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   7649篇
  免费   306篇
  国内免费   61篇
财政金融   2063篇
工业经济   307篇
计划管理   1507篇
经济学   1482篇
综合类   522篇
运输经济   112篇
旅游经济   125篇
贸易经济   1038篇
农业经济   358篇
经济概况   502篇
  2024年   7篇
  2023年   146篇
  2022年   87篇
  2021年   194篇
  2020年   314篇
  2019年   273篇
  2018年   252篇
  2017年   325篇
  2016年   303篇
  2015年   218篇
  2014年   441篇
  2013年   832篇
  2012年   355篇
  2011年   437篇
  2010年   364篇
  2009年   382篇
  2008年   455篇
  2007年   385篇
  2006年   398篇
  2005年   356篇
  2004年   278篇
  2003年   207篇
  2002年   163篇
  2001年   152篇
  2000年   137篇
  1999年   120篇
  1998年   77篇
  1997年   88篇
  1996年   60篇
  1995年   43篇
  1994年   34篇
  1993年   23篇
  1992年   15篇
  1991年   22篇
  1990年   9篇
  1989年   4篇
  1988年   6篇
  1987年   5篇
  1986年   2篇
  1985年   14篇
  1984年   16篇
  1983年   8篇
  1982年   5篇
  1981年   2篇
  1980年   1篇
  1979年   1篇
排序方式: 共有8016条查询结果,搜索用时 15 毫秒
991.
European call options are priced when the uncertainty driving the stock price follows the V. G. stochastic process (Madan and Seneta 1990). the incomplete markets equilibrium change of measure is approximated and identified using the log return mean, variance, and kurtosis. an exact equilibrium interpretation is also provided, allowing inference about relative risk aversion coefficients from option prices. Relative to Black-Scholes, V. G. option values are higher, particularly so for out of the money options with long maturity on stocks with high means, low variances, and high kurtosis.  相似文献   
992.
Sir Francis Galton introduced median regression and the use of the quantile function to describe distributions. Very early on the tradition moved to mean regression and the universal use of the Normal distribution, either as the natural ‘error’ distribution or as one forced by transformation. Though the introduction of ‘quantile regression’ refocused attention on the shape of the variability about the line, it uses nonparametric approaches and so ignores the actual distribution of the ‘error’ term. This paper seeks to show how Galton's approach enables the complete regression model, deterministic and stochastic elements, to be modelled, fitted and investigated. The emphasis is on the range of models that can be used for the stochastic element. It is noted that as the deterministic terms can be built up from components, so to, using quantile functions, can the stochastic element. The model may thus be treated in both modelling and fitting as a unity. Some evidence is presented to justify the use of a much wider range of distributional models than is usually considered and to emphasize their flexibility in extending regression models.  相似文献   
993.
对小企业的研究应该超越那种仅把其视为大企业"迷你版"的研究范式.基于不同研究视角,从小企业固有独特性基础上对小企业成功因素的研究形成了五种典型的研究模式,这包括单因素研究、分行业研究、成败企业对比性研究、利益相关者角度研究和综合分析性研究.  相似文献   
994.
This article demonstrates that a dual pair of input-output price and quantity models, taken together, constitutes a composite network flow model. The network flow model has become a dominant analytical tool within the fields of operations analysis and electrical engineering, and the aim of the article is to enable input-output users within non-standard applications to take advantage of the large body of literature within these disciplines. Through a simple example it is shown that the solution of a dual pair of input-output models is a special case of the general problem of finding a minimum cost circulation in a transportation network. Second, it is shown that the common method of determining quantities and prices in input-output models is identical to the classical node method for determination of currents and voltages in an electrical network. The theory of transportation networks offers well developed methods for analysis of capacity constraints on the network flows, while the theory of electrical networks supplies methods for analysis of models with price sensitivities and for dynamic analysis. In addition, the elegant symmetry of currents and voltages in electrical networks contributes significantly to a better understanding of the logical relationship between price and quantity models.  相似文献   
995.
The note deals with the pricing of American options related to foreign market equities. the form of the early exercise premium representation of the American option's price in a stochastic interest rate economy is established. Subsequently, the American fixed exchange rate foreign equity option and the American equity-linked foreign exchange option are studied in detail.  相似文献   
996.
