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181.
Edward P. Kahn Michael H. Rothkopf Joseph H. Eto Jean-Michel Nataf 《Journal of Regulatory Economics》1990,2(2):129-149
Competition was introduced into the electric utility industry with the passage of the Public Utilities Regulatory Policy Act (PURPA) of 1978. Increasing interest has appeared in structuring the PURPA purchase market into an auction system. This paper addresses the design issues associated with setting up such markets and introduces a simulation model to study them. The simulation analysis is guided by theoretical issues such as the alleged inefficiency of first-price auctions. We find that efficiency concerns raised about first-price auctions turn out to be less important than simple theoretical concerns would suggest. 相似文献
182.
Individual bid functions display sensitivity to the strategic considerations inherent in first-price auctions. However, several formal models, including heterogeneous Nash equilibrium bidding models with constant relative risk aversion, perform quite poorly. 相似文献
183.
H. Jerome Keisler 《Economic Theory》1995,5(1):127-173
Summary We introduce a probabilistic model for price adjustment in an exchange economy which approximates the classical Walras tâtonnement process while avoiding many of its unrealistic features. The model is decentralized in that the trades permitted to an agent and the resulting price changes depend only on the commodity vector currently held by that agent, and not on the commodity vectors held by the other agents in the economy. Our results will show that the Walras tâtonnement process can be decentralized without changing its behavior on the macroeconomic scale. Our model has a finite set of commodities, a market maker who adjusts prices, and a large finite set of agents who trade only with the market maker. Each agent has a demand function depending on his commodity vector and the price vector. At each discrete time, one agent is chosen at random and exchanges his current commodity vector for his demand vector. Then the market maker adjusts the price vector by an amount which depends on the selected agent's commodity vector and the current price. Prices are adjusted rapidly enough to avoid prolonged trading at the wrong price, but slowly enough so that a substantial price change will depend on a significant simple of agents. The main result shows that with probability arbitrarily close to one the price will rapidly approach and then remain close to an equilibrium value, following a path which is close to the price path of the corresponding tâtonnement process. 相似文献
184.
185.
Knut H. Alfsen Hugo Birkelund Morten Aaserud 《Environmental and Resource Economics》1995,5(2):165-189
Emission of CO2, SO2 and NOx are all closely linked to the burning of fossil fuels. Here we report on simulations done by linking a Sectoral European Energy Model (SEEM), covering energy demand in nine Western European countries, with the emission-transport-deposition model RAINS developed by IIASA. The study analyses emissions of CO2, SO2 and NOx, deposition of sulphur and nitrogen and the extent of areas where the critical load for sulphur is exceeded in year 2000 under four different energy scenarios. Two different sets of future behavioural patterns for the thermal electric power production sector are considered. In one regime, called the plan-efficient regime, the sector is assumed to follow official plans with regard to investment in new capacity. In the other regime, called the cost-efficient regime, the thermal power sector is assumed to behave in a cost minimizing manner. The effects of the proposed EC carbon/energy tax are studied under both regimes, giving rise to altogether four scenarios.In both regimes the effect of the EC tax is to reduce emissions by between 6 and 10 per cent in year 2000 relative to the scenarios without the tax. A change of regime, from the regulated, plan-efficient regime to the market-based, cost-efficient regime, will, by itself, reduce emissions of CO2 and NOx by approximately 3 per cent, while SO2 emissions are reduced by 13 per cent. The EC tax will reduce sulphur deposition by more than 5 per cent in the nine model countries under the plan-efficient regime. A change of regime further reduces the total deposition by 9 per cent. The area where depositions exceed the critical load is reduced by approximately 6 per cent in year 2000 by the tax in both regimes. Changing from the plan-efficient to the cost-efficient regime has a similar impact.Although the emission reductions due to the EC tax may seem modest, they are shown to have a sizeable effect on the technological abatement costs of reaching targets like those prescribed in the Sofia protocol on the stabilisation of NOx emissions, and the Helsinki protocol on SO2 emission reductions. This is part of what can be considered to be secondary benefits of the EC carbon/energy tax. 相似文献
186.
Hitting the Jackpot or Hitting the Skids: Entertainment, Poverty, and the Demand for State Lotteries
Garrick Blalock David R. Just Daniel H. Simon 《American journal of economics and sociology》2007,66(3):545-570
A bstract . State-sponsored lotteries are a lucrative source of revenue. Despite their low payout rates, lotteries are extremely popular, particularly among low-income citizens. State officials laud the benefits of lottery proceeds and promote the fun and excitement of participation. This entertainment value is one explanation for lottery demand by the poor: individuals with lower incomes substitute lottery play for other entertainment. Alternatively, low-income consumers may view lotteries as a convenient and otherwise rare opportunity for radically improving their standard of living. Bad times may cause desperation, and the desperate may turn to lotteries in an effort to escape hardship. This study tests these competing explanations. We examine lottery sales data from 39 states over 10 years and find a strong and positive relationship between sales and poverty rates. In contrast, we find no relationship between movie ticket sales, another inexpensive form of entertainment, and poverty rates. 相似文献
187.
