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951.
International policy now constantly advocates a need for populations to engage in more physical activity to promote health and to reduce society’s health care costs. Such policy has developed guidelines on recommended levels and intensity of physical activity and implicitly equates health with well-being. It is assumed that individual, and hence social welfare will be enhanced if the activity guidelines are met. This paper challenges that claim and raises questions for public policy priorities. Using an instrumental variable analysis to value the well-being from active leisure, it is shown that the well-being experienced from active leisure that is not of a recommended intensity to generate health benefits, perhaps due to its social, recreational or fun purpose, has a higher value of well-being than active leisure that does meet the guidelines. This suggests rethinking the motivation and foundation of existing policy and perhaps a realignment of priorities towards activity that has a greater contribution to social welfare through its intrinsic fun and possibly social interaction. 相似文献
952.
953.
We examine the theoretical properties of the auction for Medicare Durable Medical Equipment. Two unique features of the Medicare auction are (1) winners are paid the median winning bid and (2) bids are nonbinding. We show that median pricing results in allocation inefficiencies as some high‐cost firms potentially displace low‐cost firms as winners. Further, the auction may leave demand unfulfilled as some winners refuse to supply because the price is set below their cost. We also introduce a model of nonbinding bids that establishes the rationality of a lowball bid strategy employed by many bidders in the actual Medicare auctions and recently replicated in Caltech experiments. We contrast the median‐price auction with the standard clearing‐price auction where each firm bids true costs as a dominant strategy, resulting in competitive equilibrium prices and full efficiency. (JEL D44, I11, H57) 相似文献
954.
When are identity dilemmas—when people possess identities that conflict with one another and both are potentially stigmatizing—most likely to occur? Are they the result of generic social processes? A review of some of the extant research on “identity work” suggests that historical “misalignments” of culture and stratification, which we refer to as “lag,” create the greatest potential for stigma and the reproduction of inequalities. Lag is exacerbated by complex, intersecting axes of hierarchy, and amplified as symbolic environments globalize and subcultures multiply. Articulating culture and structure reveals how power plays out in interaction, and highlights the omnipresence of struggles for treatment as “fully human.” We consider whether “alignment” is even possible when multiple dimensions of social location intertwine, compete, and collide. Following Schwalbe and Mason‐Schrock (1996), we argue that “subcultural” or collective identity work that brings new meanings into dominant cultural narratives may offer the greatest hope, but in the interim all coping strategies are costly. 相似文献
955.
Peter Kotzian 《International Review of Sociology》2015,25(2):262-280
A capitalist market economy is based on several institutional elements, such as private ownership and competition. Does public support for this economic model rise if the economy prospers, and fall during a downturn? Or is public support largely independent of the ups and downs of economic cycles? We hypothesize that positive economic performance increases support and that persons profiting personally are more supportive of the economic system's constitutive institutional elements. Using multilevel regression we study the determinants of individual-level support for the economic system. We also test for differences in the perception of economic performance due to political attitudes and personal properties. The findings partly support the hypotheses, indicating that macro-economic factors matter for individual-level attitudes towards the economy. Attitudes towards different institutional elements of the economic system also differ in the degree to which they are political or economic, and influenced by economic performance. Individual features – education and personal economic stakes – affect attitudes towards the economy, but a substantial share of the individual-level variation in economic attitudes remains unexplained. 相似文献
956.
We estimate a mixed logit model of the demand for local news service. Results provide evidence that suggest the representative consumer values more diverse news, more coverage of multicultural issues, and more information on community news, and has a distaste for advertising. Demand estimates are used to calculate the impact on consumer welfare from a marginal decrease in the number of independent television stations that lowers the amount of diversity, multiculturalism, community news, and advertising. Consumer welfare decreases, but the losses are smaller in large markets. For example, small‐market consumers lose $45 million annually while large‐market consumers lose $13 million. (JEL C9, C25, L13, L82, L96) 相似文献
957.
Diversification gains in mean-variance efficiency derived from including real estate in financial asset portfolios are examined. Optimal financial and mixed-asset portfolios were generated by selecting from an investment universe including several distinct financial and real estate media. Deficiencies of previous studies were overcome by employing data with improved representativeness and comparability. The efficient mixed-asset portfolios dominated the efficient financial asset portfolios implying that purely financial asset diversification is inefficient. The optimal mixed-asset portfolio prescribed that approximately two-thirds of the investment wealth be allocated to real estate and one-third to the financial media. 相似文献
958.
Roger J. Gagnon 《决策科学》1988,19(2):453-471
Teaching an operations design course has major pedagogical challenges. (1) The design topics—output, process, facility, and work design—are necessarily taught sequentially, yet the decisions are integrative. (2) Instruction must be generic to service or product producers. (3) Discussing output design is difficult since students typically have had no exposure to the “product language” of engineering graphics. (4) No text is available which examines in sufficient depth all the operations design decisions. (5) Cases necessarily depict historical situations—process technologies and economic data—while operations managers must plan future directions for their productive systems. (6) While the commercial world contains fresh information and data, students are inexperienced in obtaining knowledge from the real world. (7) While the course presents an operations management perspective, students must recognize the information, data, and cooperation necessary from the other functional areas to successfully complete the operations design. To help overcome these seven pedagogical challenges, the students in the undergraduate and graduate operation design courses complete a comprehensive feasibility study for a new product or service and the entire productive system. 相似文献
959.
This paper addresses the problem of open order rescheduling in a job shop. Results are reported of experiments conducted in a simulation model of an 8-machine job shop. Four different order updating policies are examined. The due-date process is modeled to include several realistic features about the pattern of due-date variability. These features are parameterized and tested at several levels. Tardiness results indicate that open order rescheduling is beneficial only when allowances are loosely set. The results indicate that inventory performance is improved by order rescheduling, particularly in cases when due dates are revised to earlier times than originally forecast. 相似文献
960.
Growing human populations make it imperative for ecologists to identify strategies to conserve biodiversity in human-dominated landscapes, such as cities. Effects of urbanization on birds are particularly well-studied, but questions remain regarding the best conservation approaches. Debate about the relative utility of focusing conservation efforts on nature reserves versus developed lands has focused largely on comparing species abundance or presence, with few studies addressing underlying behavioral or demographic mechanisms. Here we evaluated differences in avian reproductive success in nature reserves and matrix habitats to test the assumption that nest predation is lower within areas protected from development. Specifically, we investigated 1) whether nest survival differed in replicated pairs of forest parks and residential neighborhoods and 2) whether differences in nest survival were associated with changes in which species most frequently depredated nests. From April–August 2007–2014, we monitored nests of two native birds, American robin (Turdus migratorius) and northern cardinal (Cardinalis cardinalis), and video-documented nest predators in paired forest-matrix habitats in the Columbus, Ohio metropolitan area. We found similar rates of nest survival in the two habitats for both robins (Χ21?=?0.715, p?=?0.398, n?=?741 nests) and cardinals (Χ21?=?0.926, p?=?0.336, n?=?1156 nests), but interactions between predators and prey differed. In particular, domestic cats (Felis catus) were over five times as likely to depredate cardinal nests in matrix habitats versus forest parks (Χ21?=?7.24, simulated p?=?0.010; nforest?=?3, nmatrix?=?7). Our results suggest that at least in some circumstances, nest success of native birds may be equivalent between nature reserves and adjacent residential matrix habitats, and thus residential neighborhoods may contribute positively to bird conservation in urban landscapes. 相似文献