Les données de classement, c.à. d. des listes ordonnées d'objets, apparaissent naturellement dans une grande variété de situations, notamment lorsque les données proviennent d’activités humaines (bulletins de vote d'élections, enquêtes d'opinion, résultats de compétitions) ou dans des applications modernes du traitement de données (moteurs de recherche, systèmes de recommendation). La conception d'algorithmes d'apprentissage automatique, adaptés à ces données, est donc cruciale. Cependant, en raison de l’absence de structure vectorielle de l’espace des classements et de sa cardinalité explosive lorsque le nombre d'objets augmente, la plupart des méthodes classiques issues des statistiques et de l’analyse multivariée ne peuvent être appliquées directement. Par conséquent, la grande majorité de la littérature repose sur des modèles paramétriques. Dans cette thèse, nous proposons une théorie et des méthodes non paramétriques pour traiter les données de classement. Notre analyse repose fortement sur deux astuces principales. La première est l’utilisation poussée de la distance du tau de Kendall, qui décompose les classements en comparaisons par paires. Cela nous permet d'analyser les distributions sur les classements à travers leurs marginales par paires et à travers une hypothèse spécifique appelée transitivité, qui empêche les cycles dans les préférences de se produire. La seconde est l'utilisation des fonctions de représentation adaptées aux données de classements, envoyant ces dernières dans un espace vectoriel. Trois problèmes différents, non supervisés et supervisés, ont été abordés dans ce contexte: l'agrégation de classement, la réduction de dimensionnalité et la prévision de classements avec variables explicatives.La première partie de cette thèse se concentre sur le problème de l'agrégation de classements, dont l'objectif est de résumer un ensemble de données de classement par un classement consensus. Parmi les méthodes existantes pour ce problème, la méthode d'agrégation de Kemeny se démarque. Ses solutions vérifient de nombreuses propriétés souhaitables, mais peuvent être NP-difficiles à calculer. Dans cette thèse, nous avons étudié la complexité de ce problème de deux manières. Premièrement, nous avons proposé une méthode pour borner la distance du tau de Kendall entre tout candidat pour le consensus (généralement le résultat d'une procédure efficace) et un consensus de Kemeny, sur tout ensemble de données. Nous avons ensuite inscrit le problème d'agrégation de classements dans un cadre statistique rigoureux en le reformulant en termes de distributions sur les classements, et en évaluant la capacité de généralisation de consensus de Kemeny empiriques.La deuxième partie de cette théorie est consacrée à des problèmes d'apprentissage automatique, qui se révèlent être étroitement liés à l'agrégation de classement. Le premier est la réduction de la dimensionnalité pour les données de classement, pour lequel nous proposons une approche de transport optimal, pour approximer une distribution sur les classements par une distribution montrant un certain type de parcimonie. Le second est le problème de la prévision des classements avec variables explicatives, pour lesquelles nous avons étudié plusieurs méthodes. Notre première proposition est d’adapter des méthodes constantes par morceaux à ce problème, qui partitionnent l'espace des variables explicatives en régions et assignent à chaque région un label (un consensus). Notre deuxième proposition est une approche de prédiction structurée, reposant sur des fonctions de représentations, aux avantages théoriques et computationnels, pour les données de classements. / Ranking data, i.e., ordered list of items, naturally appears in a wide variety of situations, especially when the data comes from human activities (ballots in political elections, survey answers, competition results) or in modern applications of data processing (search engines, recommendation systems). The design of machine-learning algorithms, tailored for these data, is thus crucial. However, due to the absence of any vectorial structure of the space of rankings, and its explosive cardinality when the number of items increases, most of the classical methods from statistics and multivariate analysis cannot be applied in a direct manner. Hence, a vast majority of the literature rely on parametric models. In this thesis, we propose a non-parametric theory and methods for ranking data. Our analysis heavily relies on two main tricks. The first one is the extensive use of the Kendall’s tau distance, which decomposes rankings into pairwise comparisons. This enables us to analyze distributions over rankings through their pairwise marginals and through a specific assumption called transitivity, which prevents cycles in the preferences from happening. The second one is the extensive use of embeddings tailored to ranking data, mapping rankings to a vector space. Three different problems, unsupervised and supervised, have been addressed in this context: ranking aggregation, dimensionality reduction and predicting rankings with features.The first part of this thesis focuses on the ranking aggregation problem, where the goal is