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91.
In this paper we investigate the use of the structured full rank model for hedging the balance sheet of a financial institution. Simulation results suggest that the optimal hedge is insensitive to changes in parameter estimates. In addition, we hedge a portfolio of Treasury bills using both the full information covariance matrix and the structured covariance matrix. We then contrast these results with those obtained from a duration-based model. Empirical results suggest that the structured full rank model is generally more effective in hedging applications than either the full information model or duration-based model.  相似文献   
92.
The maritime industry provides an interesting case study of the design and implementation of drug-testing programs in the transportation industry during the 1980s. It is clear that such programs were designed and implemented less because of empirical evidence of safety problems than for political reasons. The results in the maritime industry are indicative of a program that is expensive to operate, intrusive with regard to employee privacy, and which will have little or no impact on safety. Focusing such programs on the issue of impairment rather than on the issue of drug usage per se is likely to improve the outcome of the programs. Although, despite common belief, there is little evidence that drug usage or the “drug problem” in U.S. society as a whole had gotten worse in the preceding years (Schonsheck, 1989, 250–251).  相似文献   
93.
Too often companies fall into a trap when developing a list of performance specifications for a new product. Milton Rosenau calls this the best-of-the-best specification trap. The problem arises whenever a company bases a specification on the combination of the best single features observed in available competitive products. When this happens, the new product's design is driven by competition and is not derived from a unique market insight. This may not provide the basis for a sustainable advantage. Sometimes, rumors of competitive improvements may even lead to sudden changes in the specification, creating delays in the development process. A far better goal is to develop a specification that responds to an unrecognized and unfilled user need, one that adds high value to users. His points are illustrated with several examples.  相似文献   
94.
During the past decade a number of countries imposed capital controls that had two distinguishing features: they were asymmetric, in that they were designed principally to discourage capital inflows, and they were temporary. This paper studies formally the consequences of these policies, calibrates their potential effectiveness, and assesses their welfare implications in an environment in which the level of capital inflows can be sub-optimal. In addition, motivated by the fact that these types of controls have often been left in place after the dissipation of the shock that lead to the controls being implemented, the paper evaluates the welfare cost of procrastination in removing these types of controls.  相似文献   
95.
Teaching New Product Development To Employed Adults   总被引:1,自引:0,他引:1  
The purpose of this article is to report the lessons derived from broad practical experience in teaching new product development (NPD) to employed adults. My observations are importantly augmented by diverse comments from nine other service providers who also conduct and participate in similar NPD education. Our combined lessons summarize what works and what to be forewarned about. (“Those who cannot remember the past are condemned to repeat it.”– George Santayana.) We believe that what we have learned from our very different and extensive involvement can help several audiences: (1) others who offer or plan to offer and deliver NPD education – educators, service providers, or practitioners; (2) organizations that may wish to sponsor NPD training in any form; and (3) those who expect to participate as students in NPD seminars or courses. The article has four main sections, all of which are intended to provide pointers and helpful suggestions based on our collective experience. First is a discussion of issues concerning program set‐up and acceptance. Both sponsors and participants have important responsibilities for this, which are explained. Second is a discussion of practical issues specific to NPD education. The varieties of subject matter and support materials, format options, techniques to sustain interest, instructor characteristics, and client confidentiality are covered. Third is a discussion of practical logistic issues that apply to all adult education but with an emphasis on NPD. Advance warning of what can be and has been encountered may help you circumvent many avoidable problems. Fourth is a brief discussion about the future for NPD education. In this we speculate that the emergence of broadband Internet may provide a new modality, the effectiveness of which is still uncertain. An important insight for you to note is that we do not always do the same thing or approach teaching situations in the same way. What has worked for one of us may not have been effective for another or in another situation. In summary, the experiences we record should help you improve the delivery of NPD education or more efficiently benefit from participation in such training. © 2002 Elsevier Science Inc. All rights reserved.  相似文献   
96.
97.
Predicting the geo-temporal variations of crime and disorder   总被引:2,自引:0,他引:2  
Traditional police boundaries—precincts, patrol districts, etc.—often fail to reflect the true distribution of criminal activity and thus do little to assist in the optimal allocation of police resources. This paper introduces methods for crime incident forecasting by focusing upon geographical areas of concern that transcend traditional policing boundaries. The computerised procedure utilises a geographical crime incidence-scanning algorithm to identify clusters with relatively high levels of crime (hot spots). These clusters provide sufficient data for training artificial neural networks (ANNs) capable of modelling trends within them. The approach to ANN specification and estimation is enhanced by application of a novel and noteworthy approach, the Gamma test (GT).  相似文献   
98.
This article matches establishment-level data on workplace transformation (e.g., quality circles, work teams, and just-in-time production) with measures of cumulative trauma disorders at these same establishments to explore the relationship between "flexible" workplace practices and workplace health and safety. The results reveal a positive, statistically significant, and quantitatively sizable relationship between cumulative trauma disorders and the use of quality circles and just-in-time production.  相似文献   
99.
In-depth data analysis plus statistical modeling can produce inferentialcausal models. Their creation thus combines aspects of analysis by close inspection,that is, reason analysis and cross-tabular analysis, with statistical analysis procedures,especially those that are special cases of the generalized linear model (McCullaghand Nelder, 1989; Agresti, 1996; Lindsey, 1997). This paper explores some of the roots of this combined method and suggests some new directions. An exercise clarifies some limitations of classic reason analysis by showing how the cross tabulation of variables with controls for test factors may produce better inferences. Then, given the cross tabulation of several variables, by explicating Coleman effect parameters, logistic regressions, and Poisson log-linear models, it shows how generalized linear models provide appropriate measures of effects and tests of statistical significance. Finally, to address a weakness of reason analysis, a case-control design is proposed and an example is developed.  相似文献   
100.
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