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1.
This paper studies a single-product distribution channel where a supplier manufactures items of a given type, some of which are defective, that are sold by a retailer who only detects a subset of the defective items, passing the rest along to customers. We conjecture the structure of the demand and cost functions, assuming customers to have a decreasing marginal aversion to bad quality while both the supplier and the retailer make marginally increasing efforts to avoid bad quality. This allows us to deduce several implicit parameters of a cost model based on observable data, such as the share of the channel margin. Once the parameters of the model are available, we analyze the result of vertical integration. Although we confirm the well-known fact that vertical integration improves the quality perceived by the customer, we characterize the supplier's decision of whether or not to provide a better quality in terms of the individual channel margins. As an alternative, we derive the conditions under which the supplier and the retailer may devise a mutually beneficial transfer contract that simultaneously increases their profit and improves quality.  相似文献   
2.
This paper studies how an overall fuzzy preference relation can be constructed in the compensatory context of the simple additive difference model, when imprecision on the trade-offs has to be taken into account. Three credibility indices of preferences are analysed and illustrated by a numerical example. Arguments are presented supporting the use of the third index, for which an interesting transitivity property (which was an open problem) is proved.  相似文献   
3.
The objective of meat inspection is to promote animal and public health by preventing, detecting, and controlling hazards originating from animals. With the improvements of sanitary level in pig herds, the hazards profile has shifted and the inspection procedures no longer target major foodborne pathogens (i.e., not risk based). Additionally, carcass manipulations performed when searching for macroscopic lesions can lead to cross‐contamination. We therefore developed a stochastic model to quantitatively describe cross‐contamination when consecutive carcasses are submitted to classic inspection procedures. The microbial hazard used to illustrate the model was Salmonella, the data set was obtained from Brazilian slaughterhouses, and some simplifying assumptions were made. The model predicted that due to cross‐contamination during inspection, the prevalence of contaminated carcass surfaces increased from 1.2% to 95.7%, whereas the mean contamination on contaminated surfaces decreased from 1 logCFU/cm² to ?0.87 logCFU/cm², and the standard deviations decreased from 0.65 to 0.19. These results are explained by the fact that, due to carcass manipulations with hands, knives, and hooks, including the cutting of contaminated lymph nodes, Salmonella is transferred to previously uncontaminated carcasses, but in small quantities. These small quantities can easily go undetected during sampling. Sensitivity analyses gave insight into the model performance and showed that the touching and cutting of lymph nodes during inspection can be an important source of carcass contamination. The model can serve as a tool to support discussions on the modernization of pig carcass inspection.  相似文献   
4.
We estimate a dynamic model of employment, human capital accumulation—including education, and savings for women in the United Kingdom, exploiting tax and benefit reforms, and use it to analyze the effects of welfare policy. We find substantial elasticities for labor supply and particularly for lone mothers. Returns to experience, which are important in determining the longer‐term effects of policy, increase with education, but experience mainly accumulates when in full‐time employment. Tax credits are welfare improving in the U.K., increase lone‐mother labor supply and marginally reduce educational attainment, but the employment effects do not extend beyond the period of eligibility. Marginal increases in tax credits improve welfare more than equally costly increases in income support or tax cuts.  相似文献   
5.
This article presents an evaluation framework developed to assess the first-level effects of introducing the Standard Days Method (SDM) in Peru Ministry of Health clinics. Four questions are asked: 1) To what extent do providers routinely achieve SDM service delivery standards? 2) Is the time invested in SDM delivery consistent with program norms? 3) How does SDM delivery compare with delivery of established methods? and 4) How does SDM introduction affect delivery of established methods? A study at 62 clinics demonstrated the framework's usefulness. The Standard Days Method introduction had positive overall effects on the quality of care but provider training needed adjustments.  相似文献   
6.
In this paper, we consider a statistical estimation problem known as atomic deconvolution. Introduced in reliability, this model has a direct application when considering biological data produced by flow cytometers. From a statistical point of view, we aim at inferring the percentage of cells expressing the selected molecule and the probability distribution function associated with its fluorescence emission. We propose here an adaptive estimation procedure based on a previous deconvolution procedure introduced by Es, Gugushvili, and Spreij [(2008), ‘Deconvolution for an atomic distribution’, Electronic Journal of Statistics, 2, 265–297] and Gugushvili, Es, and Spreij [(2011), ‘Deconvolution for an atomic distribution: rates of convergence’, Journal of Nonparametric Statistics, 23, 1003–1029]. For both estimating the mixing parameter and the mixing density automatically, we use the Lepskii method based on the optimal choice of a bandwidth using a bias-variance decomposition. We then derive some convergence rates that are shown to be minimax optimal (up to some log terms) in Sobolev classes. Finally, we apply our algorithm on the simulated and real biological data.  相似文献   
7.
Recent theorizations of affect have focused largely on Western historical, political and aesthetic contexts to distinguish between affect and emotion. Notably, these interventions offer new imaginaries to reinvigorate analysis of politics in the face of shrinking possibilities. However, much of this literature views affect as autonomous from emotion, while overlooking the political history of development and the differentiated relation to affect under colonial capitalism in other historical contexts. This paper studies subaltern engagement in activist performance in India to address these issues. It thinks through Lauren Berlant's account of the aesthetic genre and affective structure of cruel optimism, and her focus on historical contexts where people have recently lost the vision of a good life. By contrast, focusing on the historical present of those born into a pervasive and intractable sense of marginality and insecurity, I ask: what is the subject's relation to affect and activism in contexts where the loss of vision of a good life is not new under neoliberalism, but rather, reworks long-standing violence and inclusion/exclusion of colonial capitalism and nation-state histories. I argue that it is useful to understand Berlant's ‘materialist context for affect theory’ in light of uneven global histories of colonialism, development and neoliberalism. The affective experience of time is different across different spaces. As such, this paper contributes a global materialist context for affect theory, by focusing on activist theatre by a tribe called Chhara, designated ‘born criminals’ by British colonial law – a status legally denotified in 1952, but that is practically still effective in postcolonial India. Competing affective structures – sentimental optimism, cruel pessimism, betrayal and ordinary regard – shape and are shaped by Chhara negotiations with branded criminality. Ultimately, for the postcolonial subject, surviving in the neoliberal present involves vacillating among competing affective structures, only some of which generate sustained political critique.  相似文献   
8.
We define the odd log-logistic exponential Gaussian regression with two systematic components, which extends the heteroscedastic Gaussian regression and it is suitable for bimodal data quite common in the agriculture area. We estimate the parameters by the method of maximum likelihood. Some simulations indicate that the maximum-likelihood estimators are accurate. The model assumptions are checked through case deletion and quantile residuals. The usefulness of the new regression model is illustrated by means of three real data sets in different areas of agriculture, where the data present bimodality.  相似文献   
9.
We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run health follow-ups of the interaction between stress and social networks in a human population in which both stress and social networks are arguably exogenous.  相似文献   
10.
The study aimed to conduct a literature review as a step of the development of a new questionnaire about the nursing workers' perception of job factors that may lead to musculoskeletal symptoms. An information synthesis was achieved by collecting data from studies that fitted the search criteria. The results showed that despite the existence of several job factors related to musculoskeletal symptoms, no specific questionnaire that evaluates this relationship was found. Therefore, this literature review presents important topics for developing the first questionnaire to analyze work activities that may contribute to pain and discomfort among nursing personnel.  相似文献   
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