I present the results of two studies designed to explore how Expectation Violation Theory may explain biases in performance ratings. Study 1 examines how pre-hire information biases on-the-job ratings of task performance. Study 2 replicates the findings of Study 1 for on-the-job ratings of OCB performance. Results of these studies suggest that expectations violations do occur when on-the-job performance is either higher or lower than suggested by pre-hire information. However, first impressions of the employee appear to bias performance ratings of both task and OCB performance rather than expectation violations. Findings suggest applicants that make positive first impressions are rated higher on both OCB and task performance than equivalently performing co-workers who make less favorable first impressions.

We investigate several problems in relativity and particle physics where symmetries play a central role; in all cases geometric properties of Lie groups and their quotients are related to physical effects. The first part is concerned with symmetries in gravity. We apply the theory of Lie group deformations to isometry groups of exact solutions in general relativity, relating the algebraic properties of these groups to physical properties of the spacetimes. We then make group deformation local, generalising deformed special relativity (DSR) by describing gravity as a gauge theory of the de Sitter group. We find that in our construction Minkowski space has a connection with torsion; physical effects of torsion seem to rule out the proposed framework as a viable theory. A third chapter discusses a formulation of gravity as a topological BF theory with added linear constraints that reduce the symmetries of the topological theory to those of general relativity. We discretise our constructions and compare to a similar construction by Plebanski which uses quadratic constraints. In the second part we study CP violation in the electroweak sector of the standard model and certain extensions of it. We quantify fine-tuning in the observed magnitude of CP violation by determining a natural measure on the space of CKM matrices, a double quotient of SU(3), introducing different possible choices and comparing their predictions for CP violation. While one generically faces a fine-tuning problem, in the standard model the problem is removed by a measure that incorporates the observed quark masses, which suggests a close relation between a mass hierarchy and suppression of CP violation. Going beyond the standard model by adding a left-right symmetry spoils the result, leaving us to conclude that such additional symmetries appear less natural.

Le sujet de cette thèse porte sur l’étude de la désintégration faible du baryon beau Λb → Λ J/Ψ avec le détecteur LHCb. Cette étude offre la possibilité de tester, d’une part, la validité de la symétrie CP dans le secteur baryonique et, d’autre part, celle de la symétrie de renversement du temps T dont les preuves expérimentales de sa violation sont limitées. L’accent est mis sur la mesure des composantes des vecteurs-polarisations du Λb et des résonances intermédiaires Λ et J/Ψ, dont certaines du type ”T-odd” (impaires par T) représentent un signe clair de violation directe de T. Le développement d’un modèle phénoménologique des désintégrations Λb → Λ J/Ψ dans le cadre du formalisme d’hélicité de Jacob-Wick et de Jackson conduit aux calculs de distributions angulaires qui permettent de déduire les valeurs des composantes des vecteurs-polarisations. Une étude approfondie de la reconstruction et de la sélection des données enregistrées par LHCb en 2011 et 2012 est exposée, ainsi qu’une simulation Monte-Carlo complète. La compatibilité entre les valeurs mesurées des vecteurs-polarisation du Λb et du Λ ̄b implique l’absence de violation de CP. La violation directe de la symétrie T n’a pas non plus été observée dans les désintégrations hadroniques du Λb (Λ ̄b). Sur un autre plan, les premières mesures des polarisations longitudinales du Λb et du Λ ̄b ainsi que de la polarisation longitudinale du méson-vecteur J/Ψ ont été réalisées dans le cadre de ce travail. / This thesis subject focuses on the study of the weak decay of the beauty baryon Λb →Λ J/Ψ with the LHCb detector. Firstly, it offers the opportunity to test the validity of the CP symmetry in the baryon sector and, secondly, the one of time-reversal symmetry T whose experimental evidence is tiny. Emphasis is put on the measurement of the components of the polarization-vectors of the Λb and the ones of the intermediate resonances Λ and J/Ψ, whose some components exhibit a clear sign of direct T violation. The development of a phenomenological model of the Λb → Λ J/Ψ decay in the framework of the helicity formalism of Jacob-Wick and Jackson leads to the calculations of the angular distributions which allow to deduce the values of the polarization vector components. A thorough study of the reconstruction and the selection of the data recorded by LHCb in 2011 and 2012 is exposed, as well as a full Monte Carlo simulation. The compatibility between the measured values of the polarization-vector of Λb and Λ ̄b implies the absence of CP violation. The direct violation of the T symmetry has not been observed in the hadronic decays of Λb ( Λ ̄b). On another side, first measurements of the longitudinal polarization of Λb and of Λ ̄b well as the longitudinal polarization of the vector-meson J/Ψ have been performed in the context of this work.

