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61.
Are celebrity endorsements worthwhile investments in advertising? To answer this question, we analyze a unique sample of 101 announcements made between 1996 and 2008 by firms listed in the USA. Internet is the main medium of communication for these announcements. We employ event study methodology and document statistically insignificant abnormal returns around the announcement dates. This finding is consistent with the notion that the incremental benefits from celebrity endorsements closely match the incremental costs due to such contracts. Further, we investigate if the announcement date return depends on a number of characteristics that are often used in the endorsement literature. As a result, we find that endorsements of technology industry products coincide with significant positive abnormal returns around the announcement dates. Finally, we find weak support for the match-up hypothesis between celebrities and endorsed products.  相似文献   
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Estimating the cost of liquidity in agricultural futures markets is challenging because bid‐ask spreads are usually not observed. Based on an ability to reflect simulated data from Roll's spread model, we assess the effectiveness of conventional and Bayesian bid‐ask spread estimators under different market conditions. Conventional serial covariance and absolute price change spread estimators appear to be biased. Hasbrouck's Bayesian estimator generates small costs of liquidity whose values depend on the correlation and noise in the data. The absolute value Bayesian estimator is precise and works well under conditions of high levels of noise and correlation usually found in agricultural futures markets. Using data from live cattle (LC) and lean hog (LH) contracts, we find similar patterns of performance that produce economically meaningful cost of liquidity differences.  相似文献   
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A major component of the United States Environmental Protection Agency's 112(r) Risk Management Program Rule is the evaluation and control of potential public exposures to toxic chemicals. The rule requires identification and evaluation of a worst case accidental toxic release scenario, but provides for the inclusion of passive mitigation systems in modeling the dispersion hazard zones that are to be communicated to the public. These passive mitigation systems can be taken into account in the consequence modeling if they will withstand the initiating event that causes the accidental release and function as intended. This paper discusses several passive mitigation systems that can be designed as an integral part of storage or processing of highly toxic chemicals. These include, but are not limited to, optimizing storage conditions, design of secondary containment, toxic vapor generation control, and enclosure design. The effectiveness of various passive mitigation systems is evaluated using consequence modeling for case studies involving highly toxic chemicals such as phosgene, chlorine, and ethylene oxide.  相似文献   
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Sustainable technology development implies large changes in technological systems. The illustrative process ‘hydrogen fuel cell in a boat’ is used here as an example of a learning process concerning a transition towards a hydrogen economy. Theoretically the concepts of constructive technology assessment, back-casting and social niche management are combined in this approach.  相似文献   
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We investigate the impact of direct payments on agricultural commercialisation in Kosovo. Kosovo is one of the poorest countries in Europe but, with European assistance, provides substantial funds to support agriculture, made up of many small and often semi‐subsistence farms. Thus, the effect of this support is a central policy issue. Identifying the effect of direct payments on market participation faces endogeneity issues arising from the possible simultaneous determination of participation in support programmes and market participation. In order to achieve proper identification of the endogenous direct payments, we use a strategy of targeted identification search that employs several different methodological approaches. We find that direct payments for fruit and vegetables, and those for cereals and oilseeds have a positive effect on market participation. However, we cannot identify any definite effect of livestock payments.  相似文献   
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The sustainable livelihoods (SL) approach offers a holistic framework and a practical toolkit to analyze tourism's impacts and interactions within a community. This study argues that the usefulness of the SL approach in tourism can be enhanced by ensuring that the approach is built on a genuine people-centered starting point. The exploration of the local community's representations of, and aspirations for, their roles in tourism as a future livelihood choice meets this need. To verify the value of this approach empirically, this study examined the case of Lhasa, Tibet, and local youth as the research respondents. The findings suggest that the young hosts in Lhasa urban area were heterogeneous in their responses to tourism as a future livelihood choice. They fell into four subgroups: in-betweeners, ambivalent supporters, alternative supporters, and lovers. Further, this study examined the profiles of these four subgroups and explored their responses. The study enhances the SL approach by taking tourism as an example and clearly defining the departure point for its adoption within the context of broader livelihoods portfolios. Additionally, it suggests some potential directions for tailored management strategies to meet youth and community perspectives.  相似文献   
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