NCube/papyrus huggingface dataset:
Essays in empirical asset pricing

This thesis has three chapters in which I develop tools for comparisons and dynamic analysis of linear asset pricing models.  In the first chapter, I introduce the notion of dynamically useless factors: factors that may be useless (uncorrelated with the assets returns) at some periods of time, while relevant at other periods of time. This notion bridges the literature on classical empirical asset pricing and the literature on useless factors, where both assume that the relevance of a factor remains constant through time. In this new framework, I propose a modified Fama-Macbeth procedure to estimate the time-varying risk premia from conditional linear asset pricing models. At each date, my estimator consistently estimates the conditional risk premium for every useful factor and is robust to the presence of the dynamically useless ones. I apply this methodology to the Fama-French five-factor model and find that, with the exception of the market, all the factors of this model are dynamically useless, although they remain useful 90 percent of the time.  In the second chapter, I infer the time-varying parameters of a potentially misspecified stochastic discount factor (SDF) model. I extend the model of Gospodinov et al. (2014) to the framework of conditional SDF models, as the coefficients and the covariances are allowed to vary over time. The proposed misspecification-robust inference is able to eliminate the negative effects of potential useless factors, while maintaining the relevance of the useful ones. Empirically, I analyze the dynamical relevance of each factor in seven common asset pricing models from 1963 to 2016. The Fama-French’s three-factor model (FF3) and five factor model (FF5) have been the overall best SDFs in the last 50 years. However, since 2000, the best SDF is CARH (FF3 + momentum factor), followed by FF5 as the second best. Apart from traded factors, the results bring a nuance on non-traded factors. We analyze the relevance, for linear pricing, of a human capital model inspired by Lettau & Ludvigson (2001) and Gospodinov et al. (2014).  The third chapter proposes a method for ranking Fama-French linear factor models according to investors’ preference for higher-order moments. I show that adding a new Fama- French factor to a prior Fama-French model systematically leads to a better model, only when the preference for higher-order moments is moderate (in absolute value). When the preference for higher-order moments is important or extreme, the four-factor model of Carhart (1997) has a better pricing ability than all the Fama-French models. An analysis of models with non-traded factors confirms the relevance, for linear pricing, of the human capital model analyzed in the second chapter. However, I show that this relevance is effective only for investors with null or very low preferences for higher-order moments.

Keyphrases: Distance de Hansen-Jagannathan, Useless factors, Risk premium, Stochastic discount factors, Misspecified models, Hansen-Jagannathan distance, Discrepancy functions, Higher-order moments
Groupes de cobordisme lagrangien immergé et structure des polygones pseudo-holomorphes

In this thesis, we shall study Floer theory for Lagrangian immersions. In the first chapter, we prove a decomposition theorem for pseudo-holomorphic disks with boundary on a given generic Lagrangian immersion. We apply this result to the computation of certain Floer complexes. We conclude with work in progress on the computation of the obstruction of the surgery of two transverse Lagrangian submanifolds. In the second chapter, we consider surfaces. We show that a cobordism group, whose relations are given by unobstructed immersed lagrangian cobordisms, is isomorphic to the Grothendieck group of the derived Fukaya category. We also compute the immersed Lagrangian cobordism group.

Keyphrases: Lagrangian submanifolds, Lagrangian immersions, Holomorphic polygons, Lagrangian cobordisms, Cobordism groups, Floer homology, Fukaya categories
Étude d’équations à retard appliquées à la régulation de la production de plaquettes sanguines

