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   5214篇
  免费   131篇
  国内免费   1篇
财政金融   903篇
工业经济   360篇
计划管理   808篇
经济学   1121篇
综合类   67篇
运输经济   30篇
旅游经济   64篇
贸易经济   797篇
农业经济   238篇
经济概况   955篇
邮电经济   3篇
  2023年   32篇
  2020年   68篇
  2019年   107篇
  2018年   128篇
  2017年   132篇
  2016年   126篇
  2015年   69篇
  2014年   128篇
  2013年   506篇
  2012年   157篇
  2011年   194篇
  2010年   160篇
  2009年   151篇
  2008年   148篇
  2007年   138篇
  2006年   117篇
  2005年   92篇
  2004年   96篇
  2003年   92篇
  2002年   87篇
  2001年   117篇
  2000年   108篇
  1999年   85篇
  1998年   102篇
  1997年   77篇
  1996年   73篇
  1995年   92篇
  1994年   57篇
  1993年   84篇
  1992年   76篇
  1991年   80篇
  1990年   74篇
  1989年   78篇
  1988年   66篇
  1987年   73篇
  1986年   77篇
  1985年   83篇
  1984年   90篇
  1983年   64篇
  1982年   73篇
  1981年   66篇
  1980年   78篇
  1979年   66篇
  1978年   47篇
  1977年   50篇
  1976年   39篇
  1975年   49篇
  1974年   34篇
  1973年   39篇
  1972年   33篇
排序方式: 共有5346条查询结果,搜索用时 46 毫秒
941.
This paper examines the effect of network properties on the performance R&D joint projects. In particular, we examine the impact of network cohesion, diversity and shape on the performance of these of exploration and exploitation R&D projects. We test these measures using data on projects from European R&D networks developed under the framework of Eureka projects. The empirical results indicated some network properties enhance the project’s performance and these differ depending on the kind of technological project developed. Our results suggest a lower heterogeneity, greater cohesion and network centralisation in exploitation than in exploration projects. Our findings show different types of structures depending on the aim of the joint project and that there exist different degrees of cohesion between the partners that comprise the core and the peripheral nodes.  相似文献   
942.
The distribution of shocks to GDP growth rates is found to be exponential rather than normal. Their standard deviation scales with GDPβ where β=−0.15±0.03. These macroeconomic results place restrictions on the microeconomic structure of interactions between agents.  相似文献   
943.
We consider the class of law invariant convex risk measures with robust representation rh,p(X)=supfò01 [AV@Rs(X)f(s)-fp(s)h(s)] ds\rho_{h,p}(X)=\sup_{f}\int_{0}^{1} [AV@R_{s}(X)f(s)-f^{p}(s)h(s)]\,ds, where 1≤p<∞ and h is a positive and strictly decreasing function. The supremum is taken over the set of all Radon–Nikodym derivatives corresponding to the set of all probability measures on (0,1] which are absolutely continuous with respect to Lebesgue measure. We provide necessary and sufficient conditions for the position X such that ρ h,p (X) is real-valued and the supremum is attained. Using variational methods, an explicit formula for the maximizer is given. We exhibit two examples of such risk measures and compare them to the average value at risk.  相似文献   
944.
This paper is concerned with the comparison of seven estimators of the mean of the selected population from two normal populations with unknown means and common known variance under an asymmetric loss namely the LINEX loss function. The proposed estimators are invariant under location transformation. The bias and risks of the seven estimators are computed and compared. The conclusion recommend the use of δP (σ) which is simple to use and it is minimax. Received: January 1999  相似文献   
945.
A model of Australian wheat grower supply response was specified under the constrainsts of price and yield uncertainty, risk aversion, partial adjustment, and quadratic costs. The model was solved to obtain area planted. The results of estimation indicate that risk arising from prices and climate have had a significant influence on producer decision making. The coefficient of relative risk aversion and short‐run and long‐run elasticities of supply with respect to price were calculated. Wheat growers' risk premium, expected at the start of the season for exposed price and yield risk, was 2.8 percent of revenue or 10.4 percent of profit as measured by producer surplus. © 2000 John Wiley & Sons, Inc. Jrl Fut Mark 20: 345–359, 2000.  相似文献   
946.
This study extends previous research on organizational adaptation to major environmental shifts by empirically examining the potential constraining effects of organizational form, operationalized using the Miles and Snow typology, on the type of responses enacted as well as the performance effects of the responses. Results indicate that a fit between environmental contingencies and organizational form relates to superior performance. The results also provide support for the idea that organizations systematically move toward the higher‐performing forms for a given environment. Consistent with organizational configuration logic, while these responses lead to performance improvements when a between‐form change is made, they do not necessarily lead to performance improvements when a within‐form change is made. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
947.
Studies of the predictive ability of the Federal Reserve's Beige Book for aggregate output and employment have proven inconclusive. This might be attributed, in part, to its irregular release schedule. We use a model that allows for data sampling at mixed frequencies to analyze the predictive power of the Beige Book. We find that the Beige Book's national summary and District reports predict GDP and aggregate employment and that most District reports provide information content for regional employment. In addition, there appears to be an asymmetry in the predictive content of the Beige Book language.  相似文献   
948.
Short horizons, time inconsistency, and optimal social security   总被引:1,自引:0,他引:1  
We study the optimal provision of social security in a dynamically efficient economy using a continuous-time overlapping-generations model in which consumers have short planning horizons. The short-horizon mechanism leads to dynamic optimization that is time-inconsistent over the life cycle. Our calibrated general-equilibrium results are generally supportive of social security for a wide array of social welfare functions. Thus, the basic life-cycle model can be augmented with only this slight twist in order to rationalize a social security program with the current U.S. tax rate.  相似文献   
949.
Accounting scandals and concerns about the quality of financial statements have led to many calls for improved audit committee effectiveness. Prior research indicates that audit committee independence is positively related to effective oversight of the financial reporting process. Unfortunately, prior research has not provided an answer as to how much independence on the audit committee is enough. This is an important unanswered question because while Section 301 of the Sarbanes-Oxley Act of 2002 (SOX) currently requires all listed companies to maintain an audit committee that is 100% independent there has been much debate regarding easing the SOX requirements for smaller and foreign companies. In this paper we examine whether the regulatory requirements of a completely independent audit committee are necessary to obtain the monitoring benefits related to audit committee independence that have been documented in prior literature. Our results suggest that the benefits of audit committee independence are consistently achieved only when the audit committee is completely independent. These results provide support for the SOX requirement of 100% independent audit committees.  相似文献   
950.
Testing the CAPM revisited   总被引:1,自引:0,他引:1  
This paper re-examines the tests of the Sharpe–Lintner Capital Asset Pricing Model (CAPM). The null that the CAPM intercepts are zero is tested for ten size-based stock portfolios and for twenty five book-to-market sorted portfolios using five-year, ten-year and longer sub-periods during 1965–2004. The paper shows that the evidence for rejecting the CAPM on statistical grounds is weaker than the consensus view suggests, and highlights the pitfalls of testing multiple hypotheses with the conventional heteroskedasticity and autocorrelation robust (HAR) test with asymptotic P-values. The conventional test rejects the null for almost all sub-periods, which is consistent with the evidence in the literature. By contrast, the null is not rejected for most of the sub-periods by the new HAR tests developed by Kiefer et al. (2000), Kiefer and Vogelsang (2005), and Sun et al. (2008).  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