Consumer preferences before and after a food safety scare: An experimental analysis of the 2010 egg recall

In August 2010, more than half a billion eggs were recalled in the U.S. because of a Salmonella outbreak. This study examines the effect of the recall with a unique pair of auction experiments investigating willingness to pay (WTP) for conventional and organic eggs, one conducted shortly before and one right after the recall with the same participants. In addition to the before and after bids, participants bid again after a negative information or balanced information treatment about the event. Accompanying surveys showed consumers had a high level of awareness of the recall but less knowledge of specific details, and viewed information on egg farm conditions as very important in their WTP. While there were no significant before and after differences, WTP for organic eggs significantly increased in the negative information treatment, and balanced information had a positive effect on consumer WTP for conventional eggs.     

基于零售商开通网络渠道的多渠道供应链定价策略

文针对拥有网络直销渠道的制造商，考虑零售商实体渠道促销努力水平及消费者的搭便车行为，在 Nash博弈和零售商主导的Stackelberg 博弈下，就零售商开通网络渠道的问题进行研究。通过理论和数值分析，得到以下结论：零售商渠道地位对其开通网络渠道影响不大；开通后，制造商利润减小，当实体渠道基本市场份额较小时，零售商利润增大；零售商应根据实体渠道基本市场份额大小来决定是否开通网络渠道。     

Maximizing benefits in project selection: a hybrid approach

Charitable foundations and government programmes should endeavour to allocate their limited resources to best serve their constituents. Yet, mathematical programming techniques are rarely used despite overwhelming evidence of their superiority in selecting projects that yield higher levels of total benefits. We present a novel ‘hybrid selection model’ that combines binary linear programming and heuristic rank-based models applied to two case studies. The first case focuses on providing services to women and shows a hybrid model would have selected the top three ‘signature’ projects and maintained an above-average overall project benefit while securing a 180% improvement in the number of projects funded, a 66% improvement in the number of women served and a 132% improvement in the total benefit achieved. In the second case, we apply the hybrid approach to data from the US government’s largest forest preservation programme and demonstrate that the hybrid approach could allow the programme to select up to 11 top-scoring projects while still achieving a 97% gain in the total overall benefit compared to their traditional method. These case studies show that the hybrid approach has the potential to be applied in a variety of settings and improve how foundations and programmes achieve their goals.     

Achievements and gaps in tef productivity improvement practices in the marginal areas of Northern Ethiopia: implications for future research directions

Tef is the most important crop in Ethiopia and is well-adapted to growing environments, but grain yields are low. The government is therefore promoting the adoption of improved varieties, inorganic fertilizers and new planting techniques. This study gathered information on the use of new agronomic practices and barriers to their adoption through a semi-structured questionnaire administered to 60 farmers or respondents from each of 4 districts of Tigray region in northern Ethiopia viz Laelay-Maichew, Medebay-Zana, Ahferom and Alamata. Data were coded and analysed using SPSS software. Except for animal feed and crop rotation, there were significant differences between districts in the relative importance of several criteria for different uses. Improved varieties were used by the majority of respondents in all districts and fertilizers in all except Alamata where severe moisture stress dictated the choice of variety and reduced fertilizer application. Weed control was mainly by hand except in Alamata where chemical control was common because of the predominance of broad-leaved weeds. Transplanting maximized the yield of tef, but a cost–benefit analysis showed that row sowing was more profitable. The study concluded that new varieties better adapted to the likelihood of reduced rainfall and that respond efficiently to fertilizer inputs need to be developed. Until suitable technologies are available, high labour costs would in part dictate some agronomic practices, even if this led to lower yields.     

Internal Migration of Blacks in South Africa: An Application of the Roy Model

This study investigates the internal migration of black males in South Africa over the period after the formal end of Apartheid using the 1996 census data. The two issues of our primary interests are the following: (i) whether migration patterns of black individuals are consistent with the income‐maximising hypothesis as related to the destination choice; and (ii) whether the redistribution of human capital is detected in internal migration. The results from conditional logit regressions on choices among individuals in 318 districts show that individuals prefer districts with higher expected wages, conditional on other regional characteristics. In addition, there exist differing preferences on the share of population with post‐secondary education by individuals with commensurate educational attainments. Black individuals with post‐secondary education tend to migrate into areas with a higher share of population with post‐secondary education and vice versa, which confirms the divergence of human capital levels across districts.     

