This dissertation consists of two chapters. Chapter 1 focuses on the barriers that diversifying companies could face and explore how barriers to entry differ across different types of entry. Chapter 2 turns the attention to the market competition among insurance companies that are already in a market and examines how product bundling impact insurers' market power. Chapter 1 proposes and estimates a multi-agent model of entry. The prior literature often treats the number of companies in a market as an exogenous measure of market structure. However, the number of companies is endogenously decided by the market structure and other participants. Thus, I propose a structural model of entry to address the endogenous entry decision. In addition, the estimations are conducted at each market-year level, therefore, it provides an opportunity to delineate the relative importance of barriers to entry across three dimensions: geographic, product, and time. I find that barriers to entry exist in the financial services industry, and can be quite substantial to the \textit{de novo} entrants. Overall, I find \textit{de novo} entrants are the ones most subject to barriers to entry across all markets. Expanding within a state is as costly as expanding within a product line. Upon further examination, I discover that product-specific knowledge, such as underwriting expertise, pricing schemes, and coverage designs, plays a critical role in a successful expansion. This information is also relatively more important than state-specific connections, such as how well the company knows its customers and connections with distribution channels. Among all product lines, I find that expertise in mortgage guaranty insurance creates the most barriers, and these barriers are most subject to impacts of the financial crisis. In Chapter 2, I turn the focus to the market competition \emph{within} a market and explore the impact of product bundling on market power. Product bundling is a popular way for companies to retain their customers and keep up with fast-changing market demand. In this chapter, I will specifically examine the impact of bundling on price elasticity for personal lines of insurance. Insurance demand estimation is well-explored in the literature because it is difficult to obtain individual-level data. I overcome this hurdle by using a random coefficients logit model, which incorporates flexible consumer preferences over companies' characteristics. The second difficulty in insurance demand estimation is that it is hard to find a good instrument for the endogenous price. Therefore, I propose a novel instrument, which exploits an idiosyncrasy in insurance tax laws for identification. I find that bundling, on average, can reduce consumers' price sensitivity. Thus, companies that can offer bundle-able products experience a less elastic demand and achieve market power. However, product bundling has differential impacts on the auto insurance and homeowners' insurance markets. Auto insurers that offer bundled packages experience less elastic demand in response to price increases. However, we do not observe similar patterns in the homeowners' insurance market, where doing so intensifies price elasticity. With a closer examination, we discover that the different valuation in homeowners is not driven by the financial ratings of insurers. This indicates that homeowners tend to value other characteristics, such as claims management and the quality of service, more than just price of the contract. / Business Administration/Risk Management and Insurance

A alvenaria estrutural vem sendo amplamente difundida em contexto nacional principalmente a partir da década de 90. Dentre as grandes vantagens do sistema construtivo podem ser citadas a economia de tempo e de material, além da redução do volume de resíduos. Para a segurança quanto ao uso da alvenaria, faz-se necessário o conhecimento do seu comportamento quando exposta a elevadas temperaturas em virtude da degradação das propriedades dos materiais, o que não é contemplado por normas nacionais. O uso de normas estrangeiras tem como referência propriedades e parâmetros dos materiais de suas respectivas abrangências. Em relação à modelagem numérica, esta é uma alternativa de grande eficiência e versatilidade em virtude dos elevados custos envolvidos nas análises experimentais e necessidade de infraestrutura adequada para os ensaios. O objetivo principal deste trabalho foi obter modelos numéricos a partir do software ABAQUS, versão 6.14, capazes de simular os comportamentos estrutural, térmico e termoestrutural de pequenas paredes de alvenaria estrutural constituídas de blocos de concreto. Para a modelagem numérica da pequena parede foram realizadas análises preliminares em prismas de três blocos com o intuito de simplificar e otimizar o processamento. Dentre as estratégias utilizadas foram considerados mecanismos de interação de contato entre os materiais para as análises estruturais e inserção de curvas de evolução de temperatura para as análises térmicas. O comportamento da pequena parede em temperatura ambiente sob carregamento de compressão, bem como, o gradiente de temperatura ao longo da seção transversal foi validado de acordo com os resultados experimentais existentes na literatura, sendo considerada a curva ISO 834-1:1999 para a situação de incêndio. Com estas validações, foi efetuado o modelo termoestrutural e analisado de forma qualitativa com os experimentos pertinentes. A tensão de ruptura e a distribuição de temperaturas do modelo numérico estiveram condizentes com os resultados