首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2623篇
  免费   162篇
  国内免费   3篇
管理学   259篇
劳动科学   1篇
民族学   40篇
人口学   283篇
丛书文集   59篇
理论方法论   213篇
综合类   177篇
社会学   1236篇
统计学   520篇
  2024年   3篇
  2023年   37篇
  2022年   34篇
  2021年   45篇
  2020年   112篇
  2019年   103篇
  2018年   205篇
  2017年   238篇
  2016年   182篇
  2015年   112篇
  2014年   135篇
  2013年   453篇
  2012年   217篇
  2011年   123篇
  2010年   109篇
  2009年   85篇
  2008年   82篇
  2007年   71篇
  2006年   68篇
  2005年   65篇
  2004年   38篇
  2003年   44篇
  2002年   37篇
  2001年   28篇
  2000年   20篇
  1999年   19篇
  1998年   8篇
  1997年   13篇
  1996年   9篇
  1995年   7篇
  1994年   9篇
  1993年   5篇
  1992年   7篇
  1991年   7篇
  1990年   8篇
  1989年   8篇
  1988年   8篇
  1987年   4篇
  1986年   5篇
  1985年   4篇
  1984年   2篇
  1979年   2篇
  1978年   2篇
  1977年   2篇
  1975年   2篇
  1974年   1篇
  1973年   3篇
  1972年   1篇
  1971年   2篇
  1967年   1篇
排序方式: 共有2788条查询结果,搜索用时 15 毫秒
1.
A conformance proportion is an important and useful index to assess industrial quality improvement. Statistical confidence limits for a conformance proportion are usually required not only to perform statistical significance tests, but also to provide useful information for determining practical significance. In this article, we propose approaches for constructing statistical confidence limits for a conformance proportion of multiple quality characteristics. Under the assumption that the variables of interest are distributed with a multivariate normal distribution, we develop an approach based on the concept of a fiducial generalized pivotal quantity (FGPQ). Without any distribution assumption on the variables, we apply some confidence interval construction methods for the conformance proportion by treating it as the probability of a success in a binomial distribution. The performance of the proposed methods is evaluated through detailed simulation studies. The results reveal that the simulated coverage probability (cp) for the FGPQ-based method is generally larger than the claimed value. On the other hand, one of the binomial distribution-based methods, that is, the standard method suggested in classical textbooks, appears to have smaller simulated cps than the nominal level. Two alternatives to the standard method are found to maintain their simulated cps sufficiently close to the claimed level, and hence their performances are judged to be satisfactory. In addition, three examples are given to illustrate the application of the proposed methods.  相似文献   
2.
Generally, the semiclosed-form option pricing formula for complex financial models depends on unobservable factors such as stochastic volatility and jump intensity. A popular practice is to use an estimate of these latent factors to compute the option price. However, in many situations this plug-and-play approximation does not yield the appropriate price. This article examines this bias and quantifies its impacts. We decompose the bias into terms that are related to the bias on the unobservable factors and to the precision of their point estimators. The approximated price is found to be highly biased when only the history of the stock price is used to recover the latent states. This bias is corrected when option prices are added to the sample used to recover the states' best estimate. We also show numerically that such a bias is propagated on calibrated parameters, leading to erroneous values. The Canadian Journal of Statistics 48: 8–35; 2020 © 2019 Statistical Society of Canada  相似文献   
3.
Explicitly aimed at understanding and controlling molecular and cellular processes at the root of senescence and biological aging, regenerative medicine aspires to artificially reproduce the biological processes that enable the body to regenerate itself. This no longer involves conserving the body's state of balance by combating disease, as in clinical medicine, but rather fighting degeneration itself. From stem cell research to gene therapy to the production of replacement tissues, regenerative medicine perfectly corresponds to the logic of biomedicalization specific to postmodern society. Based on a series of 18 interviews conducted with Canadian researchers and clinicians in the field of regenerative medicine, this article seeks to understand representations of the aging body among researchers in this field. Seen from a strictly negative angle, aging is assimilated by researchers to an inevitable catastrophe that nevertheless must be combated. More closely observing the theoretical model of regenerative biology and the types of treatments developed, it can be observed, however, that this medicine of the future does not target the elderly, but rather promises youth the ability to regenerate themselves to avoid aging.  相似文献   
4.
