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   33784篇
  免费   387篇
财政金融   5920篇
工业经济   2186篇
计划管理   5406篇
经济学   7464篇
综合类   648篇
运输经济   134篇
旅游经济   307篇
贸易经济   7117篇
农业经济   769篇
经济概况   3600篇
信息产业经济   45篇
邮电经济   575篇
  2021年   127篇
  2020年   212篇
  2019年   275篇
  2018年   2601篇
  2017年   2346篇
  2016年   1524篇
  2015年   327篇
  2014年   464篇
  2013年   1896篇
  2012年   937篇
  2011年   2388篇
  2010年   2266篇
  2009年   2031篇
  2008年   1961篇
  2007年   2235篇
  2006年   480篇
  2005年   722篇
  2004年   808篇
  2003年   888篇
  2002年   597篇
  2001年   393篇
  2000年   415篇
  1999年   337篇
  1998年   330篇
  1997年   305篇
  1996年   305篇
  1995年   273篇
  1994年   263篇
  1993年   286篇
  1992年   279篇
  1991年   281篇
  1990年   257篇
  1989年   248篇
  1988年   230篇
  1987年   200篇
  1986年   251篇
  1985年   345篇
  1984年   309篇
  1983年   310篇
  1982年   259篇
  1981年   249篇
  1980年   274篇
  1979年   238篇
  1978年   205篇
  1977年   198篇
  1976年   168篇
  1975年   156篇
  1974年   143篇
  1973年   127篇
  1972年   98篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
881.
A field study was conducted to test the effectiveness of intergroup contact (Allport, The nature of prejudice, 1954) as a predictor of explicit and implicit attitudes toward immigrants and to examine the processes driving its effects. Participants were Italian businessmen owning small and medium enterprises in Northern Italy who had daily contact with their immigrant workers. We tested a model in which contact ameliorated explicit attitudes, measured as support for social policies toward immigration, through reduced negative outgroup stereotypes. Furthermore, we predicted that contact would have a direct, unmediated effect on improved implicit attitudes toward immigrants, assessed with an Implicit Association Test (Greenwald et al., J Personal Soc Psychol 74:1464–1480, 1998). The results were fully consistent with predictions, thus providing strong support for the contact hypothesis at both an explicit and at an implicit level. The lack of correlation between explicit and implicit attitudes supports dual-process models, suggesting that the two types of attitudes are formed through different processes. The theoretical and practical implications of the findings are discussed.  相似文献   
882.
Due to the impact of knowledge-based economies, all countries strive to foster creative education. Research has demonstrated that creativity is influenced both by individual characteristics and by the environment. Previous research examining creative teaching by teachers in Taiwan has typically focused on the relationships between creative teaching and innovative personal characteristics, school leaders’ behaviors, and internal motivation. The purpose of this study was to move beyond prior research to investigate the relationship between creative teaching behaviors and innovation-fostering elements of the organizational climate in schools. In addition, we examined the impact on teacher creativity of urban versus rural school location.  相似文献   
883.
A Pairwise Majority Rule Winner (PMRW) exists for a voting situation if some candidate can defeat each of the remaining candidates by Pairwise Majority Rule. The PMRW would be very appropriate for selection as the winner of an election, but it is well known that such a candidate does not always exist. This paper concludes a series of studies regarding the probability that a PMRW should be expected to exist in three-candidate elections, by introducing the notion of a strong measures of mutually coherent group preferences. In order for voting situations to be reasonably expected to fail to have a PMRW in a three-candidate election, voters’ preferences must be generated in an environment that is far removed from the situation in which there is a strong-overall-unifying candidate. So far removed, that it is extremely unlikely that a PMRW will not exist in voting situations with large electorates for a small number of candidates.  相似文献   
884.
