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1.
论新疆生产建设兵团的历史地位和作用   总被引:14,自引:0,他引:14  
该文通过对新疆生产建设兵团产生的历史背景及其对开发、建设和保卫新疆的巨大作用的历史回顾 ,阐述了兵团作为新疆经济建设、守卫边防和维护祖国领土完整、保证新疆社会稳定、促进民族团结的重要力量的历史地位及其历史必然性 ;从历史和现实两个方面揭示了屯垦戍边事业在开发建设边疆、稳定边疆、巩固国防中极其重要的战略地位。在改革开放的新时期和西部大开发中 ,兵团具有更加突出的地位 ,更应加快建设和发展 ,发挥更大的作用 ,为党和人民再作新的贡献  相似文献   
2.
文章以广东工业大学“九五”期间科技投入与产出的统计数据为基础,描述了学校的科研状况,在分析其不足的同时,认为可通过制定合理的科研发展目标和发展战略、积极发挥科研管理的职能、注重“产学研”结合、巩固和建设几个有较大影响的重点学科等对策来提高学校的科研水平。  相似文献   
3.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations.  相似文献   
4.
A common problem in environmental epidemiology is the estimation and mapping of spatial variation in disease risk. In this paper we analyse data from the Walsall District Health Authority, UK, concerning the spatial distributions of cancer cases compared with controls sampled from the population register. We formulate the risk estimation problem as a nonparametric binary regression problem and consider two different methods of estimation. The first uses a standard kernel method with a cross-validation criterion for choosing the associated bandwidth parameter. The second uses the framework of the generalized additive model (GAM) which has the advantage that it can allow for additional explanatory variables, but is computationally more demanding. For the Walsall data, we obtain similar results using either the kernel method with controls stratified by age and sex to match the age–sex distribution of the cases or the GAM method with random controls but incorporating age and sex as additional explanatory variables. For cancers of the lung or stomach, the analysis shows highly statistically significant spatial variation in risk. For the less common cancers of the pancreas, the spatial variation in risk is not statistically significant.  相似文献   
5.

Asymptotic confidence (delta) intervals and intervals based upon the use of Fieller's theorem are alternative methods for constructing intervals for the <$>\gamma<$>% effective doses (ED<$>_\gamma<$>). Sitter and Wu (1993) provided a comparison of the two approaches for the ED<$>_{50}<$>, for the case in which a logistic dose response curve is assumed. They showed that the Fieller intervals are generally superior. In this paper, we introduce two new families of intervals, both of which include the delta and Fieller intervals as special cases. In addition we consider interval estimation of the ED<$>_{90}<$> as well as the ED<$>_{50}<$>. We provide a comparison of the various methods for the problem of constructing a confidence interval for the ED<$>_\gamma<$>.  相似文献   
6.
Probabilistic risk assessment (PRA) is a useful tool to assess complex interconnected systems. This article leverages the capabilities of PRA tools developed for industrial and nuclear risk analysis in community resilience evaluations by modeling the food security of a community in terms of its built environment as an integrated system. To this end, we model the performance of Gilroy, CA, a moderate‐size town, with regard to disruptions in its food supply caused by a severe earthquake. The food retailers of Gilroy, along with the electrical power network, water network elements, and bridges are considered as components of a system. Fault and event trees are constructed to model the requirements for continuous food supply to community residents and are analyzed efficiently using binary decision diagrams (BDDs). The study also identifies shortcomings in approximate classical system analysis methods in assessing community resilience. Importance factors are utilized to rank the importance of various factors to the overall risk of food insecurity. Finally, the study considers the impact of various sources of uncertainties in the hazard modeling and performance of infrastructure on food security measures. The methodology can be applicable for any existing critical infrastructure system and has potential extensions to other hazards.  相似文献   
7.
利用189个国家和地区1995—2011年的数据实证检验公共卫生支出规模对一个国家的健康结果(婴儿死亡率和出生时的平均期望寿命)的影响,结果表明,公共卫生支出占GDP的比重对婴儿死亡率和出生时的平均期望寿命的影响具有门槛效应,门槛值分别位于1.9%和6.62%。分段回归结果显示,公共卫生支出占GDP的比重低于1.9%时,公共卫生投入对出生时的平均期望寿命没有显著影响,对婴儿死亡率的影响较弱;超过1.9%后,公共卫生投入的规模效应开始体现,对健康结果指标的影响均显著增强;超过6.62%后,公共卫生投入对婴儿死亡率的影响不再显著,对出生时平均期望寿命的弹性系数不再变化,单位边际贡献不再增加。中国当前政府卫生投入规模仍然较低,需要继续增大公共资金投入、降低个人卫生支出比重。  相似文献   
8.
Abstract

The relationship of the five-factor model of personality to working alliance, symptoms and well-being was examined in a diverse community mental health sample (N = 103). Agreeableness, openness, extraversion and conscientiousness were associated with alliance. Neuroticism was strongly associated with symptoms, and negatively associated with well-being. Extraversion was moderately associated with well-being. Personality is deserving of further study as a potentially important influence on therapy process and outcome. Part of the much-replicated association of alliance with outcome may be accounted for by personality. Implications for social work practice and research are discussed.  相似文献   
9.
文章从生命周期的角度入手,以期为理解收入不平等提供一个不同的视角.基尼系数本质上衡量的是结果的不平等,收入所得税等政府政策也侧重对结果不平等的调整,但收入结果的不平等起源于机会的不平等,强化于过程的不平等,最终才表现为结果的不平等.机会不平等、过程不平等和结果不平等对应不同的生命周期阶段,需要不同的政策措施.对于机会不平等,政府应着眼于消除户籍制度等对不同人群的制度性歧视,减少我国区域发展水平的差距;推动幼儿和青少年教育与医疗服务的均等化,为他们创造一个公平的养教环境.对于过程不平等,一个重要的方面是建立对各种所有制员工和不同雇佣关系职工都公平的城乡统一的市场环境,消除劳动力市场中同工不同酬等歧视现象,尤其是取消国家制度和政策造成的劳动力市场分割.对于结果不平等,要兼顾公平和效率,在现有个人所得税、最低生活保障制度等基础上,逐步建立城乡统一、公平公正的收入调节和社会保障体系.  相似文献   
10.
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   
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