H. Von Schneeberger 《Metrika》1973,20(1):1-16
Zusammenfassung Es wird gezeigt, daß sich das vonNeyman undTschuprow für ein einziges Merkmal gelöste Problem der optimalen Aufteilung des Stichprobenumfangs auf vorgegebene Schichten auf ein nichtlineares Programm mit linearen Restriktionen und nichtlinearer Zielfunktion zurückführen läßt. Auf Grund der Konvexitätseigenschaft der Zielfunktion ergibt sich, daß das Minimum der Zielfunktion (Minimum der Streuung des Stichprobenmittels
) stets eindeutig ist. Der beiNeyman undTschuprow mögliche Fall, daß sich in derh-ten Schicht ein Stichprobenumfang ergibt, der größer als der Umfang in der Gesamtheit ist, kann hier nicht auftreten.Durch Einführung einer verallgemeinerten Streuung wird das Problem der optimalen Aufteilung bei vorgegebener Schichtung imk-dimensionalen Merkmalsraum aufk Merkmale verallgemeinert. Es wird gezeigt, daß diese verallgemeinerte Streuung (=Zielfunktion eines nichtlinearen Programms) im allgemeinen nicht über dem ganzen konvexen Bereich der zulässigen Lösungen konvex (von unten) ist. Ein Teilbereich des zulässigen Bereichs, über dem die Zielfunktion konvex ist, wird angegeben. Schließlich werden hierzu vergleichende Ergebnisse gebracht. 相似文献
188.
Seven computerprograms for non-linear regression or curve fitting problems are compared. The comparison of the programs, running in different computing centra, is restricted to the fit performance. Six model functions are fitted according to the least squares criterion to data series, arising from practical work. The special least squares minimization programs turned out to be better suited for these problems than general optimizing programs. 相似文献
189.
This paper considers a stochastic frontier production function which has additive, heteroscedastic error structure. The model allows for negative or positive marginal production risks of inputs, as originally proposed by Just and Pope (1978). The technical efficiencies of individual firms in the sample are a function of the levels of the input variables in the stochastic frontier, in addition to the technical inefficiency effects. These are two features of the model which are not exhibited by the commonly used stochastic frontiers with multiplicative error structures.An empirical application is presented using cross-sectional data on Ethiopian peasant farmers. The null hypothesis of no technical inefficiencies of production among these farmers is accepted. Further, the flexible risk models do not fit the data on peasant farmers as well as the traditional stochastic frontier model with multiplicative error structure. 相似文献
190.
Aggregation bias, compositional change, and the border effect 总被引:2,自引:0,他引:2
Russell H. Hillberry 《The Canadian journal of economics》2002,35(3):517-530
Borders affect the composition, not only the level, of interregional trade. In disaggregated U.S. Commodity Flow data, border effects vary substantially across commodities. Substantial border–induced compositional change suggests the possibility that standard estimates suffer from aggregation bias arising from endogenous industry location patterns and the presence of zero observations in commodity–level trade. Adjusting for these effects reduces the estimate of the aggregate border effect from 20.9 to 5.7. JEL Classification: F14, F15
Biais d'agrégation, changement de composition, et effet de frontières. Les frontières affectent la composition et pas seulement le volume de commerce inter-régional. Une analyse des données désagrégées des flux de commerce de biens des Etats-Unis montre que l'effet de frontières varie substantiellement selon les biens. Le changement de composition du commerce engendré par les frontières suggère la possibilité que les estimations usuelles souffrent d'un biais d'agrégation résultant des patterns de localisation industrielle endogènes et de la présence d'observations nulles dans le commerce de certains biens. Un ajustement pour tenir compte de ces effets suggère que les effets de frontières passent de 20.9 à 5.7. 相似文献
Biais d'agrégation, changement de composition, et effet de frontières. Les frontières affectent la composition et pas seulement le volume de commerce inter-régional. Une analyse des données désagrégées des flux de commerce de biens des Etats-Unis montre que l'effet de frontières varie substantiellement selon les biens. Le changement de composition du commerce engendré par les frontières suggère la possibilité que les estimations usuelles souffrent d'un biais d'agrégation résultant des patterns de localisation industrielle endogènes et de la présence d'observations nulles dans le commerce de certains biens. Un ajustement pour tenir compte de ces effets suggère que les effets de frontières passent de 20.9 à 5.7. 相似文献