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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.
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   
34.
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   
35.
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   
36.
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   
37.
科技金融投入对产业结构优化升级具有重要影响作用。本文基于2011~2019年的省际面板数据,使用固定效应模型对中国30个省份进行实证分析,并使用工具变量解决内生性问题。研究结果表明,科技金融投入对产业结构的影响呈现"倒U型"的非线性特征;从作用机制来看,科技金融投入影响技术创新进而作用于产业结构升级;从地区上来看,科技金融投入对产业结构升级的影响在东部地区表现明显,中、西部地区作用不明显。据此,提出加快完善科技金融制度、完善多层次资本市场体系、注重高技术人才的培养、平衡地区发展等政策建议。  相似文献   
38.
T. Kim 《Economic Theory》1991,1(3):251-263
Summary A choice behavior of a decision maker is said to satisfy the subjective expected utility hypothesis if there exist a utility and a subjective probability such that a decision maker chooses acts with the highest expected utility. We present a revealed preference characterization of choice behavior that is consistent with the subjective expected utility hypothesis. Our result applies to any state space and compact sets of prizes and observations (either finite or infinite).  相似文献   
39.
This paper suggests an application of an averting behaviormethod to reconcile inconsistent public activity with objectiveenvironmental risk. In Korea, an historically polluted watersupply has created citizen resistance to using tap water. Koreansperceive low quality levels for tap water, although objectivelymeasured data show that the pollution levels are lower than theacceptable risk. We hypothesized that the irrational aversion tousing tap water is a consequence of inconsistencies between theobjectively measured and perceived pollution levels. We introducethe perception averting behavior method, in which we add aperception measure unit to the conventional averting behaviormethod. We found that the perception measure provided a validexplanation for citizens' aversion to using tap water in Korea.  相似文献   
40.
移动WiMAX与WiBro之间的关系WiBro源自韩国。早在2004年7月韩国信息通讯部(MIC)正式公布移动WiMAX(WiBro)的服务要求之前,韩国电信技术协会(TTA)内部就开展了一项本地  相似文献   
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