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   8374篇
  免费   172篇
  国内免费   1篇
财政金融   1933篇
工业经济   632篇
计划管理   1261篇
经济学   1859篇
综合类   147篇
运输经济   49篇
旅游经济   143篇
贸易经济   1654篇
农业经济   270篇
经济概况   596篇
邮电经济   3篇
  2023年   35篇
  2021年   62篇
  2020年   95篇
  2019年   161篇
  2018年   138篇
  2017年   139篇
  2016年   166篇
  2015年   135篇
  2014年   155篇
  2013年   924篇
  2012年   253篇
  2011年   281篇
  2010年   261篇
  2009年   273篇
  2008年   296篇
  2007年   272篇
  2006年   267篇
  2005年   269篇
  2004年   239篇
  2003年   247篇
  2002年   224篇
  2001年   180篇
  2000年   186篇
  1999年   154篇
  1998年   173篇
  1997年   149篇
  1996年   146篇
  1995年   134篇
  1994年   135篇
  1993年   126篇
  1992年   124篇
  1991年   103篇
  1990年   98篇
  1989年   88篇
  1988年   76篇
  1987年   102篇
  1986年   93篇
  1985年   167篇
  1984年   144篇
  1983年   160篇
  1982年   104篇
  1981年   108篇
  1980年   95篇
  1979年   95篇
  1978年   98篇
  1977年   115篇
  1976年   95篇
  1975年   70篇
  1974年   48篇
  1973年   59篇
排序方式: 共有8547条查询结果,搜索用时 15 毫秒
31.
In response to the growth of online shopping, consumer groups from around the world participated in two mystery shopping exercises. These exercises, conducted during the Christmas holiday seasons of 1998 and 2000, involved buying a variety of products from web sites located both domestically and abroad. A number of serious problems were identified within the research, especially lack of disclosure of key consumer information and failures in delivering goods and refunding consumers when goods were returned. The research has been used by consumer organizations to enhance consumer education and to lobby governmental and self-regulatory bodies for greater consumer protection in the online environment.  相似文献   
32.
The Returns to Education: Microeconomics   总被引:8,自引:0,他引:8  
In this paper we focus on education as a private decision to invest in "human capital" and the estimation of the rate of return to that private investment. While the literature is replete with studies that estimate the rate of return using regression methods where the estimated return is obtained as the coefficient on a years of education variable in a log wage equation that contains controls for work experience and other individual characteristics, the issue is surrounded with difficulties. We outline the theoretical arguments underpinning the empirical developments and show that the evidence on private returns to the individual is compelling. Despite some of these issues surrounding the estimation of the return to schooling, our evidence, based on estimates from a variety of datasets and specifications, is that there is an unambiguously positive effect on the earnings of an individual from participation in education. Moreover, the size of the effect seems large relative to the returns on other investments.  相似文献   
33.
In-depth data analysis plus statistical modeling can produce inferentialcausal models. Their creation thus combines aspects of analysis by close inspection,that is, reason analysis and cross-tabular analysis, with statistical analysis procedures,especially those that are special cases of the generalized linear model (McCullaghand Nelder, 1989; Agresti, 1996; Lindsey, 1997). This paper explores some of the roots of this combined method and suggests some new directions. An exercise clarifies some limitations of classic reason analysis by showing how the cross tabulation of variables with controls for test factors may produce better inferences. Then, given the cross tabulation of several variables, by explicating Coleman effect parameters, logistic regressions, and Poisson log-linear models, it shows how generalized linear models provide appropriate measures of effects and tests of statistical significance. Finally, to address a weakness of reason analysis, a case-control design is proposed and an example is developed.  相似文献   
34.
A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
35.
Chief Executives from New Zealand's largest companies were surveyed to distinguish divesting and nondivesting companies, and to identify the relative importance of the factors and motives which led to the divestment of 208 business units in the period 1985 through 1990. The divesting companies were considerably larger and faster growing than nondivestors. The typical divestment was motivated by the need to convert unattractive assets into liquid form which could then be held to strengthen the balance sheet, or reinvested in either the core business or new areas.  相似文献   
36.
37.
