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Den verkställande direktörens ersättning : En jämförelse mellan fastighets-, finans och läkemedelsbranschenBasmaci Talita, Awabdeh Maikel January 2016 (has links)
Purpose: The study aims to show if there is a significant relationship between the CEOs recompense and the size of the company between the industries. The goal is to compare the size of a company with the variable that shows performance and which of them who has the strongest connection to the recompense. Method: The essay stands on a quantitative approach where secondary data has been gathered from the year of 2015 annual reports. The population includes all the Swedish companies in the real estate-, finance- and pharmaceutical industry that are listed on the stock exchange. Selection has been made on 30 of these companies, 10 in each industry. With the statistical analyses the methods that have been used are multiple regression model and correlation analysis. Results: The results show that the company that paid the highest recompense in the real estate industry was Kungsleden. The company in the finance industry was Kinnevik and in the pharmaceutical industry it was Pfizer. Conclusion: After analyzing the result the conclusion can be made that there is a significant relationship between the CEOs recompense and the size of the company only in the real estate industry. When comparing the variable that dictates the size of the company (net sales) and the performance variable (MVA), the conclusion that can be made is that MVA has a stronger connection to the CEOs total recompense in the pharmaceutical industry in relation to the other industries. Within the finance industry there was no significant relationship with the CEOs recompense and the selected variables.
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Spatial analysis of exposure coefficients with applications to stomach cancerMartinho, Maria January 2007 (has links)
Earlier ecological studies on the relation between H. pylori infection and stomach cancer have considered that the relation between these two variables, as estimated by the exposure coefficient, is constant. However, there is evidence to suggest that this relation changes geographically due to differences in strains of H. pylori. Since the prevalence of H. pylori varies with socio-economic status, the association between the latter and stomach cancer mortality may also vary geographically. This thesis studies stomach cancer by taking into account the geographical variability of the exposure coefficients. The study proposes the use of regression mixtures, clustering models and spatially varying regressions for the study of varying exposure coefficients. The effect of transformations of variables in these models appears to have been little considered. We provide new necessary conditions for invariance under transformations of variables for mixed effect models in general, and for the proposed models in particular. In addition, we show that varying exposure coefficients may induce a varying baseline risk. The regression mixtures and the clustering model are applied to a data set on stomach cancer incidence and H. pylori prevalence in 57 countries worldwide. We extend the clustering model to reflect any distance measure between the geographical units, including the Euclidean distance, in the formation of clusters. We also show that the clustering model performs better than the regression mixture model when the aim is to identify connected clusters and the observations present large variance. The results obtained with the clustering model supported the existence of three clusters where the interaction between the human and H. pylori populations have similar characteristics. Spatially varying regressions are applied to a data set of areal death counts of stomach cancer and spending power in 275 counties in continental Portugal. We provide an original strategy for implementing multivectorial intrinsic autoregressions as the distribution for the random effects. The results obtained with the application of this methodology were consistent with a varying exposure coefficient of spending power.
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A Sensitivity Analysis of Cross-Country Growth Regressions: Is 1990-2010 Different?Kiwan, Rami 12 1900 (has links)
Cet article étudie la sensibilité des estimations de certaines variables explicatives de la croissance économique dans des régressions en coupe transversale sur un ensemble de pays. Il applique un modèle modifié de l’analyse de sensibilité de Leamer (1983, 1985). Mes résultats confirment la conclusion de Levine and Renelt (1992), toutefois, je montre que plus de variables sont solidement corrélées à la croissance économique. Entre 1990-2010, je trouve que huit sur vingt cinq variables ont des coefficients significatifs et sont solidement corrélées à la croissance de long terme, notamment, les parts de l’investissement et des dépenses étatiques dans le PIB, la primauté du droit et une variable dichotomique pour les pays subsahariens. Je trouve aussi une preuve empirique solide de l'hypothèse de la convergence conditionnelle, ce qui est cohérent avec le modèle de croissance néoclassique. / This paper examines the robustness of explanatory variables in cross-country growth regressions. It employs a variant of Leamer’s (1983, 1985) extreme-bounds analysis. My results confirm Levine and Renelt’s (1992) conclusion, but identify more variables to be robustly correlated with economic growth. Of 25 explanatory variables tested, I find 8 to be significantly and robustly correlated with long-term growth over the 1990-2010 period. The strongest evidence is for the investment ratio, government consumption share in GDP, the rule of law, and the Sub-Saharan dummy. I also find strong empirical evidence for conditional convergence, which is consistent with the neoclassical growth model.
