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51.
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   
52.
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   
53.
On the Role of Weight Restrictions in Data Envelopment Analysis   总被引:3,自引:3,他引:0  
This paper examines the role that weight restrictions play in Data Envelopment Analysis (DEA). It is argued that the decision to include a factor (input or output) in a DEA model represents an implicit judgement that the factor has a non-trivial weight. It therefore seems perverse to allow DEA to assign a trivial weight to that factor in assessing the efficiency of a unit. There is therefore a strong case for imposing restrictions on factor weights. However, many existing methods of weight restriction are in practice unwieldy. This paper proposes an alternative approach we term contingent weight restriction which is both practical and intellectually consistent with the DEA philosophy. The paper explores the implications of alternative methods of weight restriction using simulated data from a well known production process.  相似文献   
54.
In the process of coding open-ended questions, the evaluation of interjudge reliability is a critical issue. In this paper, using real data, the behavior of three coefficients of reliability among coders, Cohen’s K, Krippendorff’s α and Perreault and Leigh’s I r are patterned, in terms of the number of judges involved and the categories of answer defined. The outcome underlines the importance of both variables in the valuations of interjudge reliability, as well as the higher adequacy of Perreault and Leigh’s I r and Krippendorff’s α for marketing and opinion research.  相似文献   
55.
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   
56.
In this paper, we analyze a majority voting process on the earnings-related part of pension benefits in a Social Security system with flexible retirement. We show that the aging of the population may make it easier to implement one of the proposed reforms to achieve a delay in the average retirement age of workers, to reinforce the link between contributions and pensions.  相似文献   
57.
Synopsis It has been difficult to make progress in the study of ethnicity and nationalism because of the multiple confusions of analytic and lay terms, and the sheer lack of terminological standardization (often even within the same article). This makes a conceptual cleaning-up unavoidable, and it is especially salutary to attempt it now that more economists are becoming interested in the effects of identity on behavior, so that they may begin with the best conceptual tools possible. My approach to these questions has been informed by anthropological and evolutionary-psychological questions. I will focus primarily on the terms ‘ethnic group’, ‘nation’, and ‘nationalism’, and I will make the following points: (1) so-called ‘ethnic groups’ are collections of people with a common cultural identity, plus an ideology of membership by descent and normative endogamy; (2) the ‘group’ in ‘ethnic group’ is a misleading misnomer—these are not ‘groups’ but categories, so I propose to call them ‘ethnies’; (3) ‘nationalism’ mostly refers to the recent ideology that ethnies—cultural communities with a self-conscious ideology of self-sufficient reproduction—be made politically sovereign; (4) it is very confusing to use ‘nationalism’ also to stand for ‘loyalty to a multi-ethnic state’ because this is the exact opposite; (5) a ‘nation’ truly exists only in a politician’s imagination, so analysts should not pretend that establishing whether something ‘really’ is or is not ‘a nation’ matters; (6) a big analytic cost is paid every time an ‘ethnie’ is called a ‘nation’ because this mobilizes the intuition that nationalism is indispensable to ethnic organization (not true), which thereby confuses the very historical process—namely, the recent historical emergence of nationalism—that must be explained; (7) another analytical cost is paid when scholars pretend that ethnicity is a form of kinship—it is not.  相似文献   
58.
This paper shows how the interaction between decentralized information gathering and discreteness of investment decisions at the individual level can generate random fluctuations in aggregate investment that involve occasionally large allocation errors. This interaction is illustrated in a model in which private information is costly to acquire and prices reveal information. The unique rational expectations equilibrium outcome of the model is shown to always be noisy and characterized by investment levels which may be high simply because uninformed investors are buying under the impression that the high price is a signal of good investment opportunities.  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.
This paper shows how the interaction between conflict and growth can give rise to a nonmonotone relationship between property rights and social welfare. This interaction is illustrated in a model of endogenous growth in which equilibrium diversion of resources is the cost of securing effective property rights. A symmetric equilibrium allocation associated with more secure property rights and faster growth can be Pareto dominated by one associated with poorer property rights and slower growth. Faster growth can exacerbate the problem of diversion whenever property rights are sufficiently poor. These results call for caution before a society decides to pursue economic growth independently of the institutional structure of property rights. Furthermore, if this structure is inappropriate piecemeal reform might not be in the interest of society, and a substantial reform might be necessary if it is to be welfare-improving.  相似文献   
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