrative case study for Nepal based on published scientific data. Coagulation combined with free chlorine disinfection provided the greatest estimated health gains in the short term; however, when long‐term compliance was incorporated into the calculations, the preferred intervention was porous ceramic filtration. The model demonstrates how the QMRA framework can be used to integrate evidence from different studies to inform management decisions, and in particular to prioritize the next best intervention with respect to estimated reduction in diarrheal incidence. This study only considered HWT interventions; it is recognized that a systematic consideration of sanitation, recreation, and drinking water pathways is important for effective management of waterborne transmission of pathogens, and the approach could be expanded to consider the broader water‐related context.  相似文献   
132.
开放经济下对外直接投资(OFDI)已成为我国融入世界经济的主要途径,在优化产业结构、推进经济转型等方面扮演着重要角色。根据OFDI与产业结构升级及传导路径的互动机理分析,在对安徽省OFDI投资概况和产业结构现状进行分析的基础上,选取2003—2017年相关数据为样本构建VAR模型,运用ADF检验、脉冲响应函数等方法从产业结构总水平角度,实证分析得出短期内安徽省OFDI所能带来的产业结构升级效应并不显著的结论。进而从具体传导路径角度,采用主成分分析法,从10个变量中提取主成分构建VAR模型,运用脉冲响应等方法实证分析得出安徽省OFDI可通过贸易、省内投资、就业和技术路径来促进产业结构升级。为此,安徽省应扩大OFDI规模,提升OFDI质量和效益;增强企业竞争实力和科技创新能力,优化对外投资结构;发挥政府宏观调控和政策引导作用,加大对企业的扶持力度。  相似文献   
133.
The procedural justice model has become widely recognized as a key crime prevention and reduction strategy, spurring its adoption across police agencies throughout the United States in an effort to address mounting concerns regarding police use of force. Recent critiques, however, have called attention to the need for greater examination of potential contributing factors that are underdeveloped in investigations of the procedural justice model, including the role of emotions. This article takes stock of interdisciplinary advancements to critically examine scholarly investigations exploring associations between procedural (in)justice, emotions, and compliance behaviors within the context of police-citizen interactions. In doing so, continued gaps are identified. Lastly, this article concludes by identifying future pathways and recommendations for the scholarly advancement of our understanding of emotions and their continued relevance to the procedural justice model.  相似文献   
134.
以学界广为关注的“S(是)AV(())的”句式为例,重点分析“(是)……的”类句式在语境、词汇和句法三个层面所显示的不同已然义特征,并以此为基础对国内外关于已然义“(是)……的”类句式的相关研究进行简要的评价。  相似文献   
135.
Suburbs across the US are experiencing dramatic demographic shifts, yet there is little research available on how suburban school districts are dealing with these changes. In this article, we examine the discourses surrounding race and demographic change in three suburban school districts that have been undergoing rapid demographic changes and which contain demographically distinct areas within their district boundaries. Utilizing a critical discourse analysis (CDA) approach, we analyze how the policy context (federal and state) frames actors’ discourses and understandings of race, paying particular attention to the political and institutional factors affecting school policy. We illustrate how the discourse, in turn, is related to the actions (or inactions) taken by district and school leaders to respond to demographic change. We conclude the article by discussing policy implications and potential challenges districts may face in the future if efforts to purposively address racial changes continue to be avoided.  相似文献   
136.
A random effects model for analyzing mixed longitudinal count and ordinal data is presented where the count response is inflated in two points (k and l) and an (k,l)-Inflated Power series distribution is used as its distribution. A full likelihood-based approach is used to obtain maximum likelihood estimates of parameters of the model. For data with non-ignorable missing values models with probit model for missing mechanism are used.The dependence between longitudinal sequences of responses and inflation parameters are investigated using a random effects approach. Also, to investigate the correlation between mixed ordinal and count responses of each individuals at each time, a shared random effect is used. In order to assess the performance of the model, a simulation study is performed for a case that the count response has (k,l)-Inflated Binomial distribution. Performance comparisons of count-ordinal random effect model, Zero-Inflated ordinal random effects model and (k,l)-Inflated ordinal random effects model are also given. The model is applied to a real social data set from the first two waves of the national longitudinal study of adolescent to adult health (Add Health study). In this data set, the joint responses are the number of days in a month that each individual smoked as the count response and the general health condition of each individual as the ordinal response. For the count response there is incidence of excess values of 0 and 30.  相似文献   
137.
