Many economists and policy analysts have conducted studies on crop insurance. Three research gaps are identified: i) moral hazard in prevented planting (PP), ii) choice of PP and planting a second crop, and iii) selecting margin protection in the Dairy Margin Protection Program (MPP-Dairy). The first essay analyzes the existence of moral hazard in PP. The PP provision is defined as the “failure to plant an insured crop by the final planting date due to adverse events”. If the farmer decides not to plant a crop, the farmer receives a PP indemnity. Late planting (LP) is an option for the farmer to plant a crop while maintaining crop insurance after the final planting date. Crop insurance may alter farmers’ behavior in selecting PP or LP and could increase the likelihood of PP claims even though farmers can choose LP. This study finds evidence that a farmer with higher insurance coverage tends to choose PP more often (moral hazard). Spatial panel models attest to the existence of moral hazard in PP empirically. If a farmer chooses PP, s/he receives the PP indemnity and may either leave the acreage unplanted or plant a second crop, e.g., soybean for corn. If the farmer plants a second crop after the PP claim, the farmer receives a 35% of PP payment. The current PP provision fails to provide farmers with an incentive to plant a second crop; 99.9% of PP claiming farmers do not plant a second crop. Adjusting PP indemnity payment may encourage farmers to plant a second crop. The second essay explores this question using a stochastic simulation and suggests to increase the PP payment by 10%-15%. The third essay investigates why Wisconsin dairy farmers purchase more supplementary protection than California farmers in a MPP-Dairy introduced in the 2014 Farm Bill. MPP-Dairy provides dairy producers with margin protection when the national dairy margin is below a farmer selected threshold. This study determines whether conditional probabilities regarding regional and national margins have a role in farmer’s decision-making to purchase supplementary coverages using Copula models. Results indicate that Wisconsin farmers have higher conditional probabilities and purchase more buy-up coverages.

La recherche se développe dans une agence d’accueil au public. Les accueils sontréalisés en face à face et demandent de la part du travailleur des échanges discursifs quitraitent de la non-réalisation des services sollicités ou du non-respect des délais. La tension estexplicite. Faire face à ces situations de réclamation du public contre l’entreprise, légitimes ounon, fait que les réceptionnistes maintiennent un effort mental intense et prolongé.L’objectif général de la thèse est d’avancer un peu plus dans la singularité des sujets ensituation de travail et de contribuer à ce que les travailleurs puissent se développer ettransformer l’activité dans le but de diminuer les conflits dans l’accueil et, par conséquent,l’affection mentale.Nous cherchons donc une théorie et une pratique qui puissent mieux contribuer à révélerle sens des situations à partir de l’appréhension des expériences subjectives desréceptionnistes. Avec le concept d’ « activité empêchée », dans laquelle les conflitsintrasubjectifs se font présents, nous cherchons comme fil conducteur la clinique de l’activité.Dans ce processus, nous utilisons la méthode de l’auto-confrontation croisée, c'est-à-dire quepar le biais des discussions, des contradictions, dans des situations vécues dans le collectif, lestravailleurs pourraient parvenir à la reconstruction des sens de la propre activité.C’est à partir du terrain de travail, du matériel empirique recueilli dans les autoconfrontationssimples et croisées, qu’a surgi un « instrument » qui a joué le rôle de fil àdérouler : la pause au cours de la journée de travail. Et à partir de la pause, nous cherchons àparvenir aux conflits de l’activité et au possible développement des travailleurs dans l’activité.D’une manière générale, on peut dire que notre objectif est devenu une double questionde la fonction de la pause, d’un côté en tant qu’instrument de développement de l’activité, del’autre en tant qu’objet de reprise du travail à partir du collectif, pour la rénovation du genre.Dans ce problème apparemment simple se concentrent de fortes tensions de l’activité en faceà face, aussi bien individuelle (intrasubjective) que collective (intersubjective) de travail, quipeuvent révéler tout le potentiel de développement des travailleurs dans cette même activité. / The research was developed at a client service agency. The services are carried outface to face and demand from the employee discursive exchanges dealing with the failure tocarry out the requested services or non compliance with deadlines. Tension is explicit.Dealing with situations of complaints from the public against the company, whether thesecomplaints are legitimate or not, makes the attendants exercise continuous and long mentalefforts.The general goal of this research is to advance further in the understanding of thesingularity of the subjects in a work situation and contribute for the workers to be able todevelop and transform the activity, aiming at reducing conflicts during service and, as aconsequence, reducing mental sickness.A theory and practice which may contribute to reveal the meaning of the situationsfrom the apprehension of the subjective experiences of the clerks is then sought. With theconcept of “prevented activity", in which intrasubjective conflicts are present, we search theclinic of the activity as a conducting line. In this process we utilize the method of cross selfconfrontation, that is, by means of the discussions and contradictions in situations experiencedcollectively, the workers might be able to reconstruct the meanings of the activity itself.It was from this work field, from the empirical material collected in the simple andcross self confrontations, that an “instrument” arose to serve as a yarn to be unfolded: Thebreak during the work. And from the break we attempt to get to the conflicts of the activityand to the possible development of the workers in the activity.In a general way, we can say that our objective became the double question of thefunction of the break, on the one hand an instrument of activity