to summarize a dataset of rankings by a consensus ranking. Among the many ways to state this problem stands out the Kemeny aggregation method, whose solutions have been shown to satisfy many desirable properties, but can be NP-hard to compute. In this work, we have investigated the hardness of this problem in two ways. Firstly, we proposed a method to upper bound the Kendall’s tau distance between any consensus candidate (typically the output of a tractable procedure) and a Kemeny consensus, on any dataset. Then, we have casted the ranking aggregation problem in a rigorous statistical framework, reformulating it in terms of ranking distributions, and assessed the generalization ability of empirical Kemeny consensus.The second part of this thesis is dedicated to machine learning problems which are shown to be closely related to ranking aggregation. The first one is dimensionality reduction for ranking data, for which we propose a mass-transportation approach to approximate any distribution on rankings by a distribution exhibiting a specific type of sparsity. The second one is the problem of predicting rankings with features, for which we investigated several methods. Our first proposal is to adapt piecewise constant methods to this problem, partitioning the feature space into regions and locally assigning as final label (a consensus ranking) to each region. Our second proposal is a structured prediction approach, relying on embedding maps for ranking data enjoying theoretical and computational advantages.

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<p>The overarching theme of this research is about environmental microplastic pollution, and how much various entities are willing to sacrifice economically to obtain a cleaner environment. To gauge such willingness, this research utilizes various economic measures that have been widely used, albeit with novel modifications. The focus of this research is on stated preferences about microplastic pollution. The topic of microplastics is still very novel, and market players on the demand side or on the supply side have yet to provide products that deal with this new pollutant. This lack has necessitated the need for stated preference research. This research delves into this novel environmental problem from various viewpoints.</p> <p> Chapter 1 of this research is about how much the US adult population is willing to sacrifice to obtain an environment that is less impacted by microplastic pollution. The results show that US adults in general possess a willingness to obtain an environment free from microplastics. However, a sizable minority of US adults do not show such willingness as well. Such results remained true even when information about microplastic pollution were provided to all respondents before preference elicitation. </p> <p> Chapter 2 investigates how much consumers in different countries will diverge about their willingness to pay for seafood that has less microplastic contamination. The countries chosen differed widely in their seafood consumption habits. Thus, it was hypothesized that such differences will lead to contrasts in their willingness to pay for less contaminated seafood. The hypothesis was found to be true but not in the way that was expected. The results show that frequent consumers of seafood had less willingness to pay when compared to others, although in whole all consumers showed willingness to avoid microplastics in their seafood. </p> <p> Chapter 3 makes use of the same data as Chapter 2 but looks at possible reasons for the disparity in responses besides factors explored in Chapter 2. Chapter 3 focuses on the cultural differences to explain the differences in behavior. To do so, it utilizes the Value-Belief-Norm theory widely employed in past research but modifies it to account for a form of hypothetical bias. The research delves into the relationships between many factors of interest that affect environmentally friendly consumption behavior and the findings show that a certain cultural tendency is central to such behavior, at least for microplastics. </p> <p> The research has done its best to research into the economic relationship between microplastic contamination of the environment and how much various individuals are willing to sacrifice to obtain an environment that is less impacted by such pollution. The findings here show that there is room for improvement in the way the microplastic pollution problem is being handled. However, in all settings the results show that a sizable majority want to be less impacted by microplastic pollution, a key takeaway for all interested parties.</p>