experimentais, com desvios inferiores a 10%. Em contexto termoestrutural, observou-se que a redução das restrições quanto ao giro e o aumento da intensidade do carregamento reduziram a resistência ao fogo das pequenas paredes em relação ao critério de resistência mecânica, o qual, por sua vez, apresentou-se superior em comparação com o critério de isolamento térmico. / Structural masonry has been widely used Brazil as well as in the rest of the world. Among the advantages of this building system, it is worth to be highlighted the saving of time and materials and the reduction of the construction waste. For safety in the use of masonry, it is necessary to know its behavior when exposed to high temperatures due to the degradation of the properties of the materials, which are not contemplated by Brazilian standards. So designers usually apply foreign standards, which are based on materials properties and other parameters inherent of their respective countries. Regarding numerical modeling, this is an alternative of great efficiency and versatility due to the high costs involved in the experimental analyses and the need for adequate infrastructure for the tests. This work aimed to develop numerical models from the software ABAQUS 6.14 capable of simulating the structural, thermal and thermo-structural behavior of small walls of structural masonry of concrete blocks. For the numerical modeling of the small wall, preliminary analyses were carried out on three-block prisms in order to simplify and improve processing time. Among the strategies used were considered contact interaction between the materials for the structural analyses and insertion of temperature evolution curves for the thermal analyses. The behavior of the small wall at ambient temperature under load-bearing, as well as the temperature gradient along the cross section was validated according to the experimental tests available in literature, considering the ISO 834 standard fire curve. From these validations, the thermo-structural model was carried out and qualitatively analyzed with the available tests. The ultimate load and the distribution of the temperature of the numerical model were consistent with the experimental tests, with deviations less than 10%. In the thermo-structural context, it was observed that the reduction of the rotational restraints and the increase of the load reduced the fire resistance of the small walls in relation to the load-bearing criterion, which, in turn, was higher compared with the thermal insulation criterion.

There is an apparent lack of in-depth knowledge about the processes that may underlie the interaction between work and home life, and their relationships with employee health and well-being. Work and home has traditionally been considered as separate domains, but during the past decade of democracy, transformation developments (eg, Affirmative Action, Employment Equity) changed the nature of the labour market and economy. This facilitated the increase in the number of working single-parent, dual-earner families, and of women participating in the workforce, which in turned influenced the work-home interaction of employed individuals. Furthermore, various researchers regard burnout and engagement as important constructs to consider in the well-being of employees. The level of a person's wellbeing subsequently affects his/her functionality in both the work and home spheres. Thus, there is a need to identify ways which both the individual and the organisation can apply to increase personal well-being and the balance between work and home life. South Africa has 11 different national languages, and only 8,3% of the population actually speak English at home. Language differences should therefore be taken into account when administering questionnaires. Studies in South Africa generally report race, education, language, and understanding of English as the main factors which impact on construct and item comparability of psychometric tests. There is consequently an obvious need to translate research instruments before they are administered to individuals from different language groups. If language differences are not taken into account, invalid conclusions regarding the constructs under study could be made, with serious implications for culturally diverse settings such as in South Africa. The objectives of this research were to translate the Survey Work-Home Interaction Nijmegen (SWING), Maslach Burnout Inventory-General Survey (MBI-GS) and Utrecth Work Engagement Scale (UWES) into Afrikaans and Setswana, and to investigate the construct validity, construct equivalence and reliability of these instruments. Furthermore, differences between demographic groups regarding work-home interaction and well-being were investigated. Finally, a structural model was tested, which included job characteristics, negative and positive work-home interference (WHI) and well-being (burnout and engagement). A cross-sectional survey design was used. Random samples (N = 685) were taken from police stations in the North West province. Structural equation modelling (SEM) was used to determine the construct validity and equivalence of the measuring instruments and to test the structural model. The results indicated that work-home interaction can be described as a four-dimensional construct consisting of negative WHI, positive WHI, negative home-work interference (HWI), and positive HWI. This factor structure was equivalent across all three language groups and all the scales were reliable. A four-factor model was confirmed for burnout and included