Some remarks on the physical models concerning two different approaches to inference in statistical process control

Summary For technological applications it can be useful to identify some simple physical mechanisms, which, on the basis of the available knowledge of the production process, may suggest the most appropriate approach to statistical control of the random quantities of interest. For this purpose the notion of rupture point is introduced firstly. A rupture point is characterized bym randomly arising out of control states, assumed to be mutually exclusive and stochastically independent. Shewhart's control charts seem to represent the natural statistical tool for controlling a rupture point; however it is shown that they are fully justified only when the hazard rates attached to the causes of failure are constant. Otherwise, typically in the presence of time increasing hazard rates, Shewhart's control charts should be completed by a preventive intervention rule (preventive maintenance). In the second place, the notion of dynamic instability point is introduced, which is specifically characterized by assuming that the random quantity of interest is ruled by a stochastic differential equation with constant coefficients. By discretization, developed according to a possibly new approach, it is shown that the former model reduces to an equation error model, which is among the simplest used in adaptive control, and thus particularly easy to deal with in regard to parameter estimation and the definition of the optimum control rule.     

Measuring credibility of compensatory preference statements when trade-offs are interval determined

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.     

Comparative probability for conditional events: A new look through coherence

We study, from the standpoint of coherence, comparative probabilities on an arbitrary familyE of conditional events. Given a binary relation ·, coherence conditions on · are related to de Finetti's coherent betting system: we consider their connections to the usual properties of comparative probability and to the possibility of numerical representations of ·. In this context, the numerical reference frame is that of de Finetti's coherent subjective conditional probability, which is not introduced (as in Kolmogoroff's approach) through a ratio between probability measures.Another relevant feature of our approach is that the family & need not have any particular algebraic structure, so that the ordering can be initially given for a few conditional events of interest and then possibly extended by a step-by-step procedure, preserving coherence.     

The Legacy of the Great Recession in Italy: A Wider Geographical,Gender, and Generational Gap in Working Life Expectancy

Under the pressure of population aging the Italian pension system has undergone reforms to increase labor force participation and retirement age, and, thus, the length of working life. However, how the duration of working life has developed in recent years is not well understood. This paper is the first to analyze trends in working life expectancy in Italy. We use data from a nationally representative longitudinal sample of 880,000 individuals from 2003 to 2013 and estimate working life expectancy by gender, occupational category, and region of residence using a Markov chain approach. We document large and increasing heterogeneity in the length of working life. From 2003–2004 to 2012–2013, working life expectancy for men declined from 35.2 to 27.2 years and for women from 34.7 to 23.7 years, increasing the gender gap to 3.5 years. Both young and old were hit, as roughly half of the decline was attributable to ages below 40, half above 40. Working life expectancy declined for all occupational groups, but those in manual occupations lost most, 8.5 years (men) and 10.5 years (women). The North–South economic gradient widened such that men living in the North were expected to work 8 years longer than women living in the South. The fraction of working life of total life expectancy at age 15 declined to record lows at 40% for men and 34% for women in 2012–2013. Policies aiming at increasing total population working life expectancy need to take into consideration the socio-demographic disparities highlighted by our results.

     

A Stochastic Model to Assess the Effect of Meat Inspection Practices on the Contamination of the Pig Carcasses

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.     

Female Labor Supply,Human Capital,and Welfare Reform

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.     

Rationalité, relativisme, évolution sociale. Une analyse critique du modèle cognitiviste de Boudon-Weber

Cet article traite, en premier lieu, du problème de la définition d'une méthode d'enquête, appropriée à l'analyse et à la compréhension de la réalité sociale. Il le fait en partant de la critique du modèle cognitiviste-comportementaliste que l'on peut relier aux noms de Boudon et Weber. Les intérêts, mais aussi et surtout les carences de ce modèle sont mis en évidence. Etant donné qu'il occupe, parmi les schémas méthodologiques apprêtés à la recherche sociologique, une place d'honneur pour sa rigueur et sa fécondité analytique, ses carences soulignent avec une clarté particulière non seulement les difficultés que la pensée sociale rencontre dans le domaine de la méthode, mais aussi les conséquences négatives de celles-ci sur la scientificité de l’élaboration théorique, entendue comme la capacité à interpréter et à expliquer la réalité de référence.

La critique de l’élaboration de R. Boudon sur la méthode aide aussi à mettre en évidence, par contraste, les motifs, les caractéristiques et les potentialités de notre proposition méthodologique, qui est présentée tout de suite après. Sur la base de cette proposition, que nous appelons objectivisme social, nous avons formulé non seulement des objections au relativisme culturel de Weber et à l'anti-relativisme culturel et cognitif de R. Boudon, mais aussi à la notion de rationalité et à la théorie sur l’évolution sociale de ce dernier auteur.

Parallèlement, sont proposées une notion de rationalité différente et une explication alternative des processus sociaux, laquelle embrasse des aspects concernant tant l’évolution que l'organisation des sociétés humaines et qui peut être facilement étendue aussi à l'interprétation des processus historiques.     

Cytometry inference through adaptive atomic deconvolution

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.     

Cruel Pessimism and Waiting for Belonging: Towards a Global Political Economy of Affect

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.