A novel decision support model for satisfactory restaurants utilizing social information: A case study of TripAdvisor.com

Decision support models for satisfactory restaurants have attracted numerous researchers' attention. Many extant models do not consider the active, neutral and passive information in online reviews all at once. Moreover, they ignore the effect of interdependence among criteria on tourists' decision-making. To cover these defects, this study proposes a restaurant decision support model using social information for tourists on TripAdvisor.com. The model introduces fuzzy sets to denote online reviews and utilizes Bonferroni mean to consider interdependence among criteria. Furthermore, it uses a novel similarity measurement which can handle sparse data in fuzzy environments. To validate the model, we conduct a case study of TripAdvisor.com which compares the proposed model with four other models. The performance of each model is evaluated by the metric called the mean absolute error. The study shows that the proposed model can effectively support tourists' decision-making and it performs better than the other four models.     

Impossibilities for strategy-proof committee selection mechanisms with vetoers

When a group of voters selects a committee out of a set of candidates, it is common and often desirable to endow these voters with some veto power. I present impossibility results showing that even limited veto power makes many mechanisms of interest manipulable. This applies in particular (i) to mechanisms the range of which contains a degenerate lottery in which a committee is chosen for sure and (ii) to mechanisms that are constructed from extensive game forms with a finite number of strategies. These impossibilities hold on a large set of domains including the domain of additive preferences, and even when probabilistic mechanisms are allowed and voters can report cardinal preferences.     

Agricultural landowners⿿ response to incentives for afforestation

Previous research has shown that afforestation of agricultural land is a relatively low-cost option compared to energy-based approaches for mitigating net carbon dioxide emissions, and that financial incentives affect landowner behavior and can be used to increase carbon sequestration on private land. In this paper we use stated preference data from private landowners in the Pacific Northwest region of the U.S. to examine the key factors affecting participation in an incentive program for carbon sequestration through afforestation. We also estimate the corresponding potential for carbon sequestration and its cost. Our results suggest that incentive payments would significantly and positively affect landowners⿿ level of enrollment in a tree planting program.     

Demand for ecolabeled seafood in the Japanese market: A conjoint analysis of the impact of information and interaction with other labels

The use of seafood ecolabels is expanding in the world marketplace, but so are labels indicating other product attributes, such as country of origin and wild vs. farmed. The interactive effects of these labels and attributes in evaluating consumers’ preferences for ecolabeled seafood are relatively unexplored. In this paper we investigate (1) the direct and interactive effects of seafood ecolabels with other common fish labels, and (2) how consumers’ perceptions about the state of marine stocks and the valuation of ecolabels may be affected by different information. We find moderate interactive effects between ecolabels and country of origin labels, whereas the valuation for seafood ecolabels is fairly high. In terms of information, we find that consumers’ perceptions about fish stock levels changed (negatively) after receiving information on declining stock levels, and more sensationalized information led to increased change. However, valuation for a seafood ecolabel increases only when the information was perceived positively (credible/interesting); whereas exaggerated information (which was also perceived less credible) had insignificant effects on WTP.     

Supplier selection and partnerships: Effects upon restaurant operational and strategic benefits and performance

This study focused on identifying strategic criteria involved in selecting suppliers of restaurant products/services specific to casual dining, full service independent restaurants to obtain operational and strategic benefits for those managers operating in this highly competitive marketplace. A total of 765 responses were obtained from managers at independently owned restaurants throughout the U.S. Results revealed that ‘product’ and ‘financial/technical’ criteria had significant and positive effects upon operational benefits, while ‘product’ and ‘service’ had positive effects upon strategic benefits. When the sample was segmented into low and high supplier partnership groups, the positive effects of ‘financial/technical’ and ‘cost/price’ were significantly greater for the ‘high’ partnership group pertaining to operational benefits. ‘Product’ and ‘service’ and their effects upon strategic benefits were greatest for the high partnership group. Based on our findings, implications, limitations, and recommendations for future studies have been provided.