exhaustion, cognitive weariness, cynicism and professional efficacy. A one-factor model was found for engagement. Both translated instruments were found to be equivalent for the three language groups. Furthermore, a second order factor analysis revealed that the underlying structure of well-being consists of two negatively related and equivalent factors, namely burnout (exhaustion, cognitive weariness and cynicism) and an enlarged engagement construct (engagement and professional efficacy). Members reported more negative WHI than negative HWI, and more positive HWI than positive WHI. Statistically significant differences exist between demographic groups regarding work-home interaction based on language, gender, marital status. parental status and education. Statistically significant differences of wellness exist between demographic groups based on language and educational level. The results of the structural equation modelling revealed that job demands were directly and positively associated with negative WHI and burnout, while job resources were directly and positively associated with positive WHI and work engagement. This also indicates the partial mediating effect of WHI between job characteristics and wellness. In addition, a lack ofjob resources was associated with higher levels of burnout. Recommendations for future research were made. / Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.

Major changes that emphasise the importance of a balanced work and family life have occurred within organisations. Inability to manage this integration between the work and home domains can affect the performance of organisations and the wellbeing of their employees. In order to measure work-home interaction and wellbeing, it is important to use valid, equivalent and reliable instruments. However, there is a lack of empirical research when investigating work-home interaction, burnout and work engagement in the earthmoving equipment industry in South Africa. Furthermore, the earthmoving equipment industry is a multicultural environment and construct equivalence across subgroups therefore becomes important when measuring work-home interaction, burnout and work engagement across different cultural or language groups. It also seems relevant to consider differences in the work-home interaction and work wellness levels between important demographic groups in the earthmoving equipment industry. It appears as if burnout and engagement can be seen as part of the total wellness continuum; and that job characteristics may be related to burnout and engagement through negative and positive work-home interaction. However, little information was found that included these factors in a structural model for the earthmoving equipment industry. The objectives of this research were to test the psychometric properties of the Survey Work- Home Interaction - Nijmegen (SWING), the Maslach Burnout Inventory - General Survey (MBI-GS) and the Utrecht Work Engagement Scale (UWES); to determine if various demographic groups differ with regard to work-home interaction and wellbeing; and to test a structural model that includes job characteristics, work-home interaction and wellbeing for employees in the earthmoving industry. A cross-sectional survey design was used. Random samples (n = 528) were taken from employees in the earthmoving equipment industry in Gauteng, the Limpopo Province, Mpumalanga, the Northern Cape, the Western Cape, the Eastern Cape, Kwa-Zulu Natal and the North West Province. Structural equation modelling confirmed a four-factor model of work-home interaction which measures negative work-home interference, positive work-home interference, negative homework interference and positive home-work interference. This factor structure was equivalent across language, ethnicity, gender, education, marital status and parental status. All four factors were reliable. The participants reported more negative WHI than negative HWI, and more positive HWI than positive WHI. It was found that statistically significant differences that are based on age, gender, language, ethnicity, a partner's contribution to household income and the different business units exist between the demographic groups. The results confirmed a four-factor structure of burnout (exhaustion, cognitive weariness, cynicism and professional efficacy) and a two-factor structure of work engagement (including vigour and dedication). These structures were equivalent across language and education groups, and all scales were reliable. SEM analyses supported a two-factor structure for the wellness construct, consisting of burnout (exhaustion, cognitive weariness and cynicism) and engagement (vigour, dedication and professional efficacy), which was equivalent for the language and education groups. Statistically significant differences that are based on age, gender, language and the different business units were found between the demographic groups. Structural equation modelling showed that job demands are associated with negative WHI and consequently with burnout, providing support for a full-mediation effect of negative WHI. Job resources were associated with negative WHI and consequently with burnout, providing support for partial mediation of negative WHI between job resources and burnout. Job resources were also associated with positive WHI and consequently with engagement, providing support for partial mediation of positive WHI between job resources and engagement. Recommendations for the organisation and future research were made. / Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.