The conditional tail expectation (CTE) is an indicator of tail behavior that takes into account both the frequency and magnitude of a tail event. However, the asymptotic normality of its empirical estimator requires that the underlying distribution possess a finite variance; this can be a strong restriction in actuarial and financial applications. A valuable alternative is the median shortfall (MS), although it only gives information about the frequency of a tail event. We construct a class of tail Lp-medians encompassing the MS and CTE. For p in (1,2), a tail Lp-median depends on both the frequency and magnitude of tail events, and its empirical estimator is, within the range of the data, asymptotically normal under a condition weaker than a finite variance. We extrapolate this estimator and another technique to extreme levels using the heavy-tailed framework. The estimators are showcased on a simulation study and on real fire insurance data.  相似文献   
5.
The sociocultural content of foreign language textbooks has become a concern of scholars and practitioners owing to the fact that the traditional emphasis on purely linguistic issues has been expanded to embrace a language in context approach. This paper studies the English‐speaking communities that are described in English language teaching textbooks marketed in Spain. It examines to what extent an international and/or intercultural approach is a constituent element in their design.  相似文献   
6.
台湾地区人多地少,人地关系紧张,特别是自上世纪60年代以来,其经济获得了高速发展,土地供需矛盾更加突出.为此,台湾政府非常重视土地利用规划的作用,将其视为在市场失灵时政府干预土地资源配置的主要手段.经过几十年的发展,台湾土地利用规划已形成一套完整的体系,并在保护地区资源、支撑经济发展方面起到了重要作用.我国大陆土地利用规划起步较晚,许多方面有待完善,因此,认真研究台湾土地利用规划体系、内容及特点无疑会对我国大陆土地利用规划有积极的借鉴意义.  相似文献   
7.
Conservation biology aims at assessing the status of a population, based on information which is often incomplete. Integrated population modelling based on state‐space models appears to be a powerful and relevant way of combining into a single likelihood several types of information such as capture‐recapture data and population surveys. In this paper, the authors describe the principles of integrated population modelling and they evaluate its performance for conservation biology based on a case study, that of the black‐footed albatross, a northern Pacific albatross species suspected to be impacted by longline fishing  相似文献   
8.
This study investigated the relationship between the level of arousal (Heart Rate) and the number of erroneous perceptions among video poker players. Twelve regular and twelve occasional gamblers participated in a gambling session conducted in a natural environment. It was hypothesised that 1) a significant positive correlation would be observed between arousal and the number of erroneous verbalizations, 2) regular players would show a higher level of arousal than occasional players, and 3) they would emit more erroneous verbalizations. Results showed that hypotheses one and three were confirmed. Theoretical and practical implications of these results for the psychology of gambling are discussed.This study was supported by a grant from Loto-Québec.  相似文献   
9.
比较电视研究方法主要对不同国别不同语种的电视节目进行比较,从而发现和总结各民族与国家电视的价值和特色.比较电视分为影响比较和平行比较两种研究方法.影响比较侧重于影响者和被影响者的研究,平行研究侧重电视文本类同和对比的研究.把握好比较电视研究方法对于丰富和完善人们对于世界与人类电视的发展具有重要意义.  相似文献   
10.
中国就业市场中的性别歧视——对公众认知率的研究   总被引:1,自引:0,他引:1  
调查结果表明:女性更关注工作过程中的性别歧视和职业隔离的性别歧视现象,女性仅对应聘过程中的性别歧视现象如女性的相貌、身高等要求、外来打工妹的应聘两个问题的认知率高于男性;女性对性骚扰性别歧视认知率与男性没有显著差异;公众对各种性别歧视现象的总体认知水平不高.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号