The object of this thesis is the study, using mathematical models, of the regulation mechanism maintaining an optimal quantity of blood platelets. The first chapter presents the biological and mathematical context of the thesis. In a second chapter, we introduce a model for platelet production assuming a regulation by the platelet quantity of both the differentiation rate of stem cells to the platelet cell line and the amount of platelets produced by each megakaryocyte. We show that the dynamic of this model corresponds to a delay differential equation x'(t) = −γx(t)+f(x(t))g(x(t−τ)), and we obtain for this equation new sufficient conditions for stability and for the oscillation of solutions. In a third chapter, we analyze a second model for platelet production in which the regulation is continuous through the maturation speed of megakaryocyte progenitors. The stability analysis requires to adapt a pre-existing framework to problems where the bifurcation parameter is not the delay, and allows to show that increasing the death rate of megakaryocyte progenitors leads to the onset of periodic solutions, in agreement with clinical observation of amegakaryocytic cyclical thrombocytopenia. The last chapter covers a differential equation with two delays that appears among others in a model of platelet production which considers that platelet death can both age-independent and age-dependent.

Keyphrases: oscillations, platelet, cyclical thrombocytopenia, stability analysis, oscillations, delay, transcendental equation, Hopf bifurcation
Les récits en réseaux : manifestations sociotechniques du phénomène choral et l’émergence intermédiatique d’un nouveau type de spectateur

The hyperlink film became popular in the 1990s, part of a particular sociotechnical context that greatly changes the way we think and perceive the world. This thesis argues that the exponential presence of hyperlink films on international screens from the 1990s is one of the symptoms of the appearance of a new type of spectator, whom showcases new habits and reading skills, which encourage multitasking and activate more his working memory. This spectator was able to emerge under a precise conjuncture of elements that revolves around the central and paradoxical notion of network. Moreover, the Internet is a reflection and incarnation of that notion that is both problematic and fascinating. We discuss the role that the Internet play in the changes we propose from the 1990s onward by reconciling its dynamics with a form of narrativity. Beyond the hyperlink form in cinema and hypermedia, we explore the structure of certain television series that became more complex at the same period. This new type of spectator is better able to engage in complex, fragmented and multi-narrative works in the information era of the network society. In the end, this thesis establishes a dialogue between the structure of the hypermedia, TV seriality and the network society and draws the outlines of a new spectatorial model, based on an interdisciplinary approach.

Keyphrases: internet, Network, Ensemble films, Network narratives, Spectator, Interactivity, Complexity
La mode française : vecteur d'influence aux États-Unis de l'après-guerre à l'orée des années 1960

This thesis is a survey of a rarely studied field of international relations. It is interested in the role of women’s sartorial fashion within the Franco-American postwar relations between 1946 and 1960. The analysis takes on the French perspective through the prism of the public authorities and diplomatic bodies, Parisian couturiers, and textile manufacturers. This orientation highlights the two fields on which these actors wish to see manifest an influence of fashion in the United States, namely commercial and prestige propaganda. In their perspective, these two forms of propaganda can be implemented either through indirect actions (press coverage of their fashion shows) or direct actions (shows organized to promote specific products or French production as a whole). The analysis is then completed by integrating the perspective of American fashion professionals (specialized press, manufacturers and retailers) and that of the American diplomatic bodies in France, and the study of customs statistics in order to evaluate, from the viewpoint of these historical actors, the degree of success of fashion as an instrument of French influence in the United States in regard of the initial French expectations.  The research question answered by this thesis is: How important is fashion as an instrument of French influence in the United States after the Second World War? In order to answer it, the analyses procedes in three steps. On the one hand, the intersection of the historical contexts of fashion and Franco-American relations highlights the importance of the advent of the American superpower. This requires the French to adapt in terms of their production methods and their relationship to the American perspective of liberal and democratic modernity. On the other hand, the research was based on a chronological approach distinguishing between the 1946-51 and 1952-60 periods. The first one precedes the state intervention in favor of the Parisian couturiers and the second one is dominated by the state-sponsored Aid to Parisian couture.  The thesis shows that the commercial influence of Parisian fashion in the United States did not materialize contrary to the couturiers’ claims and to the textile industrialists’ expectations. However, with respect to its influence through prestige propaganda, the situation is quite different. Long regarded as an ersatz to the commercial purpose of propaganda by the state – with the exception of the French diplomatic bodies that particularly appreciate its prestige purpose –, from 1957, France’s “rayonnement” through the dissemination of fashion ideas becomes key to French leaders. From then on, its role is to take advantage of the craving for Parisian fashion ideas to ensure a French presence – beyond fashion – in the American market: a mass market otherwise difficult to penetrate, being the largest in the world.