Discovery of Novel Serum Biomarkers for Diagnosing and Staging Alzheimer’s DiseaseDipti Jigar ShahDepartment of Chemistry and Biochemistry, BYUDoctor of PhilosophyAlzheimer’s disease (AD) is an untreatable neurologic disease affecting more than 5 million Americans, most over 60 years of age. Protein plaques and neurofibrillary tangles typify AD brain pathology and are thought to cause the progressive dementia and brain shrinkage observed in AD. Currently there are no methods to diagnose the disease at a time before damage becomes irreversible.Biochemical tests for AD using cerebrospinal fluid analysis or neuroimaging are not yet sufficiently sensitive and specific, and they are invasive. This points to a need for a more easily applied and more sensitive diagnostic test. Although the gross anatomical changes are localized to the brain, AD is likely to involve changes throughout the body. As a result of this, changes in the abundance of certain biomolecules present in the circulation system are likely to occur. Consequently, a serum proteomics approach able to measure such changes, when applied to AD, would likely find quantitative changes in relevant molecules that can help diagnose the disease correctly, ideally early in the disease process. The goal of this work was to discover and validate novel diagnostic serum biomarkers for AD. For biomarker discovery and validation, we used a novel serum proteomics approach involving reversed phase capillary-liquid chromatography-electrospray ionization-quadrupole-time of flight mass spectrometry. Our samples were protein depleted, which helped us survey low molecular weight species in the serum without ion suppression from larger proteins like albumin. We were able to observe more than 8000 molecular species in a single run. The overall project was comprised of four studies: (i) discovery of novel potential serum AD markers, (ii) blinded validation of diagnostically promising biomarkers found in the initial study, with their further chemical identification, (iii) exploring gender-based serum AD biomarkers, and (v) discovery of biomarkers that distinguish early versus moderate stage AD. In the first study, the approach found 38 significant (p < 0.05) biomarkers and 21 near significant (p = 0.05 to 0.099) biomarkers. On using the forward selection approach, we built multi-marker panels with specificities and sensitivities higher than 80%.The second study reports on a blinded validation study that was performed on a new set of serum samples. We focused on the 13 most promising AD biomarkers found as part of the initial study. We successfully validated 4 of these biomarkers that showed highly significant statistical p-values. As part of this study, research was conducted to identify these 4 biomarkers, which was accomplished using tandem mass spectrometry with fragmentation experiments. The third study used data from the initial study but looked at gender specific biomarkers. We found 31 significant and near significant serum AD biomarkers for women, 16 for men, and 25 that were gender independent. Multi-marker panels of AD biomarkers for women or men had sensitivities of >60% and specificities >85%.In the fourth study, cases with moderate AD were compared to cases with very mild or mild AD to find novel biomarkers that could be used for staging. We found 44 significant and near significant biomarkers that were quantitatively different between mild and severe AD. In conclusion, we were successful in accomplishing the goal of this work of finding, validating and identifying novel serum biomarkers that diagnose AD.

Science and technology are constantly transforming our day-to-day living. Science education has become of vital importance to prepare learners for this everchanging world. Unfortunately, science education in South Africa is hampered by under-qualified and inexperienced teachers. Textbooks of good quality can assist teachers and learners and facilitate the development of science teachers. For this reason thorough assessment of textbooks is needed to inform the selection of good textbooks. An investigation revealed that the available textbook evaluation instruments are not suitable for the evaluation of the physical science textbooks in the South African context. An instrument is needed that focusses on science education textbooks and which prescribes the criteria, weights, evaluation procedure and rating scheme that can ensure justifiable, transparent, reliable and valid evaluation results. This study utilised elements from the Analytic Hierarchy Process (AHP) to develop such an instrument and verified the reliability and validity of the instrument’s evaluation results. Development of the Instrument for the Evaluation of Science Education Textbooks started with the formulation of criteria. Characteristics that influence the quality of textbooks were identified from literature, existing evaluation instruments and stakeholders’ concerns. In accordance with the AHP, these characteristics or criteria were divided into categories or branches to give a hierarchical structure. Subject experts verified the content validity of the hierarchy. Expert science teachers compared the importance of different criteria. The data were used to derive weights for the different criteria with the Expert Choice computer application. A rubric was formulated to act as rating-scheme and score sheet. During the textbook evaluation process the ratings were transferred to a spreadsheet that computed the scores for the quality of a textbook as a whole as well as for the different categories. The instrument was tested on small scale, adjusted and then applied on a larger scale. The results of different analysts were compared to verify the reliability of the instrument. Triangulation with the opinions of teachers who have used the textbooks confirmed the validity of the evaluation results obtained with the instrument. Future investigations on the evaluation instrument can include the use of different rating scales and limiting of criteria. / Thesis (M. Ed. (Didactics))

