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31.
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   
32.
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   
33.
The aim of this article is to investigate differences between the British public and private sectors in terms of the decentralisation of employment relations. Drawing on data from the 1998 Workplace Employee Relations Survey, the article arrives at three main conclusions. First, the analysis reveals that while local‐level managers in both sectors have similar levels of responsibility for employment relations issues, those in the public sector are, on the whole, significantly less likely to be able to exercise authority. Second, the results indicate some marked variations in practice within the public sector, with managers in education having the greatest level of authority. Finally, the article explores the extent to which differences in local‐level authority between the public and private sectors can be explained by higher‐level collective bargaining, and the presence of higher‐level personnel specialists. These factors have only a partial influence, and do not fully explain why local‐level employee relations managers in some areas (notably health) are less able to exercise authority than their counterparts in the private sector.  相似文献   
34.
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   
35.
The purpose of this paper is to analyze strategic behavior of vertically integrated firms when there is downstream entry, taking into account the balance between competition in the market and competition for the market. This analysis can serve to explain diverse distributional structures, including the coexistence of vertically integrated firms and independent retailers. And it shows that the relative efficiency of downstream entrants and the level of competition among incumbents are two major factors in determining equilibrium configuration.  相似文献   
36.
本文认为,韩国新村运动对中国农村发展有着重要的启示:一是要鼓励村民积极参与到农村发展项目的执行中来;二是村庄之间为了获取发展项目应展开竞争;三是项目管理中要允许适当的分权行为;四是要认识到非经济激励的重要性;五是应发挥村级中介组织的作用.  相似文献   
37.
This study investigates price relationships between organic and conventional carrots, tomatoes, and lettuce in the U.S. utilizing Nielsen scanner data from 2006–2015. We employ a threshold vector error correction model (TVECM), threshold vector autoregressive model (TVAR), and threshold cointegration test to test whether market integration exists between organic and conventional vegetables as well as the existence of asymmetric price transmission. The results find positive long-run relationships between organic and conventional prices of carrots and tomatoes and show the existence of asymmetric price transmission in price pairs of lettuce and tomatoes. Our findings suggest that the price relationship between organic and conventional vegetables varies by characteristics, such as shelf life, volatility in the price premium, and substitutability.  相似文献   
38.
We examine the long-run return performance of over 1,600 firms with reverse stock splits. These stocks record statistically significant negative abnormal returns over the three-year period following the month of the reverse split. The sample firms experience poor operating performances over the four years that include and follow the year of the reverse split, which suggests informational inefficiencies. Because these stocks have unique financial characteristics, we also show that they would be very difficult to sell short. Thus, arbitrageurs would be restricted in their ability to earn abnormal profits, even if they correctly anticipated a price decline.  相似文献   
39.
Traditional U.S. industries with higher firm-specific stock return and fundamentals performance heterogeneity use information technology (IT) more intensively and post faster productivity growth in the late 20th century. We argue that this mechanically reflects a wave of Schumpeter's creative destruction disrupting a wide swath of industries, with successful IT adopters unpredictably undermining established firms. This validates endogenous growth theory models of creative destruction and suggests intensified creative destruction as explaining findings associating greater firm-specific performance variation with higher per capita GDPs, economy growth rates, accounting standards, financial system development, and property right protection.  相似文献   
40.
We propose a new approach for investigating the performance of managed funds using wavelet analysis and apply it to an Australian dataset. This method, applied to a multihorizon Sharpe ratio, shows that the wavelet variance at the short scale is higher than that of the longer scale, implying that an investor with a short investment horizon has to respond to every fluctuation in the realized returns, while for an investor with a much longer horizon, the long-run risk associated with unknown expected returns is not as important as the short-run risk. Using multihorizon Sharpe ratios of six groups of managed funds, we find that none of the fund groups are dominant over all time scales.
Robert Faff (Corresponding author)Email:
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