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   34711篇
  免费   649篇
  国内免费   1篇
财政金融   6578篇
工业经济   2513篇
计划管理   5336篇
经济学   7530篇
综合类   458篇
运输经济   226篇
旅游经济   615篇
贸易经济   5275篇
农业经济   1729篇
经济概况   5016篇
信息产业经济   1篇
邮电经济   84篇
  2021年   201篇
  2020年   355篇
  2019年   557篇
  2018年   660篇
  2017年   701篇
  2016年   710篇
  2015年   434篇
  2014年   741篇
  2013年   3449篇
  2012年   1017篇
  2011年   1099篇
  2010年   918篇
  2009年   1013篇
  2008年   1019篇
  2007年   872篇
  2006年   793篇
  2005年   691篇
  2004年   680篇
  2003年   664篇
  2002年   699篇
  2001年   629篇
  2000年   654篇
  1999年   656篇
  1998年   598篇
  1997年   594篇
  1996年   586篇
  1995年   518篇
  1994年   518篇
  1993年   577篇
  1992年   574篇
  1991年   562篇
  1990年   466篇
  1989年   447篇
  1988年   422篇
  1987年   423篇
  1986年   424篇
  1985年   678篇
  1984年   644篇
  1983年   591篇
  1982年   542篇
  1981年   511篇
  1980年   568篇
  1979年   498篇
  1978年   409篇
  1977年   409篇
  1976年   330篇
  1975年   364篇
  1974年   306篇
  1973年   302篇
  1972年   209篇
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
971.
Policymakers often question whether not-for-profit (NFP) hospitals provide enough charity care to justify tax advantages. In 1993, Texas enacted legislation requiring NFP hospitals to provide certain community benefits at levels set forth in specific criteria to retain tax-exempt status; this paper focuses on the effect of the legislation’s requirement that NFP hospitals spend a minimum of 4% of net patient revenue on charity care. We also study a modification of the law passed in 1995, which allows the deduction of bad debts expense when calculating net patient revenue. This change effectively lowers required charity care spending, and our study considers whether Texas hospitals responded by reducing charity care spending.  相似文献   
972.
We extend the benchmark nonlinear deterministic volatility regression functions of Dumas et al. (1998) to provide a semi-parametric method where an enhancement of the implied parameter values is used in the parametric option pricing models. Besides volatility, skewness and kurtosis of the asset return distribution can also be enhanced. Empirical results, using closing prices of the S&P 500 index call options (in one day ahead out-of-sample pricing tests), strongly support our method that compares favorably with a model that admits stochastic volatility and random jumps. Moreover, it is found to be superior in various robustness tests. Our semi-parametric approach is an effective remedy to the curse of dimensionality presented in nonparametric estimation and its main advantage is that it delivers theoretically consistent option prices and hedging parameters. The economic significance of the approach is tested in terms of hedging, where the evaluation and estimation loss functions are aligned.  相似文献   
973.
We investigate whether Australian fund managers are able to deliver persistent performance using Carhart’s (1997) four‐factor model. Short‐ and long‐term persistence is examined and the sample is also divided into unit trusts and superannuation funds. We do not find evidence of persistence in any sample of funds. We find that winner (loser) funds tend to hold past winner (loser) stocks. Winner and loser unit trusts both appear to have positive exposure to small stocks.  相似文献   
974.
Newly public companies must disclose significant risk factors in the offering prospectus. These disclosures are examples of “soft” or ambiguous information. Ambiguity models predict that investors will alter their portfolio weights and react to subsequent signals about such information. We test for these effects in a sample of 1,398 initial public offerings (IPOs) using word count ratios between soft and hard information as measures of ambiguity. We find a significant relationship between the soft information on risk and both initial and ex post measures of returns. These results support the view that soft information embeds ambiguity and that it influences investors’ portfolio choices.  相似文献   
975.
Universities and colleges continue to face constraints related to classroom space and faculty time, thus increasing the need to consider options such as hybrid courses that can leverage available resources. This article discusses the benefits of a hybrid course, as well as its design and implementation at a large, public university. In addition, for universities that use the introduction to risk and insurance course as a significant course for attracting majors, we identify the benefits for students from the use of hybrid courses, such as the variety of materials and activities utilized, as well as the flexibility in scheduling. This information may be useful in marketing the course so that it will be immediately attractive to students.  相似文献   
976.
This article investigates the natural hedging strategy to deal with longevity risks for life insurance companies. We propose an immunization model that incorporates a stochastic mortality dynamic to calculate the optimal life insurance–annuity product mix ratio to hedge against longevity risks. We model the dynamic of the changes in future mortality using the well‐known Lee–Carter model and discuss the model risk issue by comparing the results between the Lee–Carter and Cairns–Blake–Dowd models. On the basis of the mortality experience and insurance products in the United States, we demonstrate that the proposed model can lead to an optimal product mix and effectively reduce longevity risks for life insurance companies.  相似文献   
977.
Existing research suggests that, for a given firm, stock returns and bond prices are positively related, and this implies a negative relation between stock returns and bond spreads. In this paper, we show how takeover risk influences this relation. Bondholders of high-rated firms can suffer losses in a takeover, particularly if the takeover is largely funded with debt, resulting in a more positive (or less negative) correlation between stock returns and bond spread changes. Consistent with this notion and based on a large sample of data covering the period from 1980 to 2000, we find that high-rated firms which are likely to be taken over have a more positive correlation between stock returns and bond spread changes, while target firms with a poison put or an indebtedness covenant have a more negative correlation. Overall, our findings have implications for the pricing and hedging of bonds and default risk based financial products such as credit default swaps.  相似文献   
978.
Despite extensive monitoring, banking operations are often considered opaque, and despite explicit capital adequacy regulation, banks may have substantial discretion in their financing. Both monitoring and capital regulation have changed substantially over time, with the adoption of FDICIA being one important breakpoint. This article empirically studies seasoned equity offerings (SEOs) by banks to understand how opacity and capital regulation interact to determine the timing of bank SEOs and their market valuation. SEOs both by banks that are undercapitalized relative to regulatory standards and also well-capitalized banks are fully discretionary when it comes to SEOs, even before FDICIA. Both undercapitalized and well-capitalized banks experience similar and significantly negative stock price reactions to SEO announcements, and also have similar prior patterns of insider trading and similar economic drivers of the issuance decision. Moreover, post-SEO abnormal stock returns are similar to benchmark returns for both types of issuers in the long run, suggesting that, contrary to the well-documented evidence for industrial SEOs, investors understand the value implications of bank SEOs upon announcement. The evidence implies that undercapitalized banks' SEOs are more discretionary and that all bank SEOs are less opaque than implied by earlier studies.  相似文献   
979.
Blume and Goldstein (J Finance 52:221–244, 1997) suggest that quote competition between trading venues may diminish following tick size reductions. We test this suggestion by studying the competitive landscape in the NYSE-listed stocks before and after decimalization. We find that NBBO (National Best Bid and Offer) participation by non-NYSE venues declines following decimalization consistent with the prediction. At the same time, the importance of quote competitiveness in attracting order flow increases. In addition, although not as active in determining and maintaining the best quotes under decimals, non-NYSE venues become more active in price discovery. Finally, decimalization leads to lower trading costs and to smaller differences in trading costs across trading venues.  相似文献   
980.
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