Les comparaisons temporelles sont essentielles pour s’évaluer. Plusieurs études se sont intéressées aux conséquences négatives d’être insatisfait à la suite de comparaisons temporelles désavantageuses (c.-à.-d., à la privation relative). Peu d’étude a toutefois examiné l’évolution de ce sentiment d’insatisfaction. Le présent mémoire propose que ressentir différents niveaux d’insatisfaction au fil du temps, soit une trajectoire instable d’insatisfaction, affecte négativement le bien-être psychologique. Trois études expérimentales ont été menées. Les résultats révèlent que percevoir une trajectoire instable d’insatisfaction affecte négativement le bien-être psychologique. Une quatrième étude corrélationnelle a été menée au Kirghizstan afin d’examiner si les perceptions d’insatisfaction et d’instabilité mesurées à fil de l’histoire d’un groupe sont associées au bien-être psychologique lors de changements sociaux. Les résultats suggèrent que percevoir un haut niveau d’instabilité et d’insatisfaction au fil du temps est associé négativement au bien-être. Les implications théoriques et méthodologiques sont discutées. / Temporal comparisons are essential for one’s self evaluation. Several studies have examined the negative consequences of being dissatisfied after unfavorable temporal comparisons (i.e., having a feeling of relative deprivation). However, few studies have examined how changes in relative deprivation affect well-being. The present master’s thesis proposes that feeling different levels of relative deprivation over time (i.e., an unstable trajectory of relative deprivation) negatively affects people’s well-being. Three experimental studies were conducted. Results showed that perceiving an unstable trajectory of relative deprivation negatively affects well-being. A fourth correlational study was conducted in Kyrgyzstan in order to examine whether perceptions of relative deprivation and instability measured retrospectively across a group’s history are associated with people’s well-being in times of social change. Results suggested that perceiving high instability and a high level of relative deprivation over time is negatively associated with well-being. The theoretical and methodological implications are discussed.

This doctoral thesis consists of five self-contained essays.Common themes that unify the essays are the conditions for innovative engagements and the effort to endogenize innovations into the explanation of profitability, productivity and growthin manufacturing and service production. The purpose is to explore the importance of innovation in explaining heterogeneity in the performance of firms. The traditional analysis of the relationship between research and developmentand productivity is extended and developed by using, on the onehand, firm-level data not previously available and, on theother, a modern state-of-the-art econometric framework. Essay I. Methods and results are reviewed and stylized facts presented regarding the return on innovation. The limitations of the data and methods used in mainstream literature are discussed. A set of firm-level observations recently made available and a multiple knowledge production function analysis have been used to clarify the role of innovation in explaining performance heterogeneity among manufacturing firms inSweden. Essay II. The relationships between innovation and productivity among manufacturing firms in Finland, Norway and Sweden are studied. The main purpose is to investigate the contributions of firm-level innovation in creating the large observed differences in aggregated productivity growth between Norway on the one hand and Finland and Sweden on the other. Essay III. The focus of this essay is threefold. One, since innovation has been found to be a major contributor to productivity growth in manufacturing, we seek to find whether there is any evidence for the notion that service industrie shave a lower propensity to be innovative or that they are less efficient in deriving benefits from innovations. Second, we consider what real productivity growth does, and what the measurement methods do to produce the reported weak growthrates in services. Third, given that intermediate services have been found to be one of the fastest growing input factors inmanufacturing, largely reflecting the replacement of internally provided activities by externally produced outputs, we examine what the impact of outsourcing is on productivity growth in manufacturing. The essay brings a comparative perspective to these issues by analyzing the firm-level data on innovativeactivities and economic performance in knowledge-intensive manufacturing and service firms in Sweden. Essay IV.This essay investigates the sensitivity of estimated relationships between innovation and firm performance. The essay compares the sensitivity of results with regards to different types of models, estimation methods, measures of firm performance, classification of firms, type of innovations and data sources. The analyses are performed on both the level and growth rate of firm performance, and theinfluence of outliers is explored. Essay V. The role of capital structure and external financing in innovation and production is studied. Results from different model specifications are explored. A preferred dynamic model with flexible adjustment is used for an inter-country and an intra-country comparison of the determinants of the optimal mix between debt and equity as wellas the rate of change towards an optimal capital structure. / <p>QC 20100526</p>