<p>Body image concerns and dieting emerge at an early age among girls and become more pronounced with increasing age. Knowledge about risk factors for disturbed eating is crucial in order to develop theoretical models and to suggest new paths for preventive efforts. The aim of the present thesis was to investigate the development of disturbed eating and to evaluate a conceptual model of predictors of body dissatisfaction and disturbed eating in girls. The included studies are part of a seven-year longitudinal project employing an accelerated multi-cohort design, including several age groups (7, 9, 11, 13, 15 years at inclusion). </p><p>Study I demonstrated a marked increase in the wish to be thinner and dieting attempts between the ages 10–14 and 9–13 years, respectively. In Study II, the Body Mass Index (BMI) predicted weight-related teasing and body dissatisfaction, and body dissatisfaction predicted restrained eating among Swedish girls in Grade 8 and Australian girls in Grades 7 and 8. Weight-related teasing partially mediated between BMI and body dissatisfaction in all three samples. Study III partially supported a conceptual model implying that BMI, weight-related teasing, and body dissatisfaction at 7–11 years predicted restrained eating among girls 12–14 years old. Study IV provided support for a conceptual model positing that BMI, body esteem, and to some extent weight-related teasing, predict body dissatisfaction and restrained eating during adolescence and young adulthood. </p><p>In conclusion, there was partial support for a conceptual model including these risk factors for disturbed eating among girls.</p>

Body image concerns and dieting emerge at an early age among girls and become more pronounced with increasing age. Knowledge about risk factors for disturbed eating is crucial in order to develop theoretical models and to suggest new paths for preventive efforts. The aim of the present thesis was to investigate the development of disturbed eating and to evaluate a conceptual model of predictors of body dissatisfaction and disturbed eating in girls. The included studies are part of a seven-year longitudinal project employing an accelerated multi-cohort design, including several age groups (7, 9, 11, 13, 15 years at inclusion). Study I demonstrated a marked increase in the wish to be thinner and dieting attempts between the ages 10–14 and 9–13 years, respectively. In Study II, the Body Mass Index (BMI) predicted weight-related teasing and body dissatisfaction, and body dissatisfaction predicted restrained eating among Swedish girls in Grade 8 and Australian girls in Grades 7 and 8. Weight-related teasing partially mediated between BMI and body dissatisfaction in all three samples. Study III partially supported a conceptual model implying that BMI, weight-related teasing, and body dissatisfaction at 7–11 years predicted restrained eating among girls 12–14 years old. Study IV provided support for a conceptual model positing that BMI, body esteem, and to some extent weight-related teasing, predict body dissatisfaction and restrained eating during adolescence and young adulthood. In conclusion, there was partial support for a conceptual model including these risk factors for disturbed eating among girls.

The scholastic geography of Lithuania has experienced the period of reforms during the past two decades. The imperative of the education shift has been determined by economical, social and cultural changes. The subject-matter of education and the training process have been corrected. It is a matter of great relevance to ascertain whether the subject-matter of geography education conforms to the requirements set by the documents of the Education System. The study contains the analysis of the conception of the education subject-matter and the structural parts of it. General structural model of geography science, as the basic source for the formation of the education subject-matter, is presented, the analysis of its elements is performed. The formation stages of geography science and the subject-matter of education are highlighted by emphasizing the basic periods of the education shift (scholastic geography to the education reform, contemporary scholastic geography). The content analysis of the schoolchildren achievements determined by the General Programmes and Education Standards is performed. The schoolchildren conception of geography is examined.