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Antioxidants as Risk Factors for Gingival BleedingBahng, Hee-Jeong 01 January 2004 (has links)
Background: Studies of gingival bleeding and the effects of antioxidants on extracellular matrix and immunologic and inflammatory responses provide a rationale for hypothesizing that antioxidants reduce the risk for gingival bleeding.Methods: This study evaluated the role of antioxidants as contributing risk factors for gingival bleeding utilizing the Third National Health and Nutrition Examination Survey (NAHNES III). A sample of 18,825 adults (20 to ≥ 90 years of age), with dental measurement and assessment of serum levels of antioxidants were included in the study. Gingival bleeding was defined as those who had more than 30 percent of gingival bleeding in 28 sites examined. SPSS version 11.0 software and Epi-info 2000 were used to perform the statistical analysis.Results: Using multiple logistic regression in five separate antioxidants, the study showed an association between increased plasma levels of vitamin C (ascorbic acid) and decreased risk for gingival bleeding (OR= 0.33; 95% CI 0.15 to 0.72). An inverse relationship was also found between gingival bleeding and serum levels of beta carotene (OR=1.93; 95% CI 1.05 to 3.54). However, negative association was found between gingival bleeding and vitamin A (OR=2.60; 95% CI 1.04 to 6.50). No statistically significant association was observed between gingival bleeding and serum levels in vitamin E (alpha tocopherol) and selenium.Conclusion: Antioxidants, vitamin C, vitamin A, and beta carotene, were significant risk factors for gingival bleeding. This should be emphasized for improving the oral health of the U.S. adult population.
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Caractérisation de l'environnement sonore urbain : Proposition de nouveaux indicateurs de qualité / Characterization of the urban soundscape : with new indicators of qualityBrocolini, Laurent 13 December 2012 (has links)
A l'heure actuelle, les seuls moyens d'informer les usagers de la ville de l'environnement sonore dans lequel ils vivent consistent en des indicateurs de niveaux sonores moyens et annuels obtenus par modélisation acoustique des principales infrastructures de transports. Or, ces indicateurs sont difficilement compris et de ce fait mal interprétés par les usagers de la ville car ils ne reflètent pas la signification des bruits perçus et la diversité des situations que les citadins rencontrent. Le but de ce travail de recherche est donc d'analyser la façon dont les usagers de la ville perçoivent le paysage sonore urbain afin de définir des indicateurs de qualité sonore qui pourront être à terme intégrés dans une représentation territoriale cartographique. Pour ce faire, il a tout d'abord été nécessaire de s'attacher à déterminer un pas temporel et spatial de mesure permettant de caractériser des ambiances urbaines d'un point de vue acoustique. A partir d'enregistrements longue durée (trois mois environs) en six points fixes à Paris, il a été possible de déterminer à travers des classifications ascendantes hiérarchiques de Ward associées à des cartes auto-organisatrices de Kohonen qu'une durée de dix minutes semble dans la plupart des cas être suffisante pour caractériser différentes ambiances sonores. Grâce aux mêmes méthodes de classification, l'analyse du maillage spatial a permis de définir quatre zones homogènes qui correspondent (1) au parc, (2) au boulevard, (3) à la rue piétonne puis (4) une zone que l'on qualifiera de zone de transition. La suite de l'étude s'est attachée à construire des modèles de prédiction de la qualité sonore. A partir d'enquêtes de terrain réalisées à Paris et à Lyon, il a été possible d'établir des modèles à la fois locaux (caractérisant le lieu même où le questionnaire a été évalué) et globaux basés d'une part sur des régressions linéaires multiples et d'autre part sur des réseaux de neurones artificiels. La comparaison de ces deux types de modèles a permis entre autre de mettre en évidence l'apport des réseaux de neurones artificiels devant les régressions linéaires multiples en termes de prédiction. Par ailleurs il est ressorti de ces modèles l'importance de variables telles que le silence, l'agrément visuel ou encore la présence de sources sonores particulières comme les véhicules légers pour expliquer la qualité sonore de l'environnement. / At present, the only ways to inform city dwellers about the sound environment in which they live are annual and average sound level indicators using acoustic modeling of main transport infrastructure. However, these indicators are difficult to understand and therefore misinterpreted by city dwellers because they do not reflect the significance of perceived noise and the diversity of the situations. The aim of this research is therefore to analyze how the city dwellers perceive the urban soundscape in order to characterize sound quality indicators which can be used into mapping. To do this, it was first of all necessary to determine a temporal and spatial resolution to characterize urban environment from an acoustic point of view. From long period recordings (almost three months) at six locations in Paris it was possible to determine through hierarchical ascendant Ward classifications combined with self-organizing Kohonen maps that duration of ten minutes for measurements seems to be enough to characterize in most cases different acoustic environments. Thanks to the same classification methods, spatial study made it possible to define four homogeneous areas which correspond (1) to the park, (2) to the boulevard, (3) to the pedestrian street and (4) to an area which can be considered as a transition one. Then this study focused on building sound quality predictive models. Thanks to field surveys in Paris and Lyon, it was possible to establish local models (characterizing the location where the questionnaire has been evaluated) and overall models based on one hand on multiple linear regressions and on the other hand on artificial neural networks. The comparison of both models highlighted the advantages of artificial neural networks compared to multiple linear regressions in terms of prediction. Moreover, according to these models, variables such as silence, the visual pleasantness or even the presence of specific sound sources as light vehicles explain the sound quality of the environment.