The thesis of this study is that Classical studies at the University of Malawi, Chancellor College, has been taught with almost no reference to its African context, yet the Classical world, as Ogilvie (1979:2) observed ‘is far removed in time, geography, and philosophy from the world of Africa'. Classics in Malawi is currently taught as in the West, with which it has immediate ties, but if there are to be meaningful gains on the part of students learning Classics in Malawi, we need to contextualise its teaching. The purpose of this study was to identify ways in which Classics teaching at undergraduate level in Malawi might be strengthened in order to make the learning of Classics more meaningful and relevant to the Malawian context, by bridging the gaps between Classical Antiquity and African cultures. The comparative approaches explored will facilitate revision of the University of Malawi Classical Studies curriculum to fulfil the needs and interests of Malawians with the main purpose of contextualising Classical Studies in Malawi. The thesis consists of five chapters which deal with issues relating to Classics teaching in Malawi, namely: the evolution of Classical Studies in Malawi and its challenges; the need to change with the times; views of Latin/Classics teachers about Latin teaching at secondary level; attitudes and perceptions of undergraduate Classics students at Chancellor College to Classics, their perceptions about skills and Classics teaching in general; and views from Classicists from other universities on Classics teaching in general. The main comparative element in the thesis draws on analysis of similar issues in a wide variety of other institutions, including in the UK, the USA, Asia and Africa. Literature relating to Classics pedagogy and Comparative Education approaches, specifically Bereday's Model, has been reviewed. In addition, Classical Reception theory and Social Constructivism theory, particularly with regard to pedagogy, have been surveyed. The study used purposive sampling. Five types of samples and their corresponding data capturing instruments were used, broken down in the following categories: two types of interviews (one involving Malawian Latin or Classics teachers at secondary level, and the other universities' Classics lecturers); review of various documents of international universities' Classics programmes; lecture observations for Classics; and student questionnaire interviews administered to University of Malawi Classics students. The research was a mixed-method design, combining both quantitative and qualitative data analysis, but overall, the study was more qualitative than quantitative. Quantitative data were analysed using descriptive statistics and qualitative data were analysed using the thematic analysis method. These analyses were followed by discussions of the findings of both quantitative and qualitative data. The major conclusions and implications of the study point to the need for a curriculum review of all Classics courses to ensure that Classics becomes more relevant in the Malawian context.

L’objet de la thèse réside dans l’analyse des relations entre confiance, cohésion sociale et performance. A partir d’une analyse critique de l’usage de la notion de confiance en économie, la thèse propose une réflexion conceptuelle débouchant sur une conception tridimensionnelle de la confiance, une confiance stratégique, une confiance personnelle et une confiance généralisée. A partir d’une analyse en composantes principales et des données de la cinquième vague du World Values Survey, nous proposons une traduction empirique de cette notion. Les indicateurs ainsi construits sont utilisés pour réaliser une analyse économétrique des déterminants de la confiance en termes des caractéristiques personnelles et des facteurs tels que l’appartenance religieuse et l’engagement civique et politique. Au regard de ces indicateurs la thèse propose une analyse de la confiance en France au regard des autres pays de l’OCDE et une typologie pays fonction des articulations entre les trois types de confiance et leurs différents niveaux. Ensuite nous proposons une conceptualisation de la notion de cohésion sociale en termes de participation civique et politique, confiance systémique et interindividuelle et respect de la diversité. A partir d’une classification ascendante hiérarchique nous proposons une typologie « cohésion sociale » sur les pays de l’OCDE. Pour finir nous testons économétriquement l’effet des divers indicateurs de confiance et