One of the very interesting demographic features in the US over the last three decades of the 20th century is the increase of the married women labor force participation rate. Over the same period, estimated labor supply elasticity varies substantially. This dissertation is to investigate the reasons behind them. I first study the determinants of the increase of the labor participation rate for married women with preschool-aged children over the last three decades of the 20th century. Using 5% samples of the Integrated Public Use Microdata Series (IPUMS) for 1980, 1990 and 2000, I find that the existing explanations proposed in the literature may only account for 9.6% increase in the 1980s and 70% decrease in the 1990s. In this paper, I find that the rising ratio of career type women can explain 30.33% of the growth in the labor force participation rate, and the change in the composition of career motivating career type women can at least explain 17.22% growth across cohorts. Women who have been working three years before their first childbearing are more likely to return to work after the childbearing period. The analyzing data is the National Longitudinal Survey of Young Women (NLSYW) from 1968 to 2003 and the National Longitudinal Survey of Youth 1979 (NLSY79) from 1979 to 2008. This dissertation sheds some insight about a puzzle on estimated married women's labor supply elasticity variation. This important puzzle (sometimes referred to as the Hausman puzzle) is that the estimated labor supply elasticity varies substantially even when similar frameworks and similar datasets are used. I study the role of budget sets in producing this wide range of estimates. In particular, I study the effect of the typical convexification approximation of the non-convex budgets, and the well-known Heckman critique of the lack of bunching at the kink points of budget sets in the Hausman model. I introduce measurement error in nonlabor income to create an uncertain budget constraint that no longer implies bunching at kink points. Using the Panel Study of Income Dynamics (PSID) of 1984 and 2001, I find that neither the convexification approximation nor using a model with random budget sets affects the estimates. These results demonstrate that variations in budget constraints alone do not explain the different estimates of labor supply elasticity. Changing the level of budget sets, for example by ignoring the state individual income tax, could affect the variation in elasticities.

There is an apparent lack of in-depth knowledge about the processes that may underlie the interaction between work and home life, and their relationships with employee health and well-being. Work and home has traditionally been considered as separate domains, but during the past decade of democracy, transformation developments (eg, Affirmative Action, Employment Equity) changed the nature of the labour market and economy. This facilitated the increase in the number of working single-parent, dual-earner families, and of women participating in the workforce, which in turned influenced the work-home interaction of employed individuals. Furthermore, various researchers regard burnout and engagement as important constructs to consider in the well-being of employees. The level of a person's wellbeing subsequently affects his/her functionality in both the work and home spheres. Thus, there is a need to identify ways which both the individual and the organisation can apply to increase personal well-being and the balance between work and home life. South Africa has 11 different national languages, and only 8,3% of the population actually speak English at home. Language differences should therefore be taken into account when administering questionnaires. Studies in South Africa generally report race, education, language, and understanding of English as the main factors which impact on construct and item comparability of psychometric tests. There is consequently an obvious need to translate research instruments before they are administered to individuals from different language groups. If language differences are not taken into account, invalid conclusions regarding the constructs under study could be made, with serious implications for culturally diverse settings such as in South Africa. The objectives of this research were to translate the Survey Work-Home Interaction Nijmegen (SWING), Maslach Burnout Inventory-General Survey (MBI-GS) and Utrecth Work Engagement Scale (UWES) into Afrikaans and Setswana, and to investigate the construct validity, construct equivalence and reliability of these instruments. Furthermore, differences between demographic groups regarding work-home interaction and well-being were investigated. Finally, a structural model was tested, which included job characteristics, negative and positive work-home interference (WHI) and well-being (burnout and engagement). A cross-sectional survey design was used. Random samples (N = 685) were taken from police stations in the North West province. Structural equation modelling (SEM) was used to determine the construct validity and equivalence of the measuring instruments and to test the structural model. The results indicated that work-home interaction can be described as a four-dimensional construct consisting of negative WHI, positive WHI, negative home-work interference (HWI), and positive HWI. This factor structure was equivalent across all three language groups and all the scales were reliable. A four-factor model was confirmed for burnout and included exhaustion, cognitive weariness, cynicism and professional efficacy. A one-factor model was found for engagement. Both translated instruments were found to be equivalent for the three language groups. Furthermore, a second order factor analysis revealed that the underlying structure of well-being consists of two negatively related and equivalent factors, namely burnout (exhaustion, cognitive weariness and cynicism) and an enlarged engagement construct (engagement and professional efficacy). Members reported more negative WHI than negative HWI, and more positive HWI than positive WHI. Statistically significant differences exist between demographic groups regarding work-home interaction based on language, gender, marital status. parental status and education. Statistically significant differences of wellness exist between demographic groups based on language and educational level. The results of the structural equation modelling revealed that job demands were directly and positively associated with negative WHI and burnout, while job resources were directly and positively associated with positive WHI and work engagement. This also indicates the partial mediating effect of WHI between job characteristics and wellness. In addition, a lack ofjob resources was associated with higher levels of burnout. Recommendations for future research were made. / Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.