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Meziodvětvové mzdové rozdíly v České republice / Inter-industry Wage Differentials in the Czech RepublicHofman, Stanislav January 2013 (has links)
This thesis examines inter-industry wage differentials in the Czech Republic, using the European Union - Statistics on Income and Living (EU-SILC 2009) survey as our primary data source. Findings show that even after controlling for large number of workers and jobs characteristics wage differences based on industry affiliation still persist. The variation of the inter-industry wage differentials amounts to approximately 5 percent with the maximum wage level difference of 25 percent between the financial sector and agriculture. By applying two distinct methodologies we tested the hypothesis that the inter-industry wage differentials are actually caused by higher concentration of workers with better unmeasured abilities in higher-paying industries. Neither of the two methods rejected the unobserved ability hypothesis. Finally, our analysis also shows that the inter-industry wage differentials can be to a certain extent attributed to rent-sharing and different labour turnover costs across sectors.
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Communication Networks and Nutrition-sensitive Extension in Rural Kenya: Essays on Centrality, Network Effects and Technology AdoptionJäckering, Lisa 07 May 2018 (has links)
No description available.
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Um teste empírico para o modelo de precificação de ativos de capital baseado no consumo (CCAPM) na América LatinaKirch, Guilherme 29 March 2006 (has links)
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Previous issue date: 29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O propósito desta dissertação foi verificar se o Modelo de Precificação de Ativos de Capital baseado no Consumo (CCAPM) é consistente com os dados de quatro países latino-americanos: Brasil, Chile, Colômbia e México. Para alcançar este objetivo foi realizada uma regressão cross-sectional dos prêmios de risco médios sobre os betas de consumo de cada ativo em cada país analisado. Adicionalmente, de forma análoga a Lintner (1965) e Levy (1978), foi verificado se a variável ‘variâncias residuais’ mostrava-se estatisticamente significante nas regressões cross-sectional, o que seria inconsistente com o modelo. Os resultados empíricos, baseados em estimativas corrigidas para o problema dos erros nas variáveis, demonstram que há uma relação estatisticamente significativa entre os prêmios de risco médios e os betas de consumo nos países acima mencionados, com exceção do México. Apesar disto, o poder explicativo do modelo, dado pelo coeficiente de determinação R2 ajustado, foi muito baixo em todos os países. Quanto à v / The purpose of this thesis is to verify whether the Consumption based Capital Asset Pricing Model (CCAPM) is consistent with the data from four Latin-American countries: Brazil, Chile, Colombia, and Mexico. In order to reach this goal, a cross-sectional regression of the consumption betas on the mean excess returns of each asset is performed for each country analyzed. Also, similar to the studies of Lintner (1965) and Levy (1978), it is verified whether the variable ‘residual variance’ has statistical significance in the cross-sectional regressions, which would be inconsistent with the model. Empirical results showed that there is a statistical significant relationship between mean excess returns and consumption betas in the countries cited above, with exception of Mexico. Despite this, the explanatory power of the model, given by the adjusted coefficient of determination (R2), is very small in all countries. Concerning the variable ‘residual variance’, it is statistically significant for the Brazilian and Me
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Analyse des effets des pratiques managériales des dirigeants sur la performance à l'export : le cas des PME marocaines / Analysis of effects of management practices of the leaders on the export performance : the case of moroccan SMEsEl Makrini-Roche, Hind 17 October 2014 (has links)
L’objectif de cette recherche est d’analyser l’influence des pratiques managériales des dirigeants sur la performance à l’export des PME marocaines et de vérifier le rôle médiateur de la compétitivité, en se basant sur la théorie des ressources (RBV). L’approche quantitative est principalement utilisée dans cette recherche. Les analyses de régressions linéaires multiples utilisées sur un échantillon de 100 PME marocaines pour confirmer ou infirmer treize hypothèses de recherche, révèlent que seules certaines pratiques managériales sont stratégiques et conditionnent la performance à l’export, en développant des avantages compétitifs durables. L’étude a des implications utiles pour la recherche académique, les dirigeants et les politiques publiques, fournissant des lignes directrices et des repères utiles pour une performance supérieure à l’export. L’étude peut également être proposée dans l’enseignement supérieur afin d’informer le corps enseignant et les étudiants sur le contexte des PME. Cette recherche fait partie de l’une des rares études ayant mis en évidence le rôle médiateur de la compétitivité dans le contexte des pays en