development, and on the otheran object of work restart from the collective for gender renewal. In this apparently simpleproblem, strong tensions from the face-to-face activity are concentrated, both individual(intrasubjective) and collective (intersubjective), which may reveal the whole potential ofdevelopment of the workers in this same activity. / A pesquisa se desenvolve em uma agência de atendimento a clientes. Os atendimentos são realizados face a face e demandam do trabalhador trocas discursivas que tratam da não realização dos serviços solicitados ou do não cumprimento dos prazos. A tensão é explícita. Lidar com situações de reclamação do público contra a empresa, legítimas ou não, faz com que os atendentes mantenham um esforço mental intenso e prolongado. O objetivo geral da pesquisa é avançar um pouco mais na singularidade dos sujeitos em situação de trabalho e contribuir para que os trabalhadores possam se desenvolver e transformar a atividade com o intuito de diminuir os conflitos no atendimento e, conseqüentemente, o adoecimento mental. Buscamos, então, uma teoria e prática que melhor pudessem contribuir para revelar o sentido das situações a partir da apreensão das experiências subjetivas dos atendentes. Com o conceito de "atividade impedida", na qual os conflitos intrassubjetivos se fazem presentes, buscamos como fio condutor a clinica da atividade. Nesse processo, utilizamos o método de autoconfrontação cruzada, ou seja, por meio das discussões, das contradições, em situações vivenciadas no coletivo os trabalhadores poderiam chegar à reconstrução dos sentidos daprópria atividade. Foi a partir do campo de trabalho, do material empírico colhido nas autoconfrontações simples e cruzada, que surgiu um «instrumento» que serviu como um fio de novelo a ser desenrolado: a pausa durante a jornada de trabalho. E, a partir da pausa, buscamos chegar aos conflitos da atividade e ao possível desenvolvimento dos trabalhadores na atividade. De forma geral, pode-se dizer que nosso objetivo passou a ser a dupla questão da função da pausa, de um lado como instrumento de desenvolvimento da atividade, de outro como objeto de retomada do trabalho a partir do coletivo para renovação do gênero. Nesse problema aparentemente simples concentram-se fortes tensões da atividade face a face, tanto individual (intrassubjetivas), quanto coletiva (intersubjetivas) de trabalho, que podem revelar todo o potencial de desenvolvimento dos trabalhadores nessa mesma atividade.

Le risque attribuable (RA) mesure la proportion de cas de maladie qui peuvent être attribués à une exposition au niveau de la population. Plusieurs définitions et méthodes d'estimation du RA ont été proposées pour des données de survie. En utilisant des simulations, nous comparons quatre méthodes d'estimation du RA dans le contexte de l'analyse de survie : deux méthodes non paramétriques basées sur l'estimateur de Kaplan-Meier, une méthode semi-paramétrique basée sur le modèle de Cox à risques proportionnels et une méthode paramétrique basée sur un modèle à risques proportionnels avec un risque de base constant par morceaux. Nos travaux suggèrent d'utiliser les approches semi-paramétrique et paramétrique pour l'estimation du RA lorsque l'hypothèse des risques proportionnels est vérifiée. Nous appliquons nos méthodes aux données de la cohorte E3N pour estimer la proportion de cas de cancer du sein invasif attribuables à l'utilisation de traitements hormonaux de la ménopause (THM). Nous estimons qu'environ 9 % des cas de cancer du sein sont attribuables à l'utilisation des THM à l'inclusion. Dans le cas d'une exposition protectrice, une alternative au RA est la fraction préventive (FP) qui mesure la proportion de cas de maladie évités. Cette mesure n'a pas été considérée dans le contexte de l'analyse de survie. Nous proposons une définition de la FP dans ce contexte et des méthodes d'estimation en utilisant des approches semi-paramétrique et paramétrique avec une extension permettant de prendre en compte les risques concurrents. L'application aux données de la cohorte des Trois Cités (3C) estime qu'environ 9 % de cas d'accident vasculaire cérébral peuvent être évités chez les personnes âgées par l'utilisation des hypolipémiants. Notre étude montre que la FP peut être utilisée pour évaluer l'impact des médicaments bénéfiques dans les études de cohorte tout en tenant compte des facteurs de confusion potentiels et des risques concurrents. / The attributable risk (AR) measures the proportion of disease cases that can be attributed to an exposure in the population. Several definitions and estimation methods have been proposed for survival data. Using simulations, we compared four methods for estimating AR defined in terms of survival functions: two nonparametric methods based on Kaplan-Meier's estimator, one semiparametric based on Cox's model, and one parametric based on the piecewise constant hazards model. Our results suggest to use the semiparametric or parametric approaches to estimate AR if the proportional hazards assumption appears appropriate. These methods were applied to the E3N women cohort data to estimate the AR of breast cancer due to menopausal hormone therapy (MHT). We showed that about 9% of cases of breast cancer were attributable to MHT use at baseline. In case of a protective exposure, an alternative to the AR is the prevented fraction (PF) which measures the proportion of disease cases that could be avoided in the presence of a protective exposure in the population. The definition and estimation of PF have never been considered for cohort studies in the survival analysis context. We defined the PF in cohort studies with survival data and proposed two estimation methods: a semiparametric method based on Cox’s proportional hazards model and a parametric method based on a piecewise constant hazards model with an extension to competing risks. Using data of the Three-City (3C) cohort study, we found that approximately 9% of cases of stroke could be avoided using lipid-lowering drugs (statins or fibrates) in the elderly population. Our study shows that the PF can be estimated to evaluate the impact of beneficial drugs in observational cohort studies while taking potential confounding factors and competing risks into account.