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241.
In this paper, we evaluate the economic cost of the Islamic State on the Syrian and Iraqi economies from 2010 to 2016. To do so, we use the Post-Terrorism Final Economic Damage Simulator—PTFED-Simulator. The PTFED-Simulator assesses the economic damage of terrorism based on ten different indicators: (1) total regional terrorism tension (?Tt); (2) harmonized anti-terrorist strategy (AT+); (3) war losses from terrorism (?πt); (4) total economic leakage from terrorism (?Ψt); (5) economic desgrowth from terrorism (?δt); (6) military dimension of terrorism (MDt); (7) post-terrorism economic damage (?Πt); (8) post terrorism economic damage evaluation; (9) post-terrorism reconstruction plan (PTRt); and (10) terrorism effect on mega-disk networks mapping. Overall, we seek to evaluate the impact of terrorism on economic performance from a multi-dimensional perspective in both the short run and long run.  相似文献   
242.
Multivariate GARCH (MGARCH) models need to be restricted so that their estimation is feasible in large systems and so that the covariance stationarity and positive definiteness of conditional covariance matrices are guaranteed. This paper analyzes the limitations of some of the popular restricted parametric MGARCH models that are often used to represent the dynamics observed in real systems of financial returns. These limitations are illustrated using simulated data generated by general VECH models of different dimensions in which volatilities and correlations are interrelated. We show that the restrictions imposed by the BEKK model are very unrealistic, generating potentially misleading forecasts of conditional correlations. On the other hand, models based on the DCC specification provide appropriate forecasts. Alternative estimators of the parameters are important in order to simplify the computations, and do not have implications for the estimates of conditional correlations. The implications of the restrictions imposed by the different specifications of MGARCH models considered are illustrated by forecasting the volatilities and correlations of a five-dimensional system of exchange rate returns.  相似文献   
243.
The present paper studies various criteria used by upscale restaurant owners to differentiate their restaurants and to define their positioning. In particular, we studied several wine list attributes. Through a cluster analysis and a correspondence factor analysis based on different objective wine list characteristics, we obtain two main differentiated profiles of restaurants according to the relative importance of their wine list in comparison with food menu: wine selection and complementarity. Upscale restaurants need to define their positioning strategy and elaborate their wine lists according to their strategy.  相似文献   
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In this paper, an approach for reorganizing Web sites based on user access patterns is proposed. Our goal is to build adaptive Web sites by evolving site structure to facilitate user access. The approach consists of three steps: preprocessing, page classification, and site reorganization. In preprocessing, pages on a Web site are processed to create an internal representation of the site. Page access information of its users is extracted from the Web server log. In page classification, the Web pages on the site are classified into two categories, index pages and content pages, based on the page access information. After the pages are classified, in site reorganization, the Web site is examined to find better ways to organize and arrange the pages on the site. An algorithm for reorganizing Web sites has been developed. Our experiments on a large real data set show that the approach is efficient and practical for adaptive Web sites. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
247.
In the mid 1980s there was a remarkable revival of interest in growth theory. A relevant strand of new literature is characterized by the departure from the assumption of diminishing returns of capital or, more generally, of the accumulated factor. In this paper we will see how the neoclassical theorists incorporated the idea of increasing returns in the formal models of economic growth, already an important question in the sixties. The central point is that the recent recognition of the importance of this notion is not new but now depends on the vision of economic growth as driven by knowledge accumulation and no longer by capital accumulation as in the Solovian tradition. I would like to thank the referee for valuable comments and suggestions.  相似文献   
248.
Nella prima parte di questo lavoro, definita l'indipendenza tra gli attributi di una funzione di utilità di due variabiliu(x, y) si determinano forme multilineari del tipou(x, y) = 1 u 1 (x) + 2 u 2 (y) + 12 u 1 (x)u 2 (y) e se ne studiano le proprietà.Successivamente si propongono alcune approssimazioni diu(x, y) e si verifica quali proprietà fondamentali degli ordinamenti di preferenza esse conservano. In entrambi i casi si ottengono delle forme la cui utilità acquista rilevanza nella semplificazione operativa nei problemi di decisione in condizioni di incertezza.
Here we propose two different methods to overcome the pratical difficulties present in the application of two-attribute utility functions in decision problems under uncertainty. The first method consists in deriving them through modified preference axioms, whereas the second deals with their numerical approximations without violating the fundamental properties of preference ordering.


Lavoro eseguito nell'ambito del C.N.R.-G.N.A.F.A.  相似文献   
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