développement, en particulier dans les régions du Maghreb, où on note de rares références bibliographiques dans ce domaine.Des mesures aussi bien objectives que subjectives ont été utilisées pour mesurer la performance à l’export. Un certain nombre de limites doivent par ailleurs être prises en considération dans l’évaluation des résultats et leurs implications. Les contributions ne peuvent être généralisées que si les idées supplémentaires proposées résistent à l’épreuve du temps et de l’expérience. Une limite fondamentale est que les données analysées sont transversales plutôt que longitudinales. Le cadre développé dans cette recherche peut servir de point de départ à des recherches ultérieures. Celles-ci pourraient être enrichies en explorant les divers paramètres que nous n’avons pas envisagés tels quel la culture et le cycle de vie des produits et des entreprises. Il va de soi que ces facteurs pourraient revêtir une grande importance. / The purpose of this research is to analyze the impact of the managerial practices of managers on the export performance of Moroccan SMEs and to examine the mediating role of the competitiveness, based on the resource-based view (RBV) of a firmThe quantitative approach is particularly used in this study. The survey was conducted of 100 Moroccan SMEs. The multiple linear regressions employed to confirm or reject the hypotheses revealed that only certain managerial practices are strategic and can affect export performance by developing sustainable competitive advantage. The study has useful managerial implications for academics, practitioners and public policy makers, providing guidelines and interesting recommendations for a better export performance. The study can also be used in teaching. This is one of the few studies which highlighted the mediating role of the competitiveness in the context of a developing country, particularly in Maghreb regions, where the studies on this subject are rare.Both objective and subjective measures were used to measure export performance. However, the results presented in this work should be interpreted with caution, since the results have a number of limitations that should be taken into account when evaluating and generalizing their conclusions. Indeed, it is recommended that longitudinal and replication studies be undertaken, in order to ascertain the effect of the managerial practices on the export performance at different time and spatial frames. Future research should also include other important factors not analyzed in this study.
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Extreme temperature regimes during the cool season: recent observed behavior and low frequency mode modulationWestby, Rebecca Marie 18 November 2011 (has links)
During the boreal cool season, regional climate in the United States is strongly impacted by extreme temperature regimes (ETRs), including both cold air outbreaks (CAOs) and warm waves (WWs), which have significant impacts on energy consumption, agriculture, as well as the human population. Using NCEP/NCAR and MERRA reanalysis data, the statistical characteristics of ETRs over three distinct geographical regions are studied: the Midwest (MW), Northeast Megalopolis (NE), and Deep South (SE). The regional long-term variability in the frequency and amplitude of ETRs is examined, and the modulation of these ETRs by low frequency modes is quantified.
ETR behavior is characterized using three different metrics applied to both T and Twc: 1) the number of extreme cold/warm days, 2) a seasonal cumulative "impact factor", and 3) a peak normalized anomaly value. A trend analysis reveals a significant downward trend in SE WW events from 1949-2011. Otherwise, no significant trends are found for ETRs in any of the other regions. Thus, these results indicate that there has not been any significant reduction in either the amplitude or frequency of CAOs over the United States during the period of analysis. In fact, for the SE region, the recent winters of 2009/2010 and 2010/2011 both rank among the top 5 in terms of CAO metrics. In addition, strong interannual variability in ETRs is evident from 1949-2011 in each region. Linear regression analysis is then used to determine the associations between ETR metrics and the seasonal mean state of several low frequency modes, and it is found that ETRs tend to be modulated by certain low frequency modes. For instance, in the SE region, there is a significant association between ETRs and the phase of the North Atlantic (or Arctic) Oscillation (NAO/AO), the Pacific North American (PNA) pattern (for WWs only), the Pacific Decadal Oscillation (PDO) and the El Niño-Southern Oscillation (for WWs only). Over the MW region, WWs are modulated by the NAO/AO and PNA patterns, while in the NE region, the AO, NAO (for WWs only) and PDO (for WWs only) are implicated. In addition, it is found that there is an asymmetry between the low frequency mode modulation of CAOs and WWs. Multiple linear regression analysis is then used to quantify the relative roles of the various low frequency modes in explaining interannual variability in ETR metrics, and reveals that various combinations of low frequency modes can explain anywhere between 10% and 50% of the variance in the ETR metrics.
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