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61.
Since the regional scale turns out to be the scale at which fiscal devolution is likely to be accomplished in Italy, and that at which trade and growth interdependencies as well as regional convergence can be most conveniently investigated, a new 20-region input–output model for Italy seems to be a useful tool of analysis. Although various regional and interregional models have been constructed since the 1950s, none has been implemented for the whole system of 20 Italian administrative regions considered in their tight mutual dependence; also, the pool approach has not been greatly favoured, even in situations where direct information on regional trade is lacking. The main purpose of this paper is to report on the structure of the model, the rather complex procedure used in the model construction and the adopted solution technique. Some space is devoted to the problems encountered in handling regional trade endogenously in an input–output setting and to a comparison between the pool approach, used in the Italian model, and other current techniques. The paper also reports on some preliminary results regarding the regional impact of fiscal policy.  相似文献   
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The profound financial crisis generated by the collapse of Lehman Brothers and the European sovereign debt crisis in 2011 have caused negative values of government bond yields both in the USA and in the EURO area. This paper investigates whether the use of models which allow for negative interest rates can improve option pricing and implied volatility forecasting. This is done with special attention to foreign exchange and index options. To this end, we carried out an empirical analysis on the prices of call and put options on the US S&P 500 index and Eurodollar futures using a generalization of the Heston model in the stochastic interest rate framework. Specifically, the dynamics of the option’s underlying asset is described by two factors: a stochastic variance and a stochastic interest rate. The volatility is not allowed to be negative, but the interest rate is. Explicit formulas for the transition probability density function and moments are derived. These formulas are used to estimate the model parameters efficiently. Three empirical analyses are illustrated. The first two show that the use of models which allow for negative interest rates can efficiently reproduce implied volatility and forecast option prices (i.e. S&P index and foreign exchange options). The last studies how the US three-month government bond yield affects the US S&P 500 index.  相似文献   
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Of 1,211 farmers and their representatives registered on www.accessagriculture.org, 142 participated in an on-line survey in November 2017, designed to learn farmer’s opinions of Access Agriculture, an NGO which hosts a digital platform where anyone can watch or download videos and other information for free. These farmer learning videos all convey practical information on sustainable agricultural innovations, to encourage farmer experiments. Previous experience showed that smallholders liked having their own copy of videos (e.g. on DVD), but this study showed that farmers are now starting to find their own way to the internet to pro-actively search for information. Although some farmers learn about on-line videos by social contacts, most of the farmers found the videos on www.accessagriculture.org by surfing the web. This suggests that limitations of reaching farmers with traditional forms of video distribution (e.g. DVDs and village screenings) will be partly overcome by the Internet. Youth have become the new information brokers for communities, as elders may lack the digital technology skills needed to use the Internet to get agricultural information. To share videos with other community members, youth will benefit from additional tools, such as an app, to allow easy download and sharing with limited data consumption.  相似文献   
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ABSTRACT

Based on the existing marketing concept on relational and functional benefits and on the retailing management of customer value, the present research empirically tests the influence of these customer benefits by providing a comparative analysis for different retailing formats, such as supermarkets and hypermarkets. Using questionnaire data for a sample of customers (N = 362), the authors developed structural equation modeling. This study identifies the factors influencing customer value, as well as the key to understand the relationships of customer benefits, customer value, loyalty, and purchase intention in the retailing service context. The contribution of the present research includes empirically testing a conceptual model, by developing a comparative analysis, along with providing some meaningful insights to retailing managers on how to strategically manage customer value variables to increase and enhance customer retention and purchase intent.  相似文献   
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More diverse, perennial cropping systems often have better natural mechanisms for keeping pests at bay. But while scientists emphasise the broad benefits of conservation in terms of effective ecosystem functioning, farmers are more interested in biodiversity for the provision of food or of services such as shade or windbreaks. Because of their limited knowledge of the role of biodiversity in plant protection, farmers sometimes unconsciously disturb natural regulatory mechanisms. Some citrus farmers in Vietnam introduced sapodilla as an intercrop to diversify their source of income, and because this fruit tree requires little care. However, this apparently worthwhile attempt to combine two valuable crops has misfired. The ecological conditions that traditionally sustained natural pest control in citrus have been disturbed, thus trapping farmers in the pesticide treadmill. The weaver ant Oecophylla smaragdina stopped protecting citrus from stinkbugs and leaf-feeding caterpillars after facing competition from the black ant Dolichoderus thoracicus, which favours sapodilla trees as a nesting habitat. To avoid similar scenarios in the future, methods for linking scientific research on ecosystem functions with farmers' own knowledge, experience and priorities are presented. Examples are given of ways in which farmers in perennial cropping systems learn, and how scientists can facilitate this learning process.  相似文献   
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This article empirically investigated the invariance and discriminant validity of a six-factor leadership model across two very divergent cultures: the United States and Turkey. In conjunction with the rationalist approach to international management, it was hypothesized that the same range of six leadership styles would appear in both cultures. However, coinciding with the culturalist approach to international management, it was also hypothesized that managers would emphasize different styles in each culture. Turkish and US managers each completed the Leadership Effectiveness Questionnaire measuring degree of emphasis placed on six leadership styles. Results of the test of model invariance indicated that the six styles existed in both cultures; however, discriminant analysis demonstrated that the Autocratic and Consensus styles differentiated managers best. Turkish managers emphasized the Autocratic style to a greater extent and the Consensus style to a lesser extent than did US managers. Implications for international management are discussed. ©1998 John Wiley & Sons, Inc.  相似文献   
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This paper provides further evidence of price and volume effects associated with index compositional changes by analysing the inclusions (exclusions) from the French CAC40 and SBF120 indices, as well as the FTSE100. I find evidence supporting the price pressure hypothesis associated with index fund rebalancing, but weak or no evidence for the imperfect substitution, liquidity and information hypotheses. The results improve on recent evidence from the S&P500 index. The evidence for the FTSE100 additions shows, in particular, that markets learn about an imminent inclusion and incorporate this information into prices, even before the announcement date.  相似文献   
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