Stochastic dominance efficiency criteria are used to rank the net farm return distributions for four different tillage systems under six different farm scenarios. Pairwise comparisons of tillage systems are carried over incremental upper and lower risk-aversion coefficient (RAC) bounds identified for each farm scenario, based on the size and spread of the outcome distributions to identify regions where dominance may switch between tillage systems. Ridge-till systems are generally the dominant tillage system for all farm scenarios considered. No-till systems on clay loam soils are more dominant in the risk-preferring range and less dominant in the risk-averse range, which relates to the relatively larger range of net return values and smaller mean net return values generated by this tillage system. Conversely, the moldboard plow and chisel plow systems are more dominant in risk-aversion intervals and less dominant in the risk-preferring intervals for clay loam soils. In sandy soil scenarios, the ridge-till and no-till systems are dominant over the two fall tillage systems for all farm sizes, indicating that these tillage systems are more competitive with conventional tillage systems in lighter soil type situations. A sensitivity analysis between moldboard plow and no-till systems indicates that no-till would dominate in risk-preferring intervals, and an increase in no-till net farm returns of 16 per acre would change dominance in favor of no-till in risk-averse interval space. On a utilisé les critères d'efficacitéà dominance stochastique pour classer les divers niveaux de recettes agricoles nettes dans quatre systèmes différents de travail du sol, selon six scénarios d'exploitation. Des comparaisons en paires des systèmes de travail ont été faites en regard de tranches croissantes des limites supérieures et inférieures du coefficient d'aversion du risque (CER), établies pour chaque scénario d'après l'importance et l'étendue des distributions du rendement, dans le but d'identifier les régions où la dominance serait susceptible de passer d'un système de travail à l'autre. Le système de travail sur billons était en général le système dominant dans tous les scénarios d'exploitation examinés. La culture sans travail du sol sur loam argileux était plus dominante dans les intervalles d'acceptation du resque et moins dominante dans les intervalles d'aversion du resque, cequi s'explique au fait que ce système de travail donne lieu à une fourchette relativement plus large, mais aussi à une moyenne plus faible du revenu net. À l'inverse, le labour à la charrue classique et au chisel dominait davantage dans les intervalles d'aversion du risque. Dans les sols sableux, le travail sur billons et la culture sans labour l'emportaient sur les deux autres régimes dans toutes les tailles d'exploitation, ce qui porte à croire que, dans les sols plus légers, ces régimes sont plus concurrentiels avec les systèmes classiques. L'analyse de sensibilité entre le labour à la charrue et les systèmes sans travail du sol montre que ces derniers dominent dans les intervalles d'acceptation du risque et qu'un accroissement du revenu agricole net de 16 /acre ferait glisser la dominance vers les intervalles d'aversion du risque.  相似文献   
38.
Announcements of syndication loans increase borrowers' shareholder wealth if they are revolving credit agreements but not if they are term loans. Share price responses to revolving credit announcements are positive and significant, whereas the wealth effect for term loans is negative and significant. The results show that announcements from both the financial press and commercial information providers can affect borrower share price reaction. Overall, single syndication announcements appear to be more newsworthy than multiple announcements reported in the financial press, and we find evidence of information leakage, post‐announcement drift, or both.  相似文献   
39.
Enterprise risk management (ERM) has captured the attention of risk management professionals and academics worldwide. Unlike the traditional "silo-based" approach to corporate risk management, ERM enables firms to benefit from an integrated approach to managing risk that shifts the focus of the risk management function from primarily defensive to increasingly offensive and strategic. Despite the heightened interest in ERM, little empirical research has been conducted on the topic. This study provides an initial attempt at identifying the determinants of ERM adoption. We construct a sample of firms that have signaled their use of ERM by appointing a Chief Risk Officer (CRO) who is charged with the responsibility of implementing and managing the ERM program. We use a logistic regression framework to compare these firms to a size- and industry-matched control sample. While our results suggest a general absence of differences in the financial and ownership characteristics of sample and control firms, we find that firms with greater financial leverage are more likely to appoint a CRO. This finding is consistent with the hypothesis that firms appoint CROs to reduce information asymmetry regarding the firm's current and expected risk profile.  相似文献   
40.
Trades and Quotes: A Bivariate Point Process   总被引:3,自引:0,他引:3  
This article formulates a bivariate point process to jointlyanalyze trade and quote arrivals. In microstructure models,trades may reveal private information that is then incorporatedinto new price quotes. This article examines the speed of thisinformation flow and the circumstances that govern it. A jointlikelihood function for trade and quote arrivals is specifiedin a way that recognizes that an intervening trade sometimescensors the time between a trade and the subsequent quote. Modelsof trades and quotes are estimated for eight stocks using Tradeand Quote database (TAQ) data. The essential finding for thearrival of price quotes is that information flow variables,such as high trade arrival rates, large volume per trade, andwide bid–ask spreads, all predict more rapid price revisions.This means prices respond more quickly to trades when informationis flowing so that the price impacts of trades and ultimatelythe volatility of prices are high in such circumstances.  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