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   278篇
  免费   8篇
管理学   55篇
民族学   3篇
人口学   49篇
理论方法论   10篇
综合类   14篇
社会学   70篇
统计学   85篇
  2023年   3篇
  2022年   3篇
  2021年   7篇
  2020年   10篇
  2019年   15篇
  2018年   25篇
  2017年   26篇
  2016年   13篇
  2015年   12篇
  2014年   11篇
  2013年   30篇
  2012年   22篇
  2011年   8篇
  2010年   13篇
  2009年   12篇
  2008年   9篇
  2007年   10篇
  2006年   5篇
  2005年   8篇
  2004年   13篇
  2003年   6篇
  2002年   4篇
  2001年   6篇
  2000年   2篇
  1998年   2篇
  1996年   2篇
  1995年   4篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
  1988年   1篇
  1972年   1篇
排序方式: 共有286条查询结果,搜索用时 318 毫秒
141.
142.

We exploit a multistate generalisation of a classical, one‐sex, stable population model to evaluate structural and long‐term effects of changes in the attainment of adulthood. The demographic framework that inspired this paper is provided by Italy, where a strong delay in the transition to adulthood and union formation has been observed over the last several decades. Italy has also experienced very low fertility levels, and the subsequent ageing problems have become of primary concern. We first discuss a theoretical framework based on the model developed by Inaba (1995) and then include the process of transition to adulthood. We consider explicitly some specifications of the general model, and we present two distinct empirical applications, one using macrosimulation and the other one using a linear approximation. Our principal aim is to evaluate the impact of the delay in the attainment of adulthood on reproduction and on the age structure of the population.  相似文献   
143.
The situational theory of publics demonstrates that stakeholders are best segmented into active publics, given their high problem recognition, low constraint recognition, and high level of involvement in an issue. This study further demonstrates that low identification with an issue is significant as the public's situational drivers are increased by a high ethnocentric bias. This argument is investigated with regard to a specific type of public: journalists. The results confirmed previous discussions of how a specific public's situational behavior might be influenced by a referent criterion representing a biased mindset of that public toward the topic.  相似文献   
144.
Using a simple empirical approach, we analyze world and regional‐level cohort replacement as determined by the key components of population dynamics, i.e. fertility, survival, and migration, for 1950–2010, using UN data. We define two kinds of homeostatic relationships among these components: fertility responses to mortality change (type I) and migration responses to changes in net reproduction (type II), and show that both can be observed to some degree in this period. We examine the extent of cohort replacement embodied in the medium‐variant UN population projections over 2010–2100 and consider how the international migration assumptions made in such projections would be affected by a homeostatic perspective.  相似文献   
145.
The paper focuses on the Overall Equipment Effectiveness (OEE), a performance indicator that is extensively used in the industry. The aim is to extend the capabilities of the OEE, so as to capture the day-to-day fluctuations to which manufacturing performances are subjected. To this aim, manufacturing losses are decomposed into elementary causes and modelled as LR fuzzy numbers. Next, in order to compute the Fuzzy Overall Equipment Effectiveness (FOEE), single losses are aggregated using the ‘fuzzy transformation model’. This approach limits the fuzzy overestimation phenomenon and assures both results’ accuracy and robustness. An industrial application, part of a lean project carried on by an important Italian manufacturing firm, is finally presented. Results are encouraging, since the FOEE made it possible to trace back the share of the overall fluctuations that is ascribable to each cause of loss. In this way, it provided the basis for setting improvement priorities and directed the lean team toward the selection of appropriate corrective actions.  相似文献   
146.
We employ a novel data set to estimate a structural econometric model of the decisions under risk of players in a game show where lotteries present payoffs in excess of half a million dollars. The decisions under risk of players in the presence of large payoffs allow us to estimate the parameters of the curvature of the von Neumann–Morgenstern utility function—not only locally, as in previous studies in the literature, but also globally. Our estimates of relative risk aversion indicate that a constant relative risk aversion parameter of about 1 captures the average of the sample population. We also find that individuals are practically risk neutral at small stakes and risk averse at large stakes—a necessary condition, according to Rabin’s calibration theorem, for expected utility to provide a unified account of individuals’ attitudes toward risk. Finally, we show that for lotteries characterized by substantial stakes, nonexpected utility theories fit the data equally as well as expected utility theory.  相似文献   
147.
The aim of this article is to illustrate a procedure for applying the precautionary principle within a strategy for reducing the possibility of underestimating the effective risk caused by a phenomenon, product, or process, and of adopting insufficient risk reduction measures or overlooking their need. We start by simply defining risk as the product between the numerical expression of the adverse consequences of an event and the likelihood of its occurrence or the likelihood that such consequences will occur. Uncertainty in likelihood estimates and several key concepts inherent to the precautionary principle, such as sufficient certainty, prevention, and desired level of protection, are represented as fuzzy sets. The strategy described may be viewed as a simplified example of a precautionary decision process that has been chiefly conceived as a theoretical contribution to the debate concerning the precautionary principle, the quantification of its application, and the formal approach to such problems.  相似文献   
148.
In this paper we discuss and apply machine learning techniques, using ideas from a core research area in the artificial intelligence literature to analyse simultaneously timing, sequencing, and quantum of life course events from a comparative perspective. We outline the need for techniques which allow the adoption of a holistic approach to life course analysis, illustrating the specific case of the transition to adulthood. We briefly introduce machine learning algorithms to build decision trees and rule sets and then apply such algorithms to delineate the key features which distinguish Austrian and Italian pathways to adulthood, using Fertility and Family Survey data. The key role of sequencing and synchronization between events emerges clearly from the analysis. Billari F.C., Fürnkranz J., et Prskawetz A., 2006. Calendrier, séquence et intensitédes événements du cycle de vie : une application des techniques d’apprentissage par machine. Revue Européenne de Démographie, 22: 37–65  相似文献   
149.
Is African politics characterized by concentrated power in the hands of a narrow group (ethnically determined) that then fluctuates from one extreme to another via frequent coups? Employing data on the ethnicity of cabinet ministers since independence, we show that African ruling coalitions are surprisingly large and that political power is allocated proportionally to population shares across ethnic groups. This holds true even restricting the analysis to the subsample of the most powerful ministerial posts. We argue that the likelihood of revolutions from outsiders and coup threats from insiders are major forces explaining allocations within these regimes. Alternative allocation mechanisms are explored. Counterfactual experiments that shed light on the role of Western policies in affecting African national coalitions and leadership group premia are performed.  相似文献   
150.
I investigate how contractual hours and overtime premiums affect the decision either to moonlight or to work overtime. By reducing the standard workweek, the government or labor unions can affect the likelihood that a worker faces an hour constraint. An underemployed worker can secure additional earnings by working either on a second job or overtime. I model this decision as a bivariate probit. To create variation in the overtime rates, data for nine OECD countries are pooled. I find that decreasing the standard hours of work increases the probability of moonlighting. The overtime premium has an ambiguous effect on the probability of moonlighting, but it has a negative effect on the probability of working overtime. I thank R.L. Oaxaca, R. Stratton, and M. Nelson for their valuable comments and help. Any errors are solely my responsibility.  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