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31.
This paper applies a stochastic frontier production model with time-varying technical efficiency to investigate the relationship between public capital and technical efficiency. It is based on the proposition that public capital has an effect on actual output by enhancing technical efficiency, thereby reducing the gap between maximum potential output and actual output. Empirical results using panel data from U.S. state manufacturing industries during 1969–86 show that technical efficiencies varied substantially, both between states and between years; variations in technical efficiency are significantly explained by variations in public-sector capital.
JEL Classification Numbers: O20, H54, C23.  相似文献   
32.
This article is a navigation guide to the twenty papers that emerged from the workshops conducted at the Sixth Invitational Choice Symposium (Estes Park, Colorado, June 2004). The papers are categorized into three broad sets that focus respectively on choice modeling issues, on providing interdisciplinary perspectives on choice, and on relating choice research to real world concerns. Within each category, we offer provide brief integrative overviews linking subsets of papers.  相似文献   
33.
文章论述了环境问题对人类的重要性及创造环保型的企业环境需要解决的问题,在此基础上,提 出了为实现环保型企业经营韩国政府所应该采用的政策及具体的实施方案。  相似文献   
34.
A feature transformation method based on domain knowledge for arti?cial neural networks (ANNs) is proposed. The method of feature transformation based on domain knowledge converts continuous values into discrete values in accordance with the knowledge of experts in speci?c application domains. This approach effectively ?lters data, trains the classi?er, and extracts the rules from the classi?er. In addition, it reduces the dimensionality of the feature space, which not only decreases the cost and time in the operation but also enhances the generalizability of the classi?er. The experimental results of the proposed approach will be compared and tested statistically with the results of the linear transformation method. The results show that the method of feature transformation based on domain knowledge outperforms the linear transformation in modelling of ANNs. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
35.
Contrary to the stereotype that the period between CEOs is a hiatus, interim and acting executives serve during an important strategic window. A model is presented to illustrate the dynamics of short-term leadership, including the precipitating circumstances for the temporary administration, the tasks of short-term leadership, and the moderating factors seen to affect the selection and success of the next chief executive. Researchers and practitioners are urged to consider more carefully the potential that a well-managed interregnum has to repair damage from a traumatic departure, buffer between administrations, and prepare the organization to accept and work with new leadership. © 1995 by John Wiley & Sons, Inc.  相似文献   
36.
In this paper, we discuss the properties of preliminary test estimators (PTE) of the parameters of simple linear model with measurement error (ME model) when the slope of the linear model is suspected to be zero. Expressions of the bias, MSE and efficiencies are obtained under conditional as well as unconditional situations with known reliability coefficient. Conditional model results are compared to the standard model without measurement error. We also provide the unconditional model analysis in finite samples. Asymptotic theory under local alternatives is developed when the variance of measurement error or the ratio of the variance of the model error relative to the variance of the measurement error is known. Asymptotic expressions of bias and MSE of the estimators along with their efficiencies are obtained. In every case, it is shown that the measurement error tend to increase the variability of the estimators compared to the estimators without measurement error. Graphs and tables are provided to see these results and to determine optimum level of significance for minimum guaranteed efficiency. Received October 2001 RID="*" ID="*"  A. K. Md. E. Saleh is a Distinguished Research Professor and H. M. Kim is a Ph.D. candidate in the School of Mathematics and Statistics, Carleton University, Ottawa. Acknowledgment. The authors gratefully acknowledge the constructive suggestion of the referees to improve the paper. The research is supported by NSERC grant A3088.  相似文献   
37.
Demand for product characteristics is examined within the context of models that allow for both corner and interior solutions corresponding to zero and non-zero demand. Product attribute information is associated with marginal utility and curvature (satiation) parameters of various utility functions. Empirical applications demonstrate the need for incorporating characteristics in a fairly general way. We also compare our approach to an ideal point and pure Lancasterian versions of our nonlinear utility model. The data support our model over either the ideal point or Lancasterian variants.  相似文献   
38.
In this study we propose a mathematical definition of the consumption efficiency of multi-attribute products in the price–quality space. A new model, the discrete Range Adjusted Measure (RAM) model, is suggested as an empirical tool to measure the level of consumption efficiency. We further discuss the effect of consumption efficiency on the innovation incentive. Empirical work is made for the mobile phone market. We expect that the consumption efficiency concept will contribute to the extension of the traditional framework of production efficiency analysis on the one hand and to the understanding of the nature of innovation in a technology-intensive market on the other hand.JEL Classification: C67, D11, D12, D21  相似文献   
39.
This paper applies Kim and Wardes (2004) stratified Warners randomized response model to Mangat and Singhs (1990) two-stage randomized response model. The proposed stratified randomized response model has an optimal allocation and a large gain in precision. Hence, the estimator based on the proposed method is more efficient than Kim and Wardes (2004) and Mangat and Singhs (1990) estimators under the conditions presented in both the case of completely truthful reporting and that of not completely truthful reporting by the respondents.  相似文献   
40.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

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