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   145385篇
  免费   4110篇
  国内免费   76篇
财政金融   26559篇
工业经济   12099篇
计划管理   23542篇
经济学   31005篇
综合类   2559篇
运输经济   1067篇
旅游经济   2570篇
贸易经济   24719篇
农业经济   6695篇
经济概况   18488篇
信息产业经济   10篇
邮电经济   258篇
  2021年   1155篇
  2020年   1882篇
  2019年   2529篇
  2018年   2448篇
  2017年   2766篇
  2016年   2870篇
  2015年   2407篇
  2014年   3755篇
  2013年   15842篇
  2012年   4934篇
  2011年   5173篇
  2010年   4583篇
  2009年   4937篇
  2008年   4707篇
  2007年   3962篇
  2006年   4315篇
  2005年   4219篇
  2004年   3305篇
  2003年   3057篇
  2002年   3001篇
  2001年   2767篇
  2000年   2630篇
  1999年   2481篇
  1998年   2329篇
  1997年   2365篇
  1996年   2208篇
  1995年   2008篇
  1994年   2011篇
  1993年   1978篇
  1992年   2036篇
  1991年   1943篇
  1990年   1830篇
  1989年   1679篇
  1988年   1608篇
  1987年   1609篇
  1986年   1693篇
  1985年   2478篇
  1984年   2350篇
  1983年   2151篇
  1982年   2004篇
  1981年   1941篇
  1980年   1902篇
  1979年   1844篇
  1978年   1629篇
  1977年   1619篇
  1976年   1384篇
  1975年   1275篇
  1974年   1187篇
  1973年   1186篇
  1972年   894篇
排序方式: 共有10000条查询结果,搜索用时 484 毫秒
911.
Evaluating FOMC forecasts   总被引:1,自引:0,他引:1  
Monetary policy outcomes have improved since the early 1980s. One factor contributing to the improvement is that Federal Reserve policymakers began reporting economic forecasts to Congress in 1979. These forecasts indicate what the Federal Open Market Committee (FOMC) members think will be the likely consequence of their policies. We evaluate the accuracy of the FOMC forecasts relative to private sector forecasts, the forecasts of the Research Staff at the Board of Governors, and a naïve alternative. We find that the FOMC output forecasts were better than the naïve model and at least as good as those of the private sector and the Fed staff. The FOMC inflation forecasts were more accurate than the private sector forecasts and the naïve model; for the period ending in 1996, however, they were not as accurate as Fed staff inflation forecasts.  相似文献   
912.
Predicting the geo-temporal variations of crime and disorder   总被引:2,自引:0,他引:2  
Traditional police boundaries—precincts, patrol districts, etc.—often fail to reflect the true distribution of criminal activity and thus do little to assist in the optimal allocation of police resources. This paper introduces methods for crime incident forecasting by focusing upon geographical areas of concern that transcend traditional policing boundaries. The computerised procedure utilises a geographical crime incidence-scanning algorithm to identify clusters with relatively high levels of crime (hot spots). These clusters provide sufficient data for training artificial neural networks (ANNs) capable of modelling trends within them. The approach to ANN specification and estimation is enhanced by application of a novel and noteworthy approach, the Gamma test (GT).  相似文献   
913.
914.
915.
916.
This paper defines business ethics as a seriesof behaviors that adhere to values held by theindividual manager, the manager's supervisorsand subordinates, general society and, mostimportantly, the manager's customers andclients. The concept of business ethics isexplored through several levels of businessorganizations and operating environments.The paper then examines recent evidence of thedecline in business ethics by noting a fewexamples involving Beech-Nut, Hertz, MichaelMilken, E.F. Hutton, Sears, Salomon Brothers,Dalkon Shield, Exxon Valdez, S&L scandal,brokerage analysts. Surveys are cited toindicate that the American public believes thatbusiness ethics are declining.To further analyze the topic, the authorreports on a series of structured interviewswith managers in a variety of organizations.Fourteen senior managers were interviewed: 4from large county government, 3 from stategovernment, 4 from large corporations, 3 fromsmall businesses. The managers were asked theiropinions concerning the decline of businessethics, and for their recommendations topossibly retard the decline. All managers saidthey believed that ethics are in decline andthat the public believes ethics are declining.The recommendations for retarding or reversingthe decline yielded several suggestions: teachethics in schools and business organizations,develop and enforce Codes of Ethical Conductwithin all organizations, establish bettermonitoring and reporting mechanisms, and hireethical managers.The paper builds on theinterview results by coupling the managers'remarks with admonitions from many authors:while teaching ethics and Codes of EthicalConduct are important, the most importantfactor is the ethical behavior of managers(leaders). Ethical leadership is fundamentalsince ethical behavior is an individual – not acorporate – matter. In practice, ethics is notsomething that a manager ``does'; it issomething that the manager ``is.'  相似文献   
917.
918.
The truncated Poisson regression model is used to arrive at point and interval estimates of the size of two offender populations, i.e. drunk drivers and persons who illegally possess firearms. The dependent capture–recapture variables are constructed from Dutch police records and are counts of individual arrests for both violations. The population size estimates are derived assuming that each count is a realization of a Poisson distribution, and that the Poisson parameters are related to covariates through the truncated Poisson regression model. These assumptions are discussed in detail, and the tenability of the second assumption is assessed by evaluating the marginal residuals and performing tests on overdispersion. For the firearms example, the second assumption seems to hold well, but for the drunk drivers example there is some overdispersion. It is concluded that the method is useful, provided it is used with care.  相似文献   
919.
920.
A bilinear multivariate errors-in-variables model is considered. It corresponds to an overdetermined set of linear equations AXB=C, A∈ℝm×n, B∈ℝp×q, in which the data A, B, C are perturbed by errors. The total least squares estimator is inconsistent in this case.  An adjusted least squares estimator is constructed, which converges to the true value X, as m →∞, q →∞. A small sample modification of the estimator is presented, which is more stable for small m and q and is asymptotically equivalent to the adjusted least squares estimator. The theoretical results are confirmed by a simulation study. Acknowledgements. We thank two anonymous reviewers for their suggestions and corrections.? A. Kukush is supported by a postdoctoral research fellowship of the Belgian office for Scientific, Technical and Cultural Affairs, promoting Scientific and Technical Collaboration with Central and Eastern Europe.? S. Van Huffel is a full professor with the Katholieke Universiteit Leuven.? I. Markovsky is a research assistant with the Katholieke Universiteit Leuven.? This paper presents research results of the Belgian Programme on Interuniversity Poles of Attraction (IUAP V-22), initiated by the Belgian State, Prime Minister's Office – Federal Office for Scientific, Technical and Cultural Affairs of the Concerted Research Action (GOA) projects of the Flemish Government MEFISTO-666 (Mathematical Engineering for Information and Communication Systems Technology), of the IDO/99/03 project (K.U. Leuven) “Predictive computer models for medical classification problems using patient data and expert knowledge”, of the FWO projects G.0078.01, G.0200.00, and G0.0270.02.? The scientific responsibility is assumed by its authors.  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