Keyphrases: France, Mode, Influence transnationale, United States, International relations, Commercial relations, Fashion, Transnational influence, Propaganda
Des grandes machines et des petites personnes : les impacts des projets miniers sur les parcours de vie des habitants de deux villes de l’Abitibi

In the early 19th century, an ambitious agricultural, and then, mining colonisation project, leads thousands of people to move to Abitibi, a region located north of Quebec. Over the years that followed, the official narratives highlighting the local economical benefits will often contrast with the lived experience of social and economical instability produced especially within the mining industry. In this context, this research focuses on two Abitibi mining towns that developed around significantly distinct scenarios. On one side, Rouyn-Noranda had become the region’s administrative center, combining an important governmental sector with a mining industry that often pushes its workers to face relocations through constant fly-in fly-outs. On the other side, Malartic, a small town of around 3000 inhabitants, has been going through controversial debates since 2006 following the presentation and later construction of an open pit gold mine site, displacing around 200 buildings. Throughout this thesis, I propose a phenomenological approach in order to discuss the complexity of the impacts of such public policies over the local population, as well as the power balance implied by the simplification of this complexity by privileged actors designing the mainstream narratives around these projects. Lastly, I develop the concept of big machines so as to assist us in the understanding of phenomena characterised by an extraordinary strength, presented under a narrative of control that hides a strategy that seeks the production of ignorance, as well as the consequences of such dynamics over the life course of local inhabitants and mining workers.

Keyphrases: Abitibi, mines, grandes machines, ignorance, planification, industry, big machines, mining towns, public policy, complexity, phenomenology, planning, life course, risks
Makkoto umai zeyo, this is truly delicious : the social construction of taste in the region of Kōchi, Japan

The food of Kōchi is more than mere sustenance to the inhabitants of the region as it is both a way to divide the social world and an economic asset. Based on fieldwork in this region of rural Japan, this research examines how incorporated beliefs and pragmatic considerations participate in the social construction of taste for emblematic foods in Kōchi. On one hand, this research seeks to uncover how incorporated beliefs, values that are learnt, embodied, performed and transmitted, structure taste in the region. Habitus, culture and identity are some of the tools at our disposal to analyze how standards of taste are incorporated into people’s daily lives. Literally speaking, we taste the social world through the food we eat. On the other hand, this research investigates how pragmatic considerations and immediate concerns brought on by material conditions help fashion taste in Kōchi. In one of the poorest prefectures of Japan, the urgent need for revitalization makes the cuisine of the region a valuable resource for the residents of the region. Economic opportunities, government strategic planning and the forces of capitalism fuel the creation of new dishes and the promotion of traditional flavors. Thus, embedded representations that give meaning to food and regimes of values that ascribe worth to food shape residents palates. Finally, such an analysis needs to recognize that both taste preferences (i.e. the choices we make) and taste perceptions (i.e. how we experience flavor) are closely bound together. The social construction of taste is part of an integrated system that frames culinary choices as well as the sense of taste. A comprehensive model that combines complementary facets of what constitutes taste can further contribute to a better understanding of the contextual nature of deliciousness.

Keyphrases: Regional cuisine, Japan, Rural revitalization, Social Construction of Taste
Comment l’ancienneté et le degré de résolution de problèmes associé à la tâche modulent-ils l’impact du leadership d’habilitation sur la performance à la tâche ?

