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   138994篇
  免费   3888篇
  国内免费   2篇
财政金融   26518篇
工业经济   11454篇
计划管理   22471篇
经济学   30412篇
综合类   1495篇
运输经济   992篇
旅游经济   2595篇
贸易经济   22998篇
农业经济   6374篇
经济概况   17324篇
信息产业经济   10篇
邮电经济   241篇
  2021年   856篇
  2020年   1669篇
  2019年   2453篇
  2018年   2462篇
  2017年   2636篇
  2016年   2833篇
  2015年   2147篇
  2014年   3476篇
  2013年   15780篇
  2012年   4325篇
  2011年   4420篇
  2010年   3879篇
  2009年   4492篇
  2008年   4084篇
  2007年   3473篇
  2006年   3748篇
  2005年   3711篇
  2004年   3257篇
  2003年   3062篇
  2002年   3004篇
  2001年   2747篇
  2000年   2680篇
  1999年   2560篇
  1998年   2411篇
  1997年   2375篇
  1996年   2064篇
  1995年   2035篇
  1994年   2027篇
  1993年   2040篇
  1992年   2027篇
  1991年   1934篇
  1990年   1776篇
  1989年   1620篇
  1988年   1557篇
  1987年   1567篇
  1986年   1659篇
  1985年   2442篇
  1984年   2301篇
  1983年   2106篇
  1982年   1976篇
  1981年   1953篇
  1980年   1920篇
  1979年   1832篇
  1978年   1647篇
  1977年   1627篇
  1976年   1392篇
  1975年   1274篇
  1974年   1206篇
  1973年   1164篇
  1972年   877篇
排序方式: 共有10000条查询结果,搜索用时 809 毫秒
21.
Objective: This study was to determine if calcium fortification yields a higher price per serving in grocery store products. Researchers compared store brand to national brand grocery products in relation to cost in order to examine if calcium values were similar between store brand and national brand products. Methods: A total of 112 store brand and 211 national brand grocery products were collected from three low (national chain store), middle and high priced (Virginia and North Carolina regional store) grocery venues. Products were compared using price and calcium percentage per serving. ANOVA was used to determine between store brand and national brand for price per serving and calcium content, and between grocery venues. Results: National brand fortified products had a significantly lower mean price per serving when compared to national brand non-fortified products (p = 0.0002). There was no statistical difference between store brand fortified and non-fortified products (p = 0.9256). Low priced store brand products had the lowest mean price per serving ($0.34 ±0.24). Conclusions: This study found store brand products have similar calcium content as national brand products. Product cost was lower at low priced store compared to middle and high priced stores.  相似文献   
22.
Consumer “multihoming” (watching two TV channels, or buying two news magazines) has surprisingly important effects on market equilibrium and performance in (two‐sided) media markets. We show this by introducing consumer multihoming and advertising finance into the classic circle model of product differentiation. When consumers multihome (attend more than one platform), media platforms can charge only incremental value prices to advertisers. Entry or merger leaves consumer prices unchanged under consumer multihoming, but leaves advertiser prices unchanged under single‐homing: Multihoming flips the side of the market on which platforms compete. In contrast to standard circle results, equilibrium product variety can be insufficient under multihoming.  相似文献   
23.
In this paper, we study consumers with limited memory and examine the effects of their price categorization on the pricing strategies of competing firms. The valuations of consumers are assumed to be heterogeneous. We find that it is possible to observe price dispersion even when each firm charges a single price if the consumers categorize prices non‐optimally. Moreover, we demonstrate that the likelihood of a price dispersion outcome is reduced when consumers with limited memory set up the price categories optimally. These findings suggest that the consumers' limited memory and their sub‐optimal behavior, that is, their inability to choose price categories optimally can be a reason for observed price dispersion.  相似文献   
24.
25.
We study the effect of the educational diversity of managers on the performance of team‐managed mutual funds using a large sample of U.S. equity funds from 1994 to 2013. We consider diversity in terms of both final educational degree and field of educational specialisation. We find that, in general, both types of diversity have a positive impact on fund performance, and our results are robust over a wide range of performance metrics and changes in market conditions.  相似文献   
26.
Review of Quantitative Finance and Accounting - We examine how changes in dividend policy in 2008 as the financial crisis was unfolding influenced firm risk-adjusted returns in the following years....  相似文献   
27.
Abstract

Traditional warranty analysis focuses on the reliability of a product and offers warranty designs that compensate a consumer if the item fails. We introduce the concept of a performance-based warranty (PBW) that guarantees that a product will operate at or above some baseline level of performance, such as a minimum energy efficiency for an appliance. We illustrate how consumer behavior can change in the presence of a PBW and define the parameters for which a manufacturer may increase revenue. Finally, we present an algorithm to solve for the optimal PBW design given a consumer’s belief about the expected performance of the product.  相似文献   
28.
President Biden was sworn in on January 20, 2021 after a 4‐year term by President Trump. Certainly, Trump's norm breaking presidency impacted Canada in significant ways and the agricultural sector was no exception. In this issue, we have a set of four short articles discussing the possible implications on Canadian agriculture of transitioning from a Trump to Biden presidency. Issues related to Canada‐U.S. agricultural trade, political norms and uncertainty, U.S. domestic support, participation in trade agreements, and U.S.‐China relations are all considered.  相似文献   
29.
30.
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