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   2209篇
  免费   128篇
  国内免费   15篇
财政金融   604篇
工业经济   78篇
计划管理   369篇
经济学   433篇
综合类   154篇
运输经济   11篇
旅游经济   12篇
贸易经济   432篇
农业经济   115篇
经济概况   144篇
  2024年   8篇
  2023年   48篇
  2022年   17篇
  2021年   51篇
  2020年   94篇
  2019年   95篇
  2018年   75篇
  2017年   103篇
  2016年   94篇
  2015年   86篇
  2014年   127篇
  2013年   212篇
  2012年   154篇
  2011年   128篇
  2010年   99篇
  2009年   102篇
  2008年   103篇
  2007年   109篇
  2006年   115篇
  2005年   83篇
  2004年   81篇
  2003年   58篇
  2002年   54篇
  2001年   46篇
  2000年   55篇
  1999年   29篇
  1998年   25篇
  1997年   20篇
  1996年   20篇
  1995年   17篇
  1994年   12篇
  1993年   5篇
  1992年   9篇
  1991年   10篇
  1990年   1篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
排序方式: 共有2352条查询结果,搜索用时 31 毫秒
41.
We identify farms’ optimal investment path in capital assets and compare it with their actual investment to assess the direction and extent of deviation from the optimal investment. A probit model is further used to investigate the determinants of the probability that a farmer over‐ or under‐invests in capital assets. We use a panel dataset of Dutch dairy farms over the period 2003–2013, and find that most farms under‐invest in capital assets during the study period. Although the number of farms that had over‐invested in capital assets is relatively small, these farms account for the biggest share of total investment in capital assets. The probit results show that liquidity, agricultural support payments, age, land tenure and standard output size are important variables explaining the likelihood of over‐and under‐investment.  相似文献   
42.
This paper examines the wealth maximisation and preservation effects of including commercial real estate in retirement-phase portfolio management. Prior research addresses the role of real estate during the wealth-accumulation phase of the investor lifecycle; however, little is known about the contribution of real estate during the invest-and-spend, or decumulation, phase. To address this issue, we estimate short-fall risk based on the widely known 4% Rule. We use pricing data for multiple asset classes and simulation techniques, combined with a robust correlation structure, to examine: short-fall risk sensitivity to alternative spending rules; the impact of public vs. private real estate allocations; wealth preservation as an investment objective; and the effect of real estate on upside, or wealth maximisation, potential. We find short-fall risk in a decumulation portfolio decreases with substantial allocations to real estate. This result holds for a portfolio including either public or private real estate. Additionally, and under most conditions, the best performing decumulation-phase portfolios include a real estate allocation with both public and private real estate exposure. These results have significant implications for investors, whether they be retirees, plan administrators or endowments, as well as financial economists studying the lifecycle of investment decisions.  相似文献   
43.
针对佛冈县的土地生态的实际状况,基于"驱动力-压力-状态-影响-响应"(DPSIR)模型,构建土地生态安全评价指标体系,运用最优组合赋权法确定指标权重及土地生态安全综合评价模型对该区域进行评价。结果表明:1998—2008年佛冈县土地生态安全整体状况不断改善,生态安全综合指数从1998年的0.2567增至2008年的0.5858,生态安全水平处在从"风险级"状态转向"比较安全"状态的过程;从相关性分析来看,响应指标对土地生态安全水平的提高起主要的作用,但随着社会经济的加速发展,需要协调好各方面的矛盾,缓解资源环境的压力,使得土地生态环境朝着更好的方向迈进。  相似文献   
44.
In this paper, we study perpetual American call and put options in an exponential Lévy model. We consider a negative effective discount rate that arises in a number of financial applications including stock loans and real options, where the strike price can potentially grow at a higher rate than the original discount factor. We show that in this case a double continuation region arises and we identify the two critical prices. We also generalize this result to multiple stopping problems of Swing type, that is, when successive exercise opportunities are separated by i.i.d. random refraction times. We conduct an extensive numerical analysis for the Black–Scholes model and the jump‐diffusion model with exponentially distributed jumps.  相似文献   
45.