This research focuses on the impact of empowerment leadership on task performance, taking into account two moderating variables: the tenure and the degree of problem solving associated with the task. Based on the substitutes for leadership theory, as well as on the job demands-resources theory, it was expected that the contribution of empowerment leadership to performance would be greater when employee tenure was low and problem solving associated with the task of the employee was high. Moderation hypotheses were tested using the answers to questionnaires of 324 employees and their immediate supervisor from 17 organizations working in various sectors. The results of regression analyze indicate a positive and significant link between empowerment leadership and task performance. On the other hand, the anticipated moderation hypotheses are not supported. These results are discussed and implications for theory and practice are stated.

Keyphrases: Empowerment leadership, Task performance, Tenure, Complex problem solving associated with the task, Interaction effect
Recherche-action et recherche collaborative : quel rapport aux savoirs et à la production de savoirs?

Over the last fifteen years or so, various types of participatory research have been growing in popularity, including action research and collaborative research. They all adopt a more symmetrical relationship between the research scientists and practitioners and a concern for the development of these professionals; however, some of their underlying theoretical/epistemological hypotheses and the methodological approach differ. This contribution is meant to present both types of research to clarify issues and challenges specific to them, and to reflect on their relationship with knowledge and knowledge production.

Keyphrases: Action research, Collaborative research, Knowledge production, Situated knowledge, Professional development
Mécanismes modulant la stabilité de l’ARNm alphaENaC des cellules épithéliales alvéolaires dans un environnement inflammatoire

The epithelial sodium channel (ENaC) expressed in alveolar epithelial cells plays an important role in lung liquid clearance at birth and in acute respiratory distress syndrome (ARDS). Preliminary work in the laboratory has shown that TNF-α downregulates expression of αENaC mRNA in part via post-transcriptional modulation of its stability. In the present study, five 3'UTR αENaC sequences that are highly conserved (CS) across different species were studied to determine the impact of each of them on the modulation of αENaC mRNA under basal conditions, as well as in the presence of TNF-α. To study the involvement of these CS on the modulation of αENaC mRNA, a Tet-Off model was used to inhibit transcript expression using doxycycline. Transcript levels over time were estimated by RT-qPCR. With this technique, the half-life of αENaC mRNA is ~100 min. Punctual deletion mutants of 3'UTR were generated by specifically removing the CS1 (31pb), CS3 (22bp), CS2&3 (82bp), CS4&5 (74bp), CS1-5 (187bp) and CS3+ (165bp) domains. Our results show that the deletion of each CS affects their respective half-lives at 169 min, 172 min, 246 min, 193 min, 208 min and 237 min. The stability of the different mutants was then evaluated in the presence of TNF-α (a cytokine found in the lungs of patients with ARDS). In the presence of the complete 3’UTR, the degradation curve of the mRNA in presence of TNF-α was different from the one observed in under basal conditions. In presence of TNF-α, the curve turns biphasic with a rapid degradation followed by a plateau at about 50% of the expression level. The same thing was observed for the deletion mutant CS1-5. We therefore conclude that in general the 3'UTR of αENaC mRNA via the conserved domains is involved in the destabilization of the transcript. CSs studied did not contribute to the decreased expression of αENaC mRNA in the presence of TNF-α. However, we cannot exclude the possibility that other 3’UTR sequences could play an important role in the rapid degradation of αENaC mRNA during inflammation or lung injury.

Keyphrases: inflammation, TNF-alpha, epithelial sodium channel (ENaC), messenger RNA, stability, 3' untranslated region (3'UTR), half-life, alveolar epithelial cells, ARDS
Promoting healthy body images in populations : does body dissatisfaction influence reactions to Québec’s charter for a healthy and diverse body image?

