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121.
In multi-armed bandit problems, information acquired from experimentation is valuable because it tells the agent whether to select a particular option again in the future. This article tests whether people undervalue this information because they are ambiguity averse, or have a distaste for uncertainty about the average quality of each alternative. It is shown that ambiguity averse agents have lower than optimal Gittins indexes, appearing to undervalue information from experimentation, but are willing to pay more than ambiguity neutral agents to learn the true mean of the payoff distribution, appearing to overvalue objectively given information. This prediction is tested with a laboratory experiment that elicits a Gittins index and a willingness to pay on six two-armed bandits. Consistent with the predictions of ambiguity aversion, the Gittins indexes are significantly lower than optimal and willingnesses to pay are significantly higher than optimal.  相似文献   
122.
Quality of life (QoL) is being considered as one of the fundamental concepts in contemporary era. It tries to assess the level of general welfare of the communities. Urban transitional neighborhoods possess specific situation and as a result present distinctive QoL. The major objective of this study is to identify and measure the QoL dimensions in urban transitional neighborhoods using both objective and subjective indices pertaining to Darvazeshemiran neighborhood of Tehran. In order to accomplish this and gather needed data, 244 questionnaires were distributed among Darvazeshemiran’s residents. This study suggests that there exists low level of QoL in the study area. That is 64.3 % of the residents were dissatisfied with the prevailing level of QoL. This in turn is associated with the transitional nature of this neighborhood. The residents were strongly dissatisfied with regard to the environmental qualification as opposed to accessibility status. Furthermore, this study identified five objective factors respectively regarding QoL. There exists low correlation between subjective and objective dimensions. That demands simultaneous consideration of both objective and subjective dimensions. It is argued that individual treatments of each could not accurately represent the QoL of residents.  相似文献   
123.
This paper draws on a survey design to investigate whether family ownership and leadership have an influence on the decision-facilitating and decision-influencing roles of management control. Moreover, we investigate whether the more intuitive decision making in family firms which is often said to be caused by a lack of professionalism, is indeed a disadvantage. The results indicate significant differences in the use of management controls between family firms and non-family firms. However, in contrast to the prevailing view in literature, the performance of family firms is not affected negatively by their specific way of making decisions and by their more centralized management style. According to our data, the prevailing characterization of family firms as being less professionally managed seems questionable.  相似文献   
124.
Many European countries during the 1990s and early 2000s tried to raise labor market flexibility by relaxing their employment protection legislation. This paper investigates whether the reforms have influenced job and employment stability for labor market entrants in Germany and Italy. Duration models are estimated using comparable administrative data for the two countries. The results provide, to some extent, evidence of a decrease in job stability. However, this is not accompanied by a compensating increase in employment stability during the first 3 years after labor market entry.  相似文献   
125.
This paper examines the goals of organizations that sponsor short-term volunteer trips in global health, whether they be NGO’s, faith-based, educational, or corporate organizations. Results from a U.S.-based national survey of 177 such organizations and 27 interviews with trip organizers suggest that organizations often sponsor volunteer trips to achieve goals that are quite different from the improvement of health outcomes in poor countries. While providing health services is often cited as the most important goal, volunteer activity is also considered important in enhancing the organizations’ reputation, recruitment and retention, and financial well-being. The prominence of other goals has the potential for diverting resources and focus from what is presumably the primary purpose of serving host communities in the most effective manner possible.  相似文献   
126.
In response to water quality standard violations linked to excessive organic matter (OM) and a lack of sampling data informing the Total Maximum Daily Load (TMDL), an organic matter budget was created to quantify and identify sources of OM in the lower Jordan River (Salt Lake City, UT). By sampling dissolved, fine and coarse particulate OM, as well as measuring ecosystem metabolism at seven different sites, the researchers aimed to identify the origin of excess OM, and understand pathways by which different size classes of the OM pool are generated. The dissolved fraction (DOM; 94 %) was found to be the dominant form of OM transported within the river with fine particulate organic matter (FPOM; 6 %) the second most abundant, and coarse particulate organic matter (CPOM; 1 %) transport relatively insignificant in the overall OM budget. Primary production exceeded respiratory losses in the upper river, and this, along with OM inputs from two tributaries (where water reclamation facilities discharge into the river) delivered excess OM to the impaired lower reaches. Increasing stream metabolism index (SMI) with distance downstream (>1 in the lower river) further demonstrated that transport of excessive organic matter into the lower river was from upstream sources and not due to lateral inputs. This simple approach to characterizing the organic matter budget as it relates to water quality in the Jordan River was effective and could serve as a model for future studies attempting to quantify and identify sources of OM in urban ecosystems.  相似文献   
127.
We treat robust M-estimators for independent and identically distributed Poisson data. We introduce modified Tukey M-estimators with bias correction and compare them to M-estimators based on the Huber function as well as to weighted likelihood and other estimators by simulation in case of clean data and data with outliers. In particular, we investigate the problem of combining robustness and high efficiencies at small Poisson means caused by the strong asymmetry of such Poisson distributions and propose a further estimator based on adaptive trimming. The advantages of the constructed estimators are illustrated by an application to smoothing count data with a time varying mean and level shifts.  相似文献   
128.
This report on practice discusses the pertinence of agile principles on the basis of the case “Universitätskolleg”, a central organisational unit of Universität Hamburg to promote the quality of studies and teaching. It describes previous experience with the framework scrum and the method Lean Kanban in mind. Odds and challenges of agile principles in university context are described and reflected and next steps are named.  相似文献   
129.
130.
Before the fall of the Berlin Wall, mortality was considerably higher in the former East Germany than in West Germany. The gap narrowed rapidly after German reunification. The convergence was particularly strong for women, to the point that Eastern women aged 50–69 now have lower mortality despite lower incomes and worse overall living conditions. Prior research has shown that lower smoking rates among East German female cohorts born in the 1940s and 1950s were a major contributor to this crossover. However, after 1990, smoking behavior changed dramatically, with higher smoking intensity observed among women in the eastern part of Germany. We forecast the impact of this changing smoking behavior on East-West mortality differences and find that the higher smoking rates among younger East German cohorts will reverse their contemporary mortality advantage. Mortality forecasting methods that do not account for smoking would, perhaps misleadingly, forecast a growing mortality advantage for East German women. Experience from other countries shows that smoking can be effectively reduced by strict anti-smoking policies. Instead, East Germany is becoming an example warning of the consequences of weakening anti-smoking policies and changing behavioral norms.  相似文献   
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