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   14681篇
  免费   280篇
财政金融   2872篇
工业经济   1090篇
计划管理   2299篇
经济学   3102篇
综合类   519篇
运输经济   118篇
旅游经济   282篇
贸易经济   2146篇
农业经济   685篇
经济概况   1837篇
邮电经济   11篇
  2021年   73篇
  2020年   174篇
  2019年   246篇
  2018年   257篇
  2017年   281篇
  2016年   250篇
  2015年   199篇
  2014年   302篇
  2013年   1600篇
  2012年   367篇
  2011年   461篇
  2010年   391篇
  2009年   388篇
  2008年   441篇
  2007年   360篇
  2006年   272篇
  2005年   289篇
  2004年   284篇
  2003年   300篇
  2002年   299篇
  2001年   305篇
  2000年   351篇
  1999年   260篇
  1998年   286篇
  1997年   289篇
  1996年   254篇
  1995年   237篇
  1994年   253篇
  1993年   288篇
  1992年   259篇
  1991年   247篇
  1990年   234篇
  1989年   194篇
  1988年   184篇
  1987年   179篇
  1986年   192篇
  1985年   248篇
  1984年   312篇
  1983年   259篇
  1982年   249篇
  1981年   264篇
  1980年   234篇
  1979年   244篇
  1978年   201篇
  1977年   189篇
  1976年   174篇
  1975年   137篇
  1974年   139篇
  1973年   125篇
  1972年   84篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Abstract. This research re-examines whether there are differences in the forecast accuracy of financial analysts through a comparison of their annual earnings per share forecasts. The comparison of analyst forecast accuracy is made on both an ex post (within sample) and an ex ante (out of sample) basis. Early examinations of this issue by Richards (1976), Brown and Rozeff (1980), O'Brien (1987), Coggin and Hunter (1989), O'Brien (1990), and Butler and Lang (1991) were ex post and suggest the absence of analysts who can provide relatively more accurate forecasts over multiple years. Contrary to the results of prior research and consistent with the belief in the popular press, we document that differences do exist in financial analysts' ex post forecast accuracy. We show that the previous studies failed to find differences in forecast accuracy due to inadequate (or no) control for differences in the recency of forecasts issued by the analysts. It has been well documented in the literature that forecast recency is positively related to forecast accuracy (Crichfield, Dyckman, and Lakonishok 1978; O'Brien 1988; Brown 1991). Thus, failure to control for forecast recency may reduce the power of tests, making it difficult to reject the null hypothesis of no differences in forecast accuracy even if they do exist. In our analysis, we control for the differences in recency of analysts' forecasts using two different approaches. First, we use an estimated generalized least squares estimation procedure that captures the recency-induced effects in the residuals of the model. Second, we use a matched-pair design whereby we measure the relative forecast accuracy of an analyst by comparing his/her forecast error to the forecast error of another randomly selected analyst making forecasts for the same firm in the same year on or around the same date. Using both approaches, we find that differential forecast accuracy does exist amongst analysts, especially in samples with minimum forecast horizons of five and 60 trading days. We show that these differences are not attributable to differences in the forecast issuance frequency of the financial analysts. In sum, after controlling for firm, year, forecast recency, and forecast issuance frequency of individual analysts, the analyst effect persists. To validate our findings, we examine whether the differences in the forecast accuracy of financial analysts persist in holdout periods. Analysts were assigned a “superior” (“inferior”) status for a firm-year in the estimation sample using percentile rankings on the distribution of absolute forecast errors for that firm-year. We use estimation samples of one- to four-year duration, and consider two different definitions of analyst forecast superiority. Analysts were classified as firm-specific “superior” if they maintained a “superior” status in every year of the estimation sample. Furthermore, they were classified as industry-specific “superior” if they were deemed firm-specific “superior” with respect to at least two firms and firm-specific “inferior” with respect to no firm in that industry. Using either definition, we find that analysts classified as “superior” in estimation samples generally remain superior in holdout periods. In contrast, we find that analysts identified as “inferior” in estimation samples do not remain inferior in holdout periods. Our results suggest that some analysts' earnings forecasts should be weighted higher than others when formulating composite earnings expectations. This suggestion is predicated on the assumption that capital markets distinguish between analysts who are ex ante superior, and that they utilize this information when formulating stock prices. Our study provides an ex ante framework for identifying those analysts who appear to be superior. When constructing weighted forecasts, a one-year estimation period should be used because we obtain the strongest results of persistence in this case.  相似文献   
12.
This paper applies principles of transition to land tenure and squatting in South Africa. Political transition in South Africa reassigned political property rights, which produced contestable, and rent‐seeking incentives for squatting as a means to privatize land and redistribute wealth. Government failure to establish and protect private property rights in a squatter camp resulted in common‐pool problems that resisted private and public resolution with consequent rent dissipation and social loss. In response to this retreat from duty, informal agents emerged to claim their own share of the prize. Without enforceable rules of capture, the growth of squatter camps in South Africa will continue. JEL classification: D7, H8, K1, K4, R1, R4.  相似文献   
13.
14.
15.
16.
17.
18.
A growing awareness of workplace hazards and identification of airborne contaminants, coupled with a changing safety and health regulatory environment, created an unexpected demand for new and innovative respirators in the early 1980s. 3M's Occupational Health and Environmental Safety Division broke new ground by taking the team concept further than ever before in the company. The division's Action Teams successfully designed, built and introduced products in less than half the time it would have taken previously. Robert Hershock, Charles Cowman and Douglas Peters describe how 3M learned important lessons about team selection, training, performance and motivation, the importance of project sponsors, and the role of middle management.  相似文献   
19.
20.
Chris Cooper, of Surrey University's Department of Management Studies for Tourism and Hotel Industries, describes the uses and significance of the technique of interpretation in providing an interface between the tourist destination and the visitor. Interpretation can enhance the visitor experience by making the attributes of the resort more comprehensible.  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