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141.
We consider a dynamic pricing problem that involves selling a given inventory of a single product over a short, two‐period selling season. There is insufficient time to replenish inventory during this season, hence sales are made entirely from inventory. The demand for the product is a stochastic, nonincreasing function of price. We assume interval uncertainty for demand, that is, knowledge of upper and lower bounds but not a probability distribution, with no correlation between the two periods. We minimize the maximum total regret over the two periods that results from the pricing decisions. We consider a dynamic model where the decision maker chooses the price for each period contingent on the remaining inventory at the beginning of the period, and a static model where the decision maker chooses the prices for both periods at the beginning of the first period. Both models can be solved by a polynomial time algorithm that solves systems of linear inequalities. Our computational study demonstrates that the prices generated by both our models are insensitive to errors in estimating the demand intervals. Our dynamic model outperforms our static model and two classical approaches that do not use demand probability distributions, when evaluated by maximum regret, average relative regret, variability, and risk measures. Further, our dynamic model generates a total expected revenue which closely approximates that of a maximum expected revenue approach which requires demand probability distributions.  相似文献   
142.
Despite documented benefits of remanufacturing, many manufacturers have yet to embrace the idea of tapping into remanufactured‐goods markets. In this article, we explore this dichotomy and analyze the effect of remanufacturable product design on market segmentation and product and trade‐in prices by studying a two‐stage profit‐maximization problem in which a price‐setting manufacturer can choose whether or not to open a remanufactured‐goods market for its product. Our results suggest that it is optimal for a manufacturer to design a remanufacturable product when the value‐added from remanufacturing is relatively high but product durability is relatively low and innovation is nominal. In addition, we find that entering a remanufactured‐goods market in and of itself does not necessarily translate into environmental friendliness. On the one hand, the optimal trade‐in program could result in low return and/or remanufacturing rates. On the other hand, a low price for remanufactured products could attract higher demand and thereby potentially result in more damage to the environment. Meanwhile, external restrictions imposed on total greenhouse gas emissions draw criticism in their own right because they risk stifling growth or reducing overall consumer welfare. Given these trade‐offs, we therefore develop and compare several measures of environmental efficiency and conclude that emissions per revenue can serve as the best proxy for emissions as a metric for measuring overall environmental stewardship.  相似文献   
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144.
Components of nursing home (NH) culture change include resident-centeredness, empowerment, and home likeness, but practices reflective of these components may be found in both traditional and “culture change” NHs. We use mixed methods to examine the presence of culture change practices in the context of an NH’s payer sources. Qualitative data show how higher pay from Medicare versus Medicaid influences implementation of select culture change practices, and quantitative data show NHs with higher proportions of Medicare residents have significantly higher (measured) environmental culture change implementation. Findings indicate that heightened coordination of Medicare and Medicaid could influence NH implementation of reform practices.  相似文献   
145.
Research has shown that family income's relations to early childhood achievement is stronger in large inner cities and weaker in less urbanized areas. Research has not yet considered whether links between family income and achievement in adolescence differ across the urban to rural landscape. Using nationally representative data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998–1999 (N ≈ 9,350), this study examines differences in family income's links with eighth‐grade achievement across large urban, small urban, suburban, and rural communities. The point at which income‐achievement links plateau occurs later in the income distribution in less urbanized areas. The magnitude of the association between family income and reading and science skills also differs across the urban‐rural continuum, such that family income has stronger relations to reading and science achievement in urban cities and weaker links in suburban and rural communities.  相似文献   
146.
This small-scale research explores the generation of social capital in young people growing up in one urban area and one rural area in Scotland via community-led youth work projects that aim to re-engage young people categorised as NEET (Not in Employment Education or Training). By looking at their varied and complex biographies, it considers young people's experiences and perceptions of their communities and their transitions from education to the workplace. Using social capital as a theoretical lens, we examined the impact that youth work can have not just on these important transitions but also upon the young people themselves. By visiting two different sites of engagement we were able to explore whether the type of initiative (media or sports) or place (urban or rural) had an impact on the generation of capital for young people. The youth work practice in both areas acted as a glue between the young people and their communities, creating opportunities where the two could be bound together and relationships created. This occurred in both sites regardless of the area or type of initiative and confirmed in this study that youth work acts as a site of capital building.  相似文献   
147.
While the new epistemology and related models of therapy are claimed to have radical social implications, the Milan approach is in ill repute amongst feminists who see it as conservative in relation to women's issues. This paper explores the sociopolitical implications of the new epistemology and the Milan approach, concluding that, while second order cybernetics has greater potential to incorporate a radical social analysis, it has, nevertheless, failed to do so. The application of second order cybernetics in family therapy appears to be constrained by the sociopolitical conservatism of its proponents.  相似文献   
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149.
In a majority rule voting game, the uncovered set is the set of alternatives each of which can defeat every other alternative in the space either directly or indirectly at one remove. Research has suggested that outcomes under most reasonable agenda processes (both sincere and sophisticated) will be confined to the uncovered set. Most research on the uncovered set has been done in the context of voting games with a finite number of alternatives and relatively little is known about the properties of the uncovered set in spatial voting games.We examine the geometry of the uncovered set in spatial voting games and the geometry of two important subsets of the uncovered set, the Banks set and the Schattschneider set. In particular, we find both general upper and lower limits on the size of the uncovered set, and we give the exact bounds of the uncovered set for situations with three voters. For situations with three voters, we show that the Banks set is identical to the uncovered set.  相似文献   
150.
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