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During qualitative research on trust, conducted in a mariculture chain in southern Brazil, the theme of informality emerged spontaneously in most interviews. Although it is difficult to measure, some data and estimates point out that informality is still quite present worldwide, but especially in emerging and developing countries, and this situation was confirmed in the studied supply chain. In analysing the narratives, we noticed that this is a chronic issue which bothers the producers that are properly formalised mainly because of unfair competition, and hinders the organisation of the chain. Some factors foster the persistence of informality, such as family labour and temporary jobs, the low educational level of entrepreneurs, lack of adequate supervision and cultural aspects of producers and their families. We could corroborate the perspectives of modernisation (informality is still persistent), neo-liberal (informal entrepreneurs reject the bureaucracy of an over-regulated market) and post-structuralist (informality is a way of life related to identity, social position and/or resistance against the formal structure) theories. Our research has shown us that the situation found is contributing to a reduction in the number of formal producers and impairing the development of that local supply chain, as well as its sustainability.  相似文献   
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Abstract:  Current research suggests that the large downside risk in hedge fund returns disqualifies the variance as an appropriate risk measure. For example, one can easily construct portfolios with nonlinear pay-offs that have both a high Sharpe ratio and a high downside risk. This paper examines the consequences of shortfall-based risk measures in the context of portfolio optimization. In contrast to popular belief, we show that negative skewness for optimal mean-shortfall portfolios can be much greater than for mean-variance portfolios. Using empirical hedge fund return data we show that the optimal mean-shortfall portfolio substantially reduces the probability of small shortfalls at the expense of an increased extreme crash probability. We explain this by proving analytically under what conditions short-put payoffs are optimal for a mean-shortfall investor. Finally, we show that quadratic shortfall or semivariance is less prone to these problems. This suggests that the precise choice of the downside risk measure is highly relevant for optimal portfolio construction under loss averse preferences.  相似文献   
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The possible contribution of local sales chains to the reduction of energy consumption has been hotly debated in recent years. Some authors establish a link between the reduction of distances traveled by food and lower energy consumption due to transportation, while others hold that local supply chains have a poor energy performance. This article engages this debate by comparing the rates of energy consumption attributable to different modes of distribution of fruits and vegetables in a region of France.  相似文献   
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Although the core of most services is a person-to-person encounter, we still know very little about its underlying mechanisms as very few models or theories have been developed for these dynamic interactions between persons. An holistic approach to quality improvement is therefore suggested. Different prototypical person-to-person encounters may be studied on different levels and interfaces in service operations to eliminate inconsistencies. The aim of this contribution is to review some recent research findings for person-to-person encounters from the neighbouring management fields of services, operations and human resources in order to draw together their strategic implications for service managers. Some ontological and methodological considerations of studying person-to-person encounters from a qualitative perspective are discussed. The outline of a multi-disciplinary and learning-centred research approach is also suggested. Findings are integrated by a model of four generic and strategic processes for quality improvement in service operations. Finally, some implications for managers are proposed.  相似文献   
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The 1990s have witnessed several financial crises, of whichthe East Asia and Mexico tequila crises are perhaps the mostwell known. What impact have these crises had on labor markets,household incomes, and poverty? Total employment fell by muchless than production declines and even increased in some cases.However, these aggregates mask considerable churning in employmentacross sectors, employment status, and location. Economies thatexperienced the sharpest currency depreciations suffered thedeepest cuts in real wages, though deeper cuts in real wagesrelative to GDP were associated with smaller rises in unemployment.To some extent, families smoothed their incomes through increasedlabor force participation and private transfers, though thelimited evidence available suggests that wealthier familieswere better able to smooth consumption. The initial impact ofthe crises was on the urban corporate sector, but rural householdswere affected as well and in some instances suffered deeperlosses than did urban families. School enrollment declined,especially among poorer families, as did use of health facilities,but he impact on children's nutrition levels appears to vary.Crises have typically proved short-lived, but whether householdsplunged into poverty during a crisis are able to recover asthe economy does remains an open question.   相似文献   
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