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71.
The frequency of use and the marginal costs and marginal value products of mastitis control practices on somatic cell count (SCC) and milk yield are investigated. A survey of current management practices is combined with Dairy Herd Improvement production information to determine the relationships between milk yield, SCC, management practices, and production and producer characteristics under field conditions. The relationships are modeled and compared at the cow and herd level. A moment-generating approach is used in the herd model to determine which, if any, practices are risk reducing. The SCC for an individual cow is a better indicator of milk production lost due to mastitis than is a bulk tank SCC. Most recommended mastitis control practices are estimated to be economically beneficial, but some common practices are found not to be economical, and questions are raised about dry cow treatment. On a examiné la fréquence à laquelle on recourt aux pratiques de lutte contre la mammite, de même que les couts et les avantages marginaux de ces dernières en ce qui concerne la numération des cellues somatiques et le rendement laitier. On a combiné une enquête sur les pratiques zootechniques actuelles aux renseignements sur la production extraits du Programme d'amélioration des troupeaux laitiers en vue de déterminer les relations qui existent entre le rendement laitier, la numération des cellules somatiques, la conduite du troupeau ainsi que les caractéristiques associées à la production et aux producteurs, sur le terrain. On a ensuite modélisé ces relations et on les a compareées entre les animaux et les troupeaux. Pour le modèle touchant les troupeaux, on s'est servi d'une approche générant des moments, pour déterminer si une pratique quelconque diminuait les risques. La numération des cellules somatiques chez la vache est un meilleur indicateur du volume de lait perdu à la suite de la mammite que la numération des cellules somatiques dans la citerne. La plupart des méthodes de lutte contre la mammite recommendées offrent un avantage économique, mais certaines pratiques courantes ont l'effet contraire et on s'interroge sur l'utilité de traiter les vaches taries.  相似文献   
72.
Recent research has highlighted the quantitative contribution to merger analysis from extending unilateral effects models to understand the payoffs to future potential coordinated effects. Some of the emphasis of this research appears to have made its way into the 2010 Horizontal Merger Guidelines. In this paper, we demonstrate the quantification of coordinated effects in an oligopoly and procurement model, and we show that screens that are based on upward pricing pressure are not adequate in mergers where coordinated effects are a potential concern.  相似文献   
73.
T. P. Hutchinson MA  PhD 《Metrika》1981,28(1):263-271
Summary Bivariate distributions, which may be of special relevance to the lifetimes of two components of a system, are derived using the following approach. As the two components are part of one system and therefore exposed to similar conditions of service, there will be similarity between their lifetimes that is not shared by components belonging to different systems. The lifetime distribution for a given system is assumed to be Gamma in form (this includes the exponential as a special case; extension to the Stacey distribution, which includes the Weibull distribution, is straightforward). The scale parameter of this distribution is itself a random variable, with a Gamma distribution. We thus obtain what might be termed a compound Gamma-Gamma bivariate distribution. The cumulative distribution function of this may be expressed in terms of one of the double hypergeometric functions of Appell.Generalised hypergeometric functions play an important part in this paper, and one of Saran's triple hypergeometric functions is obtained when generalising the above model to permit the scale parameters of the distributions for the two components to be correlated, rather than identical.Work started while the author was with the Transport Studies Group, University College London.  相似文献   
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New products or services often misalign with customer preferences, and sometimes these initial offerings must be abandoned and replaced. Factors influencing these “complete pivot” decisions are poorly understood. We use behavioral decision theory to develop a theoretical model of pivot decisions that tests our predictions via a conjoint analysis experiment. We find that magnitude of the miss (revenues compared to plan), length of the runway (cash available/burn rate), and attribution for the miss (reason for customer misreads) significantly influence complete pivot decisions, and we simultaneously consider interactions. Individual grit and impulsiveness also shape the effects of some attributes.  相似文献   
79.
Globally, society has been facing several and growing health problems, which increased the importance of efforts towards social change. In this context, using social marketing to create and implement programs that foster behavioural change has increased in the public health community. One of the health problems that society has been facing is the unceasing need for blood products, so the subject of blood donation became an important research topic in the area of social marketing, as social marketing strategies can contribute to solving this problem. It is essential to understand the factors that motivate individuals to donate blood, to enhance the recruitment and retention of blood donors. Our study aims at evaluating the key personality factors that influence blood donation behaviour to reach a higher understanding of what concerns this global issue. The method used to analyse the data is ANOVA. We conclude that the Personality of potential donors is significantly different from the non-donors' regarding Openness to Experience and Agreeableness. These results suggest that potential donors might perceive blood donation, as well as the associated barriers, differently from non-donors. Based on our findings, we suggest some perspectives for future research in this area.  相似文献   
80.
Procedural consolidation, as a solution to the rescue of insolvent multinational corporate groups (‘MCGs’), is said to be able to preserve group value for creditors. This article explores the desirability of procedural consolidation in the EU in the light of theories of corporate rescue law, cross‐border insolvency law, multinational enterprises and relevant EU cases with reference to the European Insolvency Regulation. It argues that, based on current cross‐border insolvency rules in the EU, there is an inherent difficulty for procedural consolidation in balancing the goal of preservation of group value and the goal of certainty. The article also considers the new ‘group procedural coordination proceedings’ offered by the Recast European Insolvency Regulation and argues that it may help to supplement the gap left by the procedural consolidation in the EU. Copyright © 2017 INSOL International and John Wiley & Sons, Ltd.  相似文献   
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