This dissertation considers the entire process originated by corporate events that impact the environment and the society (ES events). Using a rich hand-collected dataset with 1139 chronological incidents originating from negative corporate social responsibility (CSR)-related events, it explores stock market reactions to each stage within a chain of successive events triggered by negative ES events, including the recurrent, follow-up (either favorable or unfavorable), as well as companies’ response events. We find that the investors respond strongly negatively to negative events (origin, negative subsequent, and negative responses) and strongly positively to positive events (positive subsequent and positive responses). We also find that investors react more negatively to the negative subsequent and recurrent events, as well as company negative responses when they occur sooner after the origin events, whereas promptness of positive subsequent events and positive responses heighten the favorable market reaction. The study also reveals the presence of expectancy violation as investors of high-CSR firm react more negatively to the negative events. In addition, it provides observations suggesting that: (1) investors do not regard positive responses as agency-motivated events, instead they are more concerned about the availability of financial resources when a firm makes remedial responses to a negative ES event; and (2) the market cares about CSR events not solely due to their financial implications, but also because it considers socially responsible operations as a value-enhancing corporate duty.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18063号 / 理博第3941号 / 新制||理||1568(附属図書館) / 30921 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 中家 剛, 准教授 市川 温子, 教授 鶴 剛 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

The purpose of this study was to determine whether a discrepancy existed between the premigration expectations and postmigration experiences of Hispanic immigrants with regard to their quality of life in the United States in communication, social, economic, and educational domains, and whether the discrepancy is correlated with acculturative stress. Acculturative stress refers to the stress that is related to the demands and pressure to adapt to a new culture. Indicators of acculturative stress include feelings of isolation due to inadequate social resources, apprehension at having to adapt to a new environment, angst over an inability to communicate in English, and worry over limited financial resources (Hovey, 1999). The current study analyzed data collected from a sample of 61 foreign-born individuals of Latin ancestry who came to the United States as an adult and have lived here for less than five (5) years. The findings indicate that violated expectations are correlated with acculturative stress more so than demographic variables, personality constructs and common sources of stress. Additionally, discrepancies between premigration expectations and postmigration experiences were found to be better predictors of acculturative stress than postmigration experiences alone.

Plusieurs observations montrent une asymétrie baryons-antibaryons dans l'Univers. La principale théorie expliquant cette asymétrie est la baryogenèse qui requiert les trois conditions de Sakharov : la non-conservation du nombre baryonique, la présence de violation CP et des interactions entre particules hors de l'équilibre thermique. La baryogenèse nécessite de considérer de la physique au-delà du Modèle Standard (MS), car le MS suppose généralement une asymétrie baryonique trop petite. La baryogenèse peut être obtenue à partir de la leptogenèse, la théorie équivalente pour les leptons. De nouvelles particules et interactions impliquant des leptons généreraient une asymétrie leptonique (AL) mesurable au LHC qui serait transférable au secteur baryonique. L'ajout de neutrinos de chiralité droite (RH) au MS est un choix naturel pour expliquer l'origine de la masse des neutrinos et l'existence d'une AL, et donc d'une asymétrie baryonique. Le projet aborde certains processus détectables au LHC impliquant la désintégration de bosons W en neutrinos RH. Ces processus peuvent violer le nombre leptonique et la symétrie CP. Des facteurs d'asymétrie CP sont calculés et permettent de mesurer des invariants CP. Les invariants CP dépendent des paramètres du modèle et quantifient la violation CP. Ces invariants CP apparaissent dans les équations de Boltzmann qui décrivent l'évolution de l'AL. La résolution de ces équations permet de calculer le ratio du nombre de baryons sur le nombre de photons dans l'Univers. L'identification des invariants CP qui décrivent l'AL permet de tester les modèles de la leptogenèse par la mesure de processus impliquant de la violation CP au LHC. Pour répondre à ces objectifs, un scénario de leptogenèse résonante a été testé. Les résultats obtenus montrent que les invariants CP nécessaires pour reproduire l'asymétrie baryonique sont trop petits pour être mesurés au LHC. De futures recherches pourraient s'intéresser à d'autres modèles menant à un signal observable au LHC.