Large consumer goods firms manage and market an assortment of brands and consistently deal with strategic challenges related to brand portfolio management, such as creating or acquiring brands, growing brand equity, managing brands in the portfolio and deleting brands. There is substantial research on several areas of brand portfolio management except in the area of brand deletion. This situation exists despite the fact that deleting weak brands has important implications for a firm and its brand portfolio. Therefore, it is critical to understand why firms delete brands from their portfolios. This research applies a qualitative approach using semi-structured interviews and thematic analysis in the context of firms that adopt a ‘house of brands’ brand architecture and presents findings guided by the strategic decision-making literature.  相似文献   
46.
The bid and ask quotes as well as portfolio selection decisions of gold dealers who face a gold price risk are investigated within a continuous-time framework. The research integrates into a systematic analysis the decision of asset allocation in financial economics as well as the decision of a bid–ask spread in a market microstructure. The holding rate of gold is correlated to the intensity and jump size of the Poisson process, which is a hedging demand for gold assets against the risk of extreme events. According to empirical analysis from the gold service industries, the gold spread return is related to the expected return, volatility and jump risks of gold prices.  相似文献   
47.
We examine the co-movement in daily returns of USD–INR, EUR–INR, GBP–INR, and JPY–INR currency pair futures contracts traded on the National Stock Exchange of India (NSE) using the wavelet cohesion approach. This study contributes to the literature by examining the scantly studied area of co-movement in exchange rates and using the wavelet approach, which allows us to analyse time–frequency-wise co-movement of the time series. The empirical results indicate that the currency futures markets are nearly perfectly integrated in the long run (monthly, quarterly and biannual scales) offering little potential gains from international portfolio diversification. The discrepancies between currency futures markets are small and almost fade away within 3–6 months. Moreover, international currency diversification might offer relatively higher potential gains at intraweek, weekly, and fortnightly time horizons owing to lower correlations among the currencies under consideration. Finally, our multiple-wavelet correlation and cross-correlation analysis shows that GBP acts as a potential leader/follower across scales. The results of our analysis indicate the dynamic pattern of co-movement among the major currency futures contracts, which provides several implications for portfolio managers and international investors participating in the Indian market.  相似文献   
48.
Off‐farm work is a widespread, two‐edged, phenomenon that can help both the survival and the demise of small‐ and medium‐sized agricultural exploitations. Given the prevalence of poverty in rural areas, nonfarm income has been credited with helping farmers to survive. But the observed shrinking of rural areas has also raised the question of whether off‐farm work is pulling farmers permanently away from farming. This paper explores the impact of farmer characteristics on the decision to work off‐farm in developing countries where this phenomenon has been largely neglected. A review of theory and prior empirical work suggests four main hypotheses which we test empirically. The results suggest that while some farmer characteristics appear to be universal, others appear to be country‐ or culture‐specific.  相似文献   
49.
Many optimization-based portfolio rules fail to beat the simple 1/N rule out-of-sample because of parameter uncertainty. In this paper we suggest a grouping strategy in which we first form groups of equally weighted stocks and then optimize over the resulting groups only. This strategy aims at balancing the trade-off between the benefits from optimization and the losses from estimation risk. We rely on Monte-Carlo simulations to illustrate the performance of the strategy, and we derive the optimal group size for a simplified setup. Furthermore, we show that estimation risk also has an impact via the criterion by which the assets are sorted into groups (like the expected excess returns or betas), but does not negate the grouping approach. We relate our work to linear asset pricing models, and we conduct out of sample back-tests in order to confirm the validity of our grouping strategy empirically.  相似文献   
50.
我国城市土地优化配置研究演进与展望   总被引:3,自引:1,他引:3  
谢正峰  董玉祥 《经济地理》2011,31(8):1364-1369
通过文献分析法,将我国城市土地优化配置研究发展历程划分为3个阶段:城市土地优化配置研究的萌芽阶段(1978—1993);城市土地优化配置研究框架的初步形成阶段(1994—2000);城市土地优化配置技术和方法的发展阶段(2001年以来)。研究认为我国城市土地优化配置研究受到经济体制改革的影响,研究逐渐从优化配置的理论过度到优化配置技术和方法,城市土地利用空间配置的综合研究欠缺,城市土地优化配置的微观研究还有待加强。今后,城市土地优化配置研究包括城市土地空间优化配置、城市土地优化配置的外部效应、城市与区域土地利用关系等方面,应进一步加强和突破。  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