We use daily price data from the Egyptian stock market and a Loser portfolio of 20 IPOs from the late 1990s that experienced dramatic 1-day price falls in the period 2004 to 2007 to estimate a 2-way fixed effects model of CARs. Observable covariates are company size and turnover growth and unobservables company and period fixed effects. Our results provide evidence of significant price reversal over the first 40 post-event days. Firm size is negatively correlated with post-event CARs, consistently with the argument that small firms have a stronger tendency to price-reverse due to greater informational opacity. But permanent, unobservable company-specific factors, account for a much larger percentage of post-event variation in stock prices and indicate an underlying heterogeneity in investor responses to initial price falls not uncovered before in the literature. Strong negative company effects following a price fall are found to presage reinforcing ‘long term’ price falls and strong positive company effects to presage countervailing ‘long term’ price reversals. At the extremes these company effects are sufficiently large to suggest that a trading strategy based on them would be profitable.  相似文献   
885.
886.
The seasonal patterns observed on Monday stock returns are still unexplained by different asset pricing models. We attempt to fill this gap in the finance literature by using the Fama-French (Journal of Financial Economics 33:3–56, 1993) risk factors to explain the Monday seasonal. The results in the study show that Monday returns are explained by risk factors such as the market return, the size of the firms, and the book-to-market ratios of firms.  相似文献   
887.
Some economists use an export tax, which alters the domestic relative price of exports, to model a voluntary export restraint, which is a restriction on the quantity of exports with restriction-induced rents accruing to the exporting country. Implicit in this approach is the presumption that the two policies are equivalent. In a very general model that allows for a finite number of goods and factors and intermediated goods and joint production, we demonstrate that, in general, this is, in fact, not the case. Specifically, from the exporting country’s perspective, the real income effects of the two policies are nonequivalent.  相似文献   
888.
A nonstationary simultaneous autoregressive model \({X^{(n)}_k=\alpha \Big(X^{(n)}_{k-1}+X^{(n)}_{k+1}\Big)+\varepsilon_k, k=1, 2, \ldots , n-1}\), is investigated, where \({X^{(n)}_0}\) and \({X^{(n)}_n}\) are given random variables. It is shown that in the unstable case α = 1/2 the least squares estimator of the autoregressive parameter converges to a functional of a standard Wiener process with a rate of convergence n 2, while in the stable situation |α| < 1/2 the estimator is biased but asymptotically normal with a rate n 1/2.  相似文献   
889.
Nonlinear regression models have been widely used in practice for a variety of time series and cross-section datasets. For purposes of analyzing univariate and multivariate time series data, in particular, smooth transition regression (STR) models have been shown to be very useful for representing and capturing asymmetric behavior. Most STR models have been applied to univariate processes, and have made a variety of assumptions, including stationary or cointegrated processes, uncorrelated, homoskedastic or conditionally heteroskedastic errors, and weakly exogenous regressors. Under the assumption of exogeneity, the standard method of estimation is nonlinear least squares. The primary purpose of this paper is to relax the assumption of weakly exogenous regressors and to discuss moment-based methods for estimating STR models. The paper analyzes the properties of the STR model with endogenous variables by providing a diagnostic test of linearity of the underlying process under endogeneity, developing an estimation procedure and a misspecification test for the STR model, presenting the results of Monte Carlo simulations to show the usefulness of the model and estimation method, and providing an empirical application for inflation rate targeting in Brazil. We show that STR models with endogenous variables can be specified and estimated by a straightforward application of existing results in the literature.  相似文献   
890.
Public procurement partnerships represent a new approach to conducting government acquisition. These partnerships are predicated on the notion that governments today simply lack the requisite knowledge, skills and financing to provide core public services and acquire sophisticated services, IT and knowledge development by themselves. Instead, governments need to enlist the collective energies of the governmental, business and non-profit (third) sectors. This research looks at the concept of public procurement partnerships in the United States and the major trends promoting their use. Two case examples of public procurement partnerships are presented; one from the perspective of a government partner, the other from the perspective of a private (third) sector partner.  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