Evaluating Wisconsin dairy producer compliance and potential eligibility for international markets under existing European Union and United States Grade “A” bulk tank somatic cell count compliance criteria

A proposal to lower the bulk tank Somatic Cell Count (SCC) maximum for United States of America (US) Grade “A” milk producers was not adopted by the National Conference on Interstate Milk Shipments in 2011 or 2013. The proposal would have made the US Grade “A” limit consistent with many other international standards, including that of the European Union (EU). Some US states, however, have proactively adopted their own SCC limit to mirror the EU limit. The purpose of this study was to analyze the impacts on Wisconsin dairy producers if Wisconsin should adopt the current EU limit and compliance criterion. Analyses were done on SCC results for Wisconsin Grade “A” and Grade “B” dairy producers reported each month to the Wisconsin Department of Agriculture, Trade and Consumer Protection (WDATCP) during January 1, 2009–December 31, 2012. Results were evaluated against the current US Grade “A” and EU compliance criteria for SCC and the percentage of (producer × month) combinations in compliance was determined. If the current EU SCC compliance criterion was in place, 86.7–94.3 and 64.3–77.3% of Wisconsin Grade “A” and “Grade “B” (producer × month) combinations, respectively, would have been in compliance for the years 2009–2012. Compliance of Wisconsin Grade “A” and Grade “B” producers with the existing US SCC compliance criterion during the same period was 99.3–99.7% and 87.9–93.9% (producer × month combinations) respectively. An analysis of a subset of Wisconsin Grade “A” producers indicated that smaller-volume producers were less likely than larger-volume producers to meet the EU criterion.     

A count data model with endogenous household specific censoring: the number of nights to stay

In this paper a count data regression model accounting for endogenous censoring with household specific censoring thresholds is presented. The presented modelling approach is utilized in an analysis of household choice of total number of nights to spend on monthly recreational trips. The empirical study reveals that the suggested approach is feasible and that accounting for endogenous censoring gives a better fit to the data. For helpful comments on an earlier version of the paper we thank two anonymous referees.     

国标法测定即食紫菜菌落总数结果的不确定度评定及其应用

文章通过对即食紫菜菌落总数检验结果的不确定度评定,介绍了食品菌落总数不确定度的评估方法及其应用,并对检验结果在限量标准附近的合格评定进行了讨论。     

湖南省南县土地利用动态变化研究

土地利用变化是区域变化的重要组成部分,是短时期内人类活动对自然环境改造的显著表现形式.随着人口持续增长和社会经济的快速发展,南县土地利用发生了较大变化.以土地统计资料为依据,对南县1983-2003年的土地利用变化过程进行了全面分析.结果表明:土地利用结构发生了明显变化;土地利用变化速度较快;土地利用程度较高,土地利用处于调整期;人类活动对景观格局有较为明显的影响.     

Structural drivers of upstream supply chain complexity and the frequency of supply chain disruptions

A great deal of research has focused on supply chain risk management, but the question “Which supply chain characteristics increase the frequency of supply chain disruptions?” has not received much attention from empirical research. This is a relevant question, because firms seek stability in their operations, and therefore managers need to know how the structure of their supply chains affects the occurrence of disruptions. The present study addresses this issue with a specific focus on upstream supply chain (supply-side) disruptions. Drawing on the literature on supply chain complexity, we devise and test a model that predicts the frequency of supply chain disruptions based on a multi-dimensional conceptualization of upstream supply chain complexity. Not only do the empirical findings suggest that all of the three investigated complexity drivers – horizontal, vertical, and spatial complexity – increase the frequency of disruptions, but also that they interact and amplify each other's effects in a synergistic fashion.     

Asymmetric effects of online consumer reviews

Consumers tend to seek heuristic information cues to simplify the amount of information involved in tourist decisions. Accordingly, star ratings in online reviews are a critical heuristic element of the perceived evaluation of online consumer information. The objective of this article is to assess the effect of review ratings on usefulness and enjoyment. The empirical application is carried out on a sample of 5,090 reviews of 45 restaurants in London and New York. The results show that people perceive extreme ratings (positive or negative) as more useful and enjoyable than moderate ratings, giving rise to a U-shaped line, with asymmetric effects: the size of the effect of online reviews depends on whether they are positive or negative.     

Technology adoption: does labour skill matter? Evidence from Portuguese firm-level data

This paper investigates the effect of labour characteristics on the decision to adopt new technologies. As a potential endogeneity problem might arise, we implement estimation techniques that control for endogenous covariates. The results suggest that the share of skilled employees has a significant positive impact on the likelihood of adoption, providing an additional and interesting insight in understanding technology adoption. We also find that firms’ nationality does not matter to the adoption process. The transfer of technology due to foreign investment may not be a widespread phenomenon, casting doubts on the standard internalization theory of foreign direct investment.

Cycling in a changed climate

The use of bicycle is substantially affected by the weather patterns, which is expected to change in the future as a result of climate change. It is therefore important to understand the resulting potential changes in bicycle flows in order to accommodate adaptation planning for cycling. We propose a framework to model the changes in bicycle flow in London by developing a negative binomial count-data model and by incorporating future projected weather data from downscaled global climate models, a first such approach in this area. High temporal resolution (hourly) of our model allows us to decipher changes not only on an annual basis, but also on a seasonal and daily basis. We find that there will be a modest 0.5% increase in the average annual hourly bicycle flows in London’s network due to a changed climate. The increase is primarily driven by a higher temperature due to a changed climate, although the increase is tempered due to a higher rainfall. The annual average masks the differences of impacts between seasons though – bicycle flows are expected to increase during the summer and winter months (by 1.6%), decrease during the spring (by 2%) and remain nearly unchanged during the autumn. Leisure cycling will be more affected by a changed climate, with an increase of around 7% during the weekend and holiday cycle flows in the summer months.     

市盈率计算方法、信息含义及其适用范围的统计研究

市盈率因其结构简单、易懂易学、数据易取得，在我国的价值评估和投资决策中广泛应用。市盈率有多种不同的计算方法，不同计算方法的含义不尽相同，致使市盈率的使用并不简单。为更好运用市盈率，本文比较研究了市盈率不同计算方法下的结果差异、决策信息含义以及适用范围，以期为认识及应用市盈率提供参考。     

Will Markets Direct Investments Under the Kyoto Protocol? Lessons from the Activities Implemented Jointly Pilots

Under the Kyoto Protocol, countries can meet treaty obligations by investing in projects that reduce or sequester greenhouse gases elsewhere. Prior to ratification, treaty participants agreed to launch country-based pilot projects, referred to collectively as Activities Implemented Jointly (AIJ), to test novel aspects of the project-related provisions. Relying on a ten-year history of projects, we investigate the determinants of AIJ investment. Our findings suggest that review-agency preferences related to national political objectives and possibly deeper cultural ties influenced project selection and limited the number of AIJ projects. Bilateral ties also appear to have affected investment decisions directly, possibly because of related transaction costs. The results suggest an investment process different from the assumptions that underlie well-known estimates of cost-savings related to the Protocol’s flexibility mechanisms. We conclude that if approaches developed under the AIJ programs to approve projects are retained, the scale of investment under Kyoto’s flexibility provisions and their cost-savings will be less than what is generally anticipated and the pattern of investment less driven by abatement costs.