[pt] A partir do século passado descobrimos a existência de antipartículas e, desde então, a busca por entender a assimetria entre partícula e antipartículas tem sido um forte campo de pesquisa na física. Dentre as condições que possibilitam a assimetria matéria-antimatéria no Universo, está o fenômeno da Violação de Carga-Paridade (VCP). Devido à ela observamos diferenças entre os processos decaimento de uma partícula e sua antipartícula. Tal fenômeno tem efeitos importantes para mésons formados pelos quarks b ou s, porém as predições deste efeito para o setor de charme são muito pequenas, com assimetrias de CP em torno da ordem de 10−3 ou menores. De fato, apenas recentemente a VCP foi observada em decaimentos de 2 corpos de mésons D0. Esta dissertação discute duas estratégias na busca por VCP no canal D+ → π−π+π+ utilizando dados do experimento LHCb durante o Run II. O método de busca por VCP, método Mirandizing, consiste em computar estatisticamente as populações de D+ e D− em intervalos do espaço de fase bidimensional, calculando a significância da diferença dessas populações. Para amostras de grande estatística, como é o nosso caso, o objetivo final é aplicar um método alternativo que consiste em obter o número das populações através de ajustes de massa para cada intervalo. Este trabalho tem como objetivo realizar a validação do método. Nossa estratégia é realizar os procedimentos dividindo a amostra de forma aleatória em duas sub-amostras e não separando nas amostras de D+ e D−. O que se espera, então, são resultados que demonstrem compatibilidade estatística entre as duas amostras. Além dessa validação utilizando os dados, vamos, também, realizar o mesmo procedimento em 100 pseudo-experimentos. Adicionalmente, realizamos os estudos de sensibilidade a fim de verificar em quais possíveis cenários a VCP poderia ser observada nesse canal, dado o tamanho da amostra total. Para este estudo, obteremos o número das populações através da contagem direta (método Mirandizing) dos eventos do espaço de fase dentro da região de massa de maior com maior concentração de eventos de sinal. / [en] Last century we discovered the existence of antiparticles, and since then the search to understand the asymmetry between particles and antiparticles has been a strong field of research in physics. Among the conditions that make matter-antimatter asymmetry possible in the Universe is the Charge-Parity Violation (CPV) phenomenon. Due to it we observe differences between the decay processes of a particle and its antiparticle. Such a phenomenon has important effects for mesons formed by b or s quarks, but the predictions of this effect for the charm sector are very small, with CP asymmetries around the order of 10−3 or smaller. In fact only recently has CPV been observed in 2-body decays of D0 mesons. This dissertation presents the validation of strategies in the search for CPV in the D+ → π−π+π+ channel using data from the LHCb experiment during Run II. The CPV search method, the so-called Mirandizing method, consists of statistically computing the populations of D+ and D− in intervals of the two-dimensional phase space, obtaining the significance of the difference of these populations. For large statistical samples, as is our case, the ultimate goal is to apply an alternative method by obtaining the number of the populations through mass fits for each interval. This work aims to perform the validation of the method. Our strategy is to perform the procedure by dividing the sample randomly into two subsamples, but not separating into the D+ and D− samples. What is expected, then, is that the results demonstrate statistical compatibility between the two samples. In addition to this validation using data, we will also perform the same procedure on 100 pseudo-experiments. Finally, we perform sensitivity studies in order to verify the possible scenarios in which CPV could be observed in this channel, given the total sample size. For this study, we will obtain the number of the populations by directly counting the phase space events (Mirandizing) within the mass region with the highest concentration of signal events.

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