de cohésion sociale sur la performance économique et sociale / The aim of the thesis is the analysis of the relationship between trust, social cohesion and performance. Through a critical analysis of the use of the notion of trust in economics, the thesis proposes a conceptual development leading to a three-dimensional conception of trust, a strategic trust, a personal trust and a generalized trust. Using a principal component analysis and processing data from the fifth wave of World Values Survey, we propose an empirical translation of this concept. The indicators we have constructed are used to perform an econometric analysis of the determinants of trust in terms of personal characteristics and factors such as religious and civic and political engagement. Based on these indicators the thesis provides an analysis of confidence in France in comparison with other OECD countries and a typology based on networks between the three types of trust and their different levels. Finally we propose a conceptualization of the notion of social cohesion in terms of civic and political participation, trust and inter-systemic and respect for diversity. From a hierarchical ascending classification we propose a typology of "social cohesion" of the OECD countries. Finally we test econometrically the effect of various indicators of trust and social cohesion on the economic and social performance

La présente recherche s’inscrit dans un contexte d’emploi particulier, celui de l’intermittence du spectacle qui est un mode d’affiliation spécifique au régime de l’assurance-chômage. Si, au départ, ce régime est avantageux dans la mesure où il s’adapte à des métiers qui ne permettent pas de travailler de manière continue par la compensation, sous forme d’indemnités-chômage, des aléas de la vie professionnelle, les réformes successives, dont il a fait l’objet, et notamment le protocole de 2003, ont profondément modifié les règles qui prévalaient jusqu’alors en matière de gestion temporelle de l’emploi et de l’activité de travail pour les techniciens et les artistes du spectacle, introduisant un principe de « double incertitude ».L’objectif de cette thèse est de contribuer à la production des connaissances sur la manière dont se construisent les Perspectives Temporelles dans des contextes socio-professionnels marqués par une forte instabilité et une incertitude accrue, en appréhendant le rôle des processus comparatifs mis en œuvre par les individus dans le sens qu’ils accordent à leurs expériences.Nous avons rencontrés 20 intermittents du spectacle, dont 10 techniciens du spectacle (annexe 8) et 10 artistes (annexe 10). Selon une approche essentiellement qualitative (Delory-Momberger, 2013), nous avons effectué des entretiens semi-directifs de type « récits de vie » (Bertaux, 1984). Les données recueillies ont fait l’objet d’une double analyse lexicométrique et phénoménologique. Nos résultats montrent que la relation existant entre les modalités d’inscription dans une situation plus ou moins précarisée et la construction des perspectives temporelles est médiatisée par des processus de comparaison sociale mis en œuvre par les individus dans leurs différentes sphères de vie et dont l’issue va contribuer à l’orientation (ou à la réorientation) de ces perspectives temporelles et au vécu de cette situation. / This research deals with a particular context of employment: occasional work in the entertainment industry, which is a mode of affiliation which is specific to the system of unemployment insurance. At first, this system was advantageous, insofar as it was compatible with jobs which cannot provide continuous work - thanks to the compensation of the hazards of work life through unemployment indemnities. However, the succeeding reforms - especially the 2003 protocol – deeply changed the regulations which had up to then prevailed in the time management of jobs and professional activities for technicians and artists in the entertainment industry, by initiating a principle of « double uncertainty ».The aim of this dissertation is to contribute to widen the knowledge about the way Temporal Perspectives develop in socio-professional contexts amid which heavy instability and increased uncertainty occur. In order to do so, this paper attempts to grasp the role of the comparative processes carried out by individuals in the meaning they attribute to their life experiences.We have met with 20 occasional entertainment workers, among whom 10 entertainment technicians (appendix 8) and 10 artists (appendix 10). Following a thoroughly qualitative approach (Delory-Momberger, 2013), we have carried out semi-guiding interviews in form of « life narratives » (Bertaux, 1884). The data gathered was submitted to a double analysis: lexicometric and phenomenological.The results show that the connection found between the ways individuals join into a situation more or less unsecured and the creation of temporal perspectives is mediated through social comparison processes carried out by individuals in the different spheres of their lives. Subsequently, the outcome of these processes will help direct (or redirect) these temporal perspectives and contribute to their life experience.