The paper deals with the question of how to include time dependent explanatory variables at the context-level in multilevel event history models. In general, context-level explanatory variables in multilevel models are assumed to be time constant. Only time constant context-level explanatory variables perform the task of reducing context-level error variance. Thus, it will be suggested that the analysis should be extended to a three-level model. In this model, time periods of persons constitute level 1 units, time periods of contexts constitute level 2 units and the contexts themselves constitute level 3 units – in which in turn level 2 units are clustered. Considering mobility between local labour markets as an example, four different ways of modelling time varying context-level variables are compared. The result is that the proposed three-level model leads to the most conservative results.  相似文献   
997.
This paper examines the effects of an anticipated foreign military threat on consumption, the home weapons stock, and net foreign asset position in a small open economy. If the utility function is separable between butter and guns, the economy decreases both butter and guns when the news arrives, accumulates foreign assets prior to the foreign threat realization, and increases guns as the foreign threat realizes. If the utility function is nonseparable between butter and guns, the economy may have two dynamic responses. The first is similar to the separable case, except that consumption exhibits a discrete jump when the foreign threat realizes. The second is that the economy increases both butter and guns on impact, decumulates foreign assets prior to the foreign threat implementation, but either increases or decreases guns as the foreign threat realizes.  相似文献   
998.
Once a pricing kernel is established, bond prices and all other interest rate claims can be computed. Alternatively, the pricing kernel can be deduced from observed prices of bonds and selected interest rate claims. Examples of the former approach include the celebrated Cox, Ingersoll, and Ross (1985b) model and the more recent model of Constantinides (1992). Examples of the latter include the Black, Derman, and Toy (1990) model and the Heath, Jarrow, and Morton paradigm (1992) (hereafter HJM). In general, these latter models are not Markov. Fortunately, when suitable restrictions are imposed on the class of volatility structures of forward rates, then finite-state variable HJM models do emerge. This article provides a linkage between the finite-state variable HJM models, which use observables to induce a pricing kernel, and the alternative approach, which proceeds directly to price after a complete specification of a pricing kernel. Given such linkages, we are able to explicitly reveal the relationship between state-variable models, such as Cox, Ingersoll, and Ross, and the finite-state variable HJM models. In particular, our analysis identifies the unique map between the set of investor forecasts about future levels of the drift of the pricing kernel and the manner by which these forecasts are revised, to the shape of the term structure and its volatility. For an economy with square root innovations, the exact mapping is made transparent.  相似文献   
999.
The rapidly increasing volume of both published and unpublished work on the arbitrage pricing theory (APT) of Ross (1976) has given rise to a number of misunderstandings at the interface of theoretical and econometric work. In this article we extend the theoretical structure of our previous work (McElroy and Burmeister, 1985, 1988; Burmeister and McElroy, 1987, 1988) to provide a broad yet rigorous framework both for econometric estimation and for better economic interpretation of new empirical results. We begin with the case where allK factors are observed, and then present the second case ofK−1≡J observed APT factors and one unobserved factor, theresidual market factor introduced in McElroy and Burmeister (1985). The economic interpretations for equivalent specifications of this model are discussed, and we enumerate several immediate payoffs to these specifications. The main new results are concerned with the sometimes intricate relationships among APT models withK factors and APT models withK factors that are constrained to satisfy mean-variance efficiency restrictions. These results are not only of theoretical interest, but more importantly they provide the basis for econometric estimation and testing of nested hypotheses. These econometric issues are discussed in detail.  相似文献   
1000.
Polytomous logistic regression   总被引:1,自引:0,他引:1  
In this paper a review will be given of some methods available for modelling relationships between categorical response variables and explanatory variables. These methods are all classed under the name polytomous logistic regression (PLR). Models for PLR will be presented and compared; model parameters will be tested and estimated by weighted least squares and by likelihood. Usually, software is needed for computation, and available statistical software is reported.
An industrial problem is solved to some extent as an example to illustrate the use of PLR. The paper is concluded by a discussion on the various PLR-methods and some topics that need a further study are mentioned.  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