Background: There is considerable concern around the increasing prevalence of unhealthy  eating behaviours and attitudes, disordered eating, and eating disorders. However, little is  known regarding how individual body image and size influence the way in which populations  understand, interpret, and react to initiatives designed to promote healthy body images.  Objectives: Using a population-based sample, we examined the relationship between body  dissatisfaction (BD) and perception of the Québec Charter for a Healthy and Diverse Body  Image (CHIC) and the moderating effects of BMI, age, and sex in this association. Methods:  Participants included 1738 Québec adult respondents to an online survey. Multivariate logistic  regression models were created to estimate odds ratios (OR) between BD and level of  favourability to the CHIC and to test potential interaction effects between one’s BMI category,  age, and sex with BD. Analyses were adjusted for household income, education, and  immigration status. Results: Analyses suggested that those with greater BD were less likely to  be unfavourable towards the CHIC compared to those who have no BD (OR= 0.38; 95% CI:  0.23-0.63). Respondents who were men (OR= 3.70; 95% CI: 2.12-6.43), overweight (OR=1.95;  95% CI: 1.00-3.80), obese (OR=2.91; 95% CI: 1.43-5.91), or had less than high school  education (OR=1.93; 95% CI: 1.10-3.41) were more likely to be unfavourable towards the  CHIC. Younger adult respondents were also less likely to be unfavourable (OR= 0.15, 95% CI  0.03-0.71) and those participants who had an underweight BMI were found to be significantly  more likely to be unfavourable to the CHIC (OR= 10.68; 95% CI: 2.03-56.10). No moderating  effects of BMI, age, or sex on the relationship between BD and level of favorability for the  CHIC were detected. Conclusions: This study presents one of the first efforts to examine the  impact of individual risk factors on the uptake of health promotion initiatives. Results indicate  that current body image discrepancy substantially influences the uptake of a population-based  initiative to promote healthy body image. This is a finding that requires replication and  extension.

Keyphrases: Body dissatisfaction, Body image, Body mass index, Québec Charter for a Healthy and Diverse Body Image, Health promotion, Individual perception
Negotiating insecurity? : a comparative study of collective bargaining in retail food in Canada, Germany, Sweden and the United States

Risk refers to the economic uncertainties encountered by workers. These include how forms of wage instability, scheduling uncertainty, and the erosion of traditional employee benefit structures are negatively affecting their material welfare and ability to plan for the future.  This thesis speaks to scholarly debates on the nature and causes of worker risk. It does so by exploring the evolution of risks in unionised workplaces. This is achieved in two ways. First, the study seeks to provide insights on the nature of risk trends in unionised settings over time. Second, it explores the impacts of actor strategies (unions, employers, states) on risk outcomes in collective bargaining across different organisational and institutional settings.  This thesis develops a novel theoretical framework for understanding risk, incorporating three dimensions (generosity, individualisation, and segmentation). Each dimension adds value to the exploration of risks over time in the organisations under investigation. Different literatures are also mobilised to examine how, in different contexts (organisational and institutional) and with different actors and their attributes (power), actor strategies shape outcomes across these three dimensions.  Contextualised case-studies were conducted for this study. This thesis investigates experiences in retail food – a sector and industry typically associated with work practices that drive economic insecurity. The research design entails a longitudinal (1980-2016) comparison of eight supermarket chains (cases) in two liberal market economics (Canada and the United States) and two coordinated market economies (Germany and Sweden).  The thesis is structured in three overview chapters (research question, theoretical approaches, operationalisation), three separate articles presenting different aspects of the research findings, and an analytical overview chapter discussing key results in the context of the broader literature and with regard to their implications.  Several contributions stem from these findings. First, this thesis demonstrates how risks have not only increased across the chains, but that these increases differ in their form and intensity across three dimensions. These differences have implications for how we measure risks and explain their trajectories. Second, this thesis finds that actor strategies matter to risk, yet that their outcomes can only be understood in relation to contextual variables. It also points to the importance of union power to the effectiveness of these strategies in mitigating the risks experienced by workers in these different organisational and institutional contexts.

Keyphrases: Risk, Collective bargaining, Retail, Comparative employment relations, Precarious work