Major changes that emphasise the importance of a balanced work and family life have occurred within organisations. Inability to manage this integration between the work and home domains can affect the performance of organisations and the wellbeing of their employees. In order to measure work-home interaction and wellbeing, it is important to use valid, equivalent and reliable instruments. However, there is a lack of empirical research when investigating work-home interaction, burnout and work engagement in the earthmoving equipment industry in South Africa. Furthermore, the earthmoving equipment industry is a multicultural environment and construct equivalence across subgroups therefore becomes important when measuring work-home interaction, burnout and work engagement across different cultural or language groups. It also seems relevant to consider differences in the work-home interaction and work wellness levels between important demographic groups in the earthmoving equipment industry. It appears as if burnout and engagement can be seen as part of the total wellness continuum; and that job characteristics may be related to burnout and engagement through negative and positive work-home interaction. However, little information was found that included these factors in a structural model for the earthmoving equipment industry. The objectives of this research were to test the psychometric properties of the Survey Work- Home Interaction - Nijmegen (SWING), the Maslach Burnout Inventory - General Survey (MBI-GS) and the Utrecht Work Engagement Scale (UWES); to determine if various demographic groups differ with regard to work-home interaction and wellbeing; and to test a structural model that includes job characteristics, work-home interaction and wellbeing for employees in the earthmoving industry. A cross-sectional survey design was used. Random samples (n = 528) were taken from employees in the earthmoving equipment industry in Gauteng, the Limpopo Province, Mpumalanga, the Northern Cape, the Western Cape, the Eastern Cape, Kwa-Zulu Natal and the North West Province. Structural equation modelling confirmed a four-factor model of work-home interaction which measures negative work-home interference, positive work-home interference, negative homework interference and positive home-work interference. This factor structure was equivalent across language, ethnicity, gender, education, marital status and parental status. All four factors were reliable. The participants reported more negative WHI than negative HWI, and more positive HWI than positive WHI. It was found that statistically significant differences that are based on age, gender, language, ethnicity, a partner's contribution to household income and the different business units exist between the demographic groups. The results confirmed a four-factor structure of burnout (exhaustion, cognitive weariness, cynicism and professional efficacy) and a two-factor structure of work engagement (including vigour and dedication). These structures were equivalent across language and education groups, and all scales were reliable. SEM analyses supported a two-factor structure for the wellness construct, consisting of burnout (exhaustion, cognitive weariness and cynicism) and engagement (vigour, dedication and professional efficacy), which was equivalent for the language and education groups. Statistically significant differences that are based on age, gender, language and the different business units were found between the demographic groups. Structural equation modelling showed that job demands are associated with negative WHI and consequently with burnout, providing support for a full-mediation effect of negative WHI. Job resources were associated with negative WHI and consequently with burnout, providing support for partial mediation of negative WHI between job resources and burnout. Job resources were also associated with positive WHI and consequently with engagement, providing support for partial mediation of positive WHI between job resources and engagement. Recommendations for the organisation and future research were made. / Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.