In this article, we lament the effects of practice-distant research and associated policy initiatives on contemporary children's services in England. In the last decade, as a result of high profile inquiries into non-accidental child deaths, statutory children's social care services in the UK have been subject to a wide-reaching ‘modernization’ programme. We studied decision-making in the high blame environment of local authority children's services. Our research sought to examine the relationship between performance management and the impact of anticipated blame within the decision-making practices of those providing, supervising and managing these services. We show that systems and technologies can be developed which both assist the users in their daily work and achieve desired organizational goals, but without an ethnographically informed, practice-near approach, unsafe work regimes and practices can ensue.  相似文献   
138.

In this article, the validity of procedures for testing the significance of the slope in quantitative linear models with one explanatory variable and first-order autoregressive [AR(1)] errors is analyzed in a Monte Carlo study conducted in the time domain. Two cases are considered for the regressor: fixed and trended versus random and AR(1). In addition to the classical t -test using the Ordinary Least Squares (OLS) estimator of the slope and its standard error, we consider seven t -tests with n-2\,\hbox{df} built on the Generalized Least Squares (GLS) estimator or an estimated GLS estimator, three variants of the classical t -test with different variances of the OLS estimator, two asymptotic tests built on the Maximum Likelihood (ML) estimator, the F -test for fixed effects based on the Restricted Maximum Likelihood (REML) estimator in the mixed-model approach, two t -tests with n - 2 df based on first differences (FD) and first-difference ratios (FDR), and four modified t -tests using various corrections of the number of degrees of freedom. The FDR t -test, the REML F -test and the modified t -test using Dutilleul's effective sample size are the most valid among the testing procedures that do not assume the complete knowledge of the covariance matrix of the errors. However, modified t -tests are not applicable and the FDR t -test suffers from a lack of power when the regressor is fixed and trended ( i.e. , FDR is the same as FD in this case when observations are equally spaced), whereas the REML algorithm fails to converge at small sample sizes. The classical t -test is valid when the regressor is fixed and trended and autocorrelation among errors is predominantly negative, and when the regressor is random and AR(1), like the errors, and autocorrelation is moderately negative or positive. We discuss the results graphically, in terms of the circularity condition defined in repeated measures ANOVA and of the effective sample size used in correlation analysis with autocorrelated sample data. An example with environmental data is presented.  相似文献   
139.
美学与审美学是两个存在差异的学术范畴,由于西语只有aesthetics一个术语,致使长期以来二者混淆在一起。为了厘清二者的边界,为美学的复兴开辟道路,为美学正名成为当务之急。学界通常所谓的aesthetics("美学")其实是"审美学","美学"应该另有其名。两百年来,美学家为"美学"创造了多个名字,其中以callology最为恰当。但是,真正最为恰切精当的"美学"一词是源自古希腊的philocaly(爱美之学)。  相似文献   
140.
Peto and Peto (1972) have studied rank invariant tests to compare two survival curves for right censored data. We apply their tests, including the logrank test and the generalized Wilcoxon test, to left truncated and interval censored data. The significance levels of the tests are approximated by Monte Carlo permutation tests. Simulation studies are conducted to show their size and power under different distributional differences. In particular, the logrank test works well under the Cox proportional hazards alternatives, as for the usual right censored data. The methods are illustrated by the analysis of the Massachusetts Health Care Panel Study dataset.  相似文献   
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