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   22786篇
  免费   641篇
  国内免费   1篇
财政金融   4722篇
工业经济   1798篇
计划管理   3853篇
经济学   5063篇
综合类   268篇
运输经济   106篇
旅游经济   314篇
贸易经济   3864篇
农业经济   1100篇
经济概况   2210篇
邮电经济   130篇
  2021年   155篇
  2020年   289篇
  2019年   389篇
  2018年   441篇
  2017年   521篇
  2016年   516篇
  2015年   372篇
  2014年   520篇
  2013年   2229篇
  2012年   662篇
  2011年   708篇
  2010年   625篇
  2009年   738篇
  2008年   639篇
  2007年   638篇
  2006年   586篇
  2005年   499篇
  2004年   463篇
  2003年   544篇
  2002年   492篇
  2001年   457篇
  2000年   483篇
  1999年   420篇
  1998年   442篇
  1997年   430篇
  1996年   402篇
  1995年   388篇
  1994年   391篇
  1993年   369篇
  1992年   413篇
  1991年   411篇
  1990年   339篇
  1989年   285篇
  1988年   302篇
  1987年   265篇
  1986年   318篇
  1985年   437篇
  1984年   410篇
  1983年   350篇
  1982年   384篇
  1981年   380篇
  1980年   331篇
  1979年   319篇
  1978年   297篇
  1977年   223篇
  1976年   220篇
  1975年   223篇
  1974年   160篇
  1973年   185篇
  1972年   145篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
We collected 469 frontal face images of Ukrainian cabinet ministers who were in office in 2000–2020. For each image, the minister's body mass index was estimated using a computer vision algorithm. The time series of median estimated body mass index of cabinet ministers co-moves over time with two existing measures of corruption – World Bank worldwide governance indicator Control of Corruption, and the discrepancy between the quantity of luxury wristwatches exported from Switzerland to Ukraine (reported by Swiss statistics) and the corresponding quantity imported by Ukraine from Switzerland (reported by Ukrainian statistics).  相似文献   
2.
We extend the entrepreneurship literature to include positive psychological capital — an individual or organization's level of psychological resources consisting of hope, optimism, resilience, and confidence — as a salient signal in crowdfunding. We draw from the costless signaling literature to argue that positive psychological capital language usage enhances crowdfunding performance. We examine 1726 crowdfunding campaigns from Kickstarter, finding that entrepreneurs conveying positive psychological capital experience superior fundraising performance. Human capital moderates this relationship while social capital does not, suggesting that costly signals may, at times, enhance the influence of costless signals. Post hoc analyses suggest findings generalize across crowdfunding types, but not to IPOs.  相似文献   
3.
This study investigates the correlates of a resident's walking behaviors and aims to shed light on mechanisms through which walking may be encouraged. The results of this investigation paint a complex and nuanced picture of the residents’ walking behaviors in South East Queensland, Australia. The results suggest that sociodemographic characteristics separately may contribute greatly to whether or not one engages in walking behaviors. Further, cumulatively these differences might be greater for some groups of residents compared to others. One of the most prominent findings of the study is that the purpose, the characteristics of the origin, and the characteristics of the destination of a trip tended to be similar in the heterogeneity they exhibit over the distribution of time spent walking. For example, pick something up, undertake work, or engage in personal business, move to or from a workplace, shop, or social place are activities that tend to be associated with walking as a main mode of transport and a higher number of walking episodes. However, these trips tended to be short.  相似文献   
4.
5.
6.
We model how firms releasing information on different dates causes the CAPM to fail, requiring an additional factor based on the information structure to price assets. We exemplify this mechanism’s empirical relevance using quarterly earnings announcements, which cluster across months along size and book-to-market. Seventy percent of the alpha reduction from including SMB and HML occurs in the four main earnings announcement months. The information structure factor accounts for all of SMB and HML’s seasonal alpha reduction and one third of their overall alpha reduction. Controlling for size and book-to-market, exposures to SMB and HML vary with firms’ earnings announcement month.  相似文献   
7.
The lack of a validated measure of active–passive union participation and a dearth of research into the relationship between generational cohort and union participation challenge union leaders to develop policies and practices to facilitate union renewal. We address these issues by (a) developing a multidimensional measure of union participation that captures both active and passive components, (b) using structural equation modelling to validate the measure within a nomological framework, and (c) investigating the impact of generational cohort on all paths in our framework. Data from members of a large American union confirm that generational cohort influences how union members participate in their union. The two‐factor measure developed in this study facilitates research into antecedents and outcomes of passive and active union participation. Our findings should also prove useful to unions seeking to increase participation within their membership, academics researching unions and generational cohort, and human resource practitioners operating in unionised environments.  相似文献   
8.
This paper studies the expansion of an option price (with bounded Lipschitz payoff) in a stochastic volatility model including a local volatility component. The stochastic volatility is a square root process, which is widely used for modeling the behavior of the variance process (Heston model). The local volatility part is of general form, requiring only appropriate growth and boundedness assumptions. We rigorously establish tight error estimates of our expansions, using Malliavin calculus. The error analysis, which requires a careful treatment because of the lack of weak differentiability of the model, is interesting on its own. Moreover, in the particular case of call–put options, we also provide expansions of the Black–Scholes implied volatility that allow to obtain very simple formulas that are fast to compute compared to the Monte Carlo approach and maintain a very competitive accuracy.  相似文献   
9.
We tested relationships between employee quit rates and two bundles of human resource (HR) practices that reflect the different interests of the two parties involved in the employment relationship. To understand the boundary conditions for these effects, we examined an external contingency proposed to influence the exchange-based effects of HR practices on subsequent quit rates – the local industry-specific unemployment rate – and an internal contingency proposed to shape employees’ conceptualization of their exchange relationship – their employment status (i.e. full-time, part-time and temporary employment). Analyses of lagged data from over 200 Canadian establishments show that inducement HR practices (e.g. extensive benefits) and performance expectation HR practices (e.g. performance-based bonuses) had different effects on quit rates, and the former effect was moderated by unemployment rate. The effects of HR practices on quit rates did not differ between FT and PT employees, but a different pattern of main and interactive effects was found among temporary workers. These findings suggest that employees’ exchange-based decisions to leave may be less affected by the number of hours they expect to work each week, and more by the number of weeks they expect to work.  相似文献   
10.
The present study investigates a potential preventive factor in relation to workplace bullying. Specifically, we examine how climate for conflict management (CCM) may be related to less bullying, increased work engagement, as well as whether CCM is a moderator in the bullying engagement relationship. The study was based on a cross-sectional survey among employees in a transport company (N = 312). Hypotheses were tested simultaneously in a moderated mediation analysis which showed that bullying and job engagement were related (H1), CCM was related to less reports of bullying (H2), CCM was related to work engagement (H3) and that CCM was indirectly related to job engagement through bullying (H4), but only when CCM was weak (H5). That is, CCM moderated the relationship between bullying and work engagement in that this relationship only existed when CCM was low. The present study contributes to theory within this research field by showing that organizational measures may not only prevent bullying, but may also affect how employees react when subjected to bullying. Furthermore, the effect of climate in relation to bullying may be down to the narrow bandwidth facet of CCM. The study informs employers how they may act to prevent bullying while also reducing the potential negative outcomes of those cases of bullying that inevitably will show up from time to time.  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