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991.
Ersin Ancel Ann T. Shih Sharon M. Jones Mary S. Reveley James T. Luxhøj Joni K. Evans 《Journal of Risk Research》2013,16(4):428-451
This paper illustrates the development of an object-oriented Bayesian network (OOBN) to integrate the safety risks contributing to an in-flight loss-of-control aviation accident. With the creation of a probabilistic model, inferences about changes to the states of the accident shaping or causal factors can be drawn quantitatively. These predictive safety inferences derive from qualitative reasoning to conclusions based on data, assumptions, and/or premises, and enable an analyst to identify the most prominent causal factors leading to a risk factor prioritization. Such an approach facilitates a mitigation portfolio study and assessment. The model also facilitates the computation of sensitivity values based on perturbations to the estimates in the conditional probability tables. Such computations lead to identifying the most sensitive causal factors with respect to an accident probability. This approach may lead to vulnerability discovery of emerging causal factors for which mitigations do not yet exist that then informs possible future R&D efforts. To illustrate the benefits of an OOBN in a large and complex aviation accident model, the in-flight loss-of-control accident framework model is presented. 相似文献
992.
We propose a new methodology for discrete time dynamic hedging with transaction costs that has three key performance features. First, the methodology can accommodate the use of a wide range of objective functions, from the use of many types of utility functions to the more traditional objectives of hedging error minimization. Second, our methodology can significantly outperform traditional dynamic hedging methodologies across a range of objective functions. Third, our methodology can be applied to both single and multi-dimensional options while analytical methods typically can only be applied to single dimensional options. 相似文献
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We use a least squares metric to match the return pattern of a target stock with that of an out‐of‐sample‐twin. The twin with the smallest metric is found by a comprehensive period‐by‐period search of stocks in the Center for Research in Security Prices data set extending back to 1926. If technical analysis has value, targets of twins producing the highest returns in the twin postperiod should also have the highest performance in the target postperiod. Using a randomly selected sample of 66,000 return patterns, we find higher means for targets corresponding to the highest returning twin quintile. We also use regressions to risk adjust target returns and find that twin returns in the postmatch period significantly predict risk‐adjusted target returns. 相似文献
996.
James A. Chyz Winnie Siu Ching Leung Oliver Zhen Li Oliver Meng Rui 《Journal of Financial Economics》2013
We examine the impact of unionization on firms' tax aggressiveness. We find a negative association between firms' tax aggressiveness and union power and a decrease in tax aggressiveness after labor union election wins. This relation is consistent with labor unions influencing managers' in one, or both, of two ways: (1) constraining managers' ability to invest in tax aggressiveness through increased monitoring; or (2) decreasing returns to tax aggressiveness that arise from unions' rent seeking behavior. We also find preliminary evidence that the market expects these reductions around union elections and discounts firms that likely add shareholder value via aggressive tax strategies. 相似文献
997.
Existing research on chief executive officer (CEO) turnover focuses on CEO ability. This paper argues that board ability is also important. Corporate boards are reluctant to replace CEOs, as this makes financing expensive by sending a negative signal about board ability. Entrenchment in this model does not result from CEO power, or from agency problems. Entrenchment is mitigated when there are more assets-in-place relative to investment opportunities. The paper also compares public and private equity. Private ownership eliminates CEO entrenchment, but market signals improve investment decisions. Finally, the model implies that board choice in publicly listed firms will be conservative. 相似文献
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This study applies linear and nonlinear Granger causality tests to examine the dynamic relation between London Metal Exchange (LME) cash prices and three possible predictors. The analysis uses matched quarterly inventory, UK Treasury bill interest rates, futures prices and cash prices for the commodity lead traded on the LME. The effects of cointegration on both linear and nonlinear Granger causality tests is also examined. When cointegration is not modelled, evidence is found of both linear and nonlinear causality between cash prices and analysed predictor variables. However, after controlling for cointegration, evidence of significant nonlinear causality is no longer found. These results contribute to the empirical literature on commodity price forecasting by highlighting the relationship between cointegration and detectable linear and nonlinear causality. The importance of interest rate and inventory as well as futures price in forecasting cash prices is also illustrated. Failure to detect significant nonlinearity after controlling for cointegration may also go some way to explaining the reason for the disappointing forecasting performances of many nonlinear models in the general finance literature. It may be that the variables are correct, but the functional form is overly complex and a standard VAR or VECM may often apply. 相似文献
1000.
This paper examines and compares the technical efficiency measures of Ontario and New York dairy producers for the period 1992 to 1998. A nonparametric stochastic frontier model is introduced to estimate technical efficiency. The backfitting algorithm of Breiman and Friedman is used to estimate the frontier. Empirical results indicate that during the period of study, New York dairy farmers produced milk more efficiently than Ontario dairy producers, but the magnitude of the difference was small. The estimated mean technical efficiency for the former group is 0.602 as compared to 0.532 for the latter. The results also indicated that over time, dairy farms in both regions improved their level of technical efficiency. Furthermore, no correlation was found between farm size and estimated technical efficiency. 相似文献