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51.
We propose two novel approaches for feature selection and ranking tasks based on simulated annealing (SA) and Walsh analysis, which use a support vector machine as an underlying classifier. These approaches are inspired by one of the key problems in the insurance sector: predicting the insolvency of a non‐life insurance company. This prediction is based on accounting ratios, which measure the health of the companies. The approaches proposed provide a set of ratios (the SA approach) and a ranking of the ratios (the Walsh analysis ranking) that would allow a decision about the financial state of each company studied. The proposed feature selection methods are applied to the prediction the insolvency of several Spanish non‐life insurance companies, yielding state‐of‐the‐art results in the tests performed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
52.
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   
53.
The Cuban economy has experienced a significant increase in foreign direct investment over the past decade due to the end of the Soviet Union and the establishment of more liberal trade policies. Although the U.S. embargo of trade with Cuba still exists, there has been movement lately that suggests the end of the four‐decades‐old policy. The purpose of this article is to analyze the current Cuban business environment and to identify potential entrepreneurial opportunities in the service sector. Major trade partners are also reviewed and managerial implications discussed. © 2006 Wiley Periodicals, Inc.  相似文献   
54.
介绍了重油悬浮床加氢裂化工艺的最新发展,对国内新开发的悬浮床加氢裂化工艺特点作了介绍。并将悬浮床加氢和三种重油轻质化工艺——固定床加氢、延迟焦化、重油催化裂化在技术经济上作了分析对比。在原油品质越来越差的今天,针对劣质重油而开发的的悬浮床加氢裂化工艺具有非常广阔的应用前景。  相似文献   
55.
作为中国金融业的一个重要组成部分,保险业处在对外开放的前沿,中国加入世界贸易组织为其所设定的过渡期已经结束,论文分析了过渡期以后中国保险业经营环境的变化趋势,并针对性地给出了对策建议。  相似文献   
56.
会计信息外部性的存在带来会计信息供求的冲突,解决此冲突的规则就是会计信息产权。会计信息产权需要界定才能发挥其应有的效能,会计信息产权的界定取决于对企业所有权分享、管制和道德等因素,企业所有权分享下的会计信息产权界定是初始的界定,无法完成初始界定时可采用管制方式进行强权界定,道德是会计信息产权界定不可缺少的因素。国企改革所滋生的各种问题的根源在于会计信息产权畸形性,欲抑制其畸形,正确处理国企所有权的分享问题的同时,建立“共同治理”的机制和“相机治理”机制是必不可少的。  相似文献   
57.
This study examines motivation and stock market reactions of firms announcing earnings in the Wall Street Journal (WSJ) after filing with the Security Exchange Commission (SEC). Most firms announce earnings in the WSJ before SEC filing. Firms that reverse this sequence are voluntarily delaying public earnings announcements. The authors find that these firms are not only poor financial performers but also engage in earnings managements. They are delaying their WSJ announcements to postpone announcing bad news. The authors find significant stock price reactions to both the SEC filing and the WSJ announcement. The price reaction to earnings is incomplete at the SEC filings. The market continues reacting to firms' subsequent WSJ announcements as if the SEC filing fails to communicate earnings information to some investors.  相似文献   
58.
We propose an optimal filter to transform the Conference Board Composite Leading Index (CLI) into recession probabilities in the US economy. We also analyse the CLI's accuracy at anticipating US output growth. We compare the predictive performance of linear, VAR extensions of smooth transition regression and switching regimes, probit, non‐parametric models and conclude that a combination of the switching regimes and non‐parametric forecasts is the best strategy at predicting both the NBER business cycle schedule and GDP growth. This confirms the usefulness of CLI, even in a real‐time analysis. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
59.
Public investment constitutes one of the main instruments of regional policies. The existence of a direct link between infrastructure and regional income per capita is usually accepted. Literature also describes a positive effect of public investment on private capital accumulation. This paper seeks to provide new empirical evidence on this latter relationship for the case of Spanish regions over the period 1965–1997 using panel data methodology. The results show a positive effect of productive and social public investment (especially in education) on private investment. The spillover effects generated by the productive infrastructures located in other regions do not seem to encourage the private investment in neighbouring regions. Public consumption and interest rate exert a negative influence on private capital accumulation. These results are robust to changes in the econometric specification.  相似文献   
60.
我国的国企改革走过了近三十年的风雨历程,如何建立行之有效的经营者激励制度一直是改革的热点问题.本文在全面阐述委托--代理理论的基础上,对我国国有企业经营者激励制度的演变进行分析,进而,就如何在委托--代理关系下的国有企业内建立有效的激励机制问题进行探讨.  相似文献   
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