[pt] Esta tese é composta por três artigos empíricos que utilizam dados de venda de uma cadeia de lojas de produtos eletroeletrônicos e de características de seus clientes. O primeiro investiga o efeito de características, como gênero, idade, escolaridade e renda, na probabilidade do cliente de receber desconto. Ele tem o objetivo de averiguar se a autoridade de decisão de preço final dada aos vendedores está sendo bem usada. Quando há discriminação de preços, clientes com renda mais alta devem ter menor probabilidade de receber descontos. Por outro lado, descontos podem ser dados por outros motivos, diferentes daquele desejado pela firma. Uma vez que o cliente percebe que o vendedor tem poder de decisão sobre o preço final, ele pode desejar começar um processo de barganha para reduzir o preço que pagará. O resultado deste processo pode também depender das características do cliente, se estas afetarem a habilidade de barganhar. Neste caso, quanto maior a habilidade do cliente de barganhar pelo desconto, maior este será. Como encontramos que a probabilidade de receber descontos aumenta com a renda e escolaridade do cliente, e o valor do desconto também é maior para pessoas com mais alta renda e mais educadas, concluímos que o desconto não está sendo dado como resultado de discriminação de preços, mas como o resultado de uma barganha. O segundo artigo estima o efeito de informação assimétrica sobre o financiamento da compra de produtos, usando o plano de pagamento escolhido e as características não observadas do cliente. Decompomos o efeito em seleção adversa e um componente causal, usando técnica similar à usada por Adams, Eivan and Levin (2009). Encontramos um efeito marginal significante e concluímos que o efeito causal da escolha do plano de pagamento é maior que aquele causado pela seleção adversa. Um aspecto chave da estratégia de identificação é a escolha da variável exógena. Usamos uma variável binária que é um quando a compra é feita num mês de saldão, meses estes quando há um plano especial: onze parcelas sem juros. A variável usada claramente influencia a escolha do plano de pagamento, mas o repagamento não depende diretamente dela, uma vez que nosso instrumento não está associado ao valor do colateral do empréstimo. O terceiro artigo estuda o repasse para os preços da primeira redução de IPI de 2009. A redução ocorreu para quatro diferentes produtos: refrigeradores, fogões, máquinas de lavar e tanquinhos. Observamos o efeito do IPI nos preços e nas características dos clientes. Encontramos que a ocorrência da redução do IPI gera uma redução de 5,97 porcento no preço, quando usamos um modelo linear simples e uma redução de 2,98 porcento no preço, quando usamos um efeito fixo de produto. Gênero, idade, renda e escolaridade dos clientes que compram eletrodomésticos não mudam significativamente com a redução do IPI. / [en] This dissertation is composed of three independent empirical articles that use data on home and kitchen appliances and image equipment sales of one specific chain store and their clients characteristics. The first one investigates the effect of the client s characteristics, such as gender, age, education and income, on the probability of receiving a discount. It intends to investigate if the pricing authority that is delegated to the salespeople is being well used. If the effect of delegation were to implement price discrimination, clients with higher income would have a lower probability of getting a discount. On the other hand, discounts can be given for a different reason than the one desired by the firm. Once the customer recognizes that the salesperson has some discretion over the prices, she may wish to engage in bargaining to decrease the final price. The outcome of this process may also depend on the customer s characteristics if they affect the customer s skill in bargaining. In this case, the greater the client s ability, the bigger the discount. Since we find that the probability of receiving a discount is increasing in the client s income and education, and the value of the discount is also bigger for people with higher income and better education, we conclude that the discount giving is not a result of price discrimination, but a result of a bargaining process. The second article estimates the effect of asymmetric information on consumer loans, using the payment plan chosen by the client and his observable characteristics. We decompose the effect into an adverse selection and a causal component using a technique similar to Adams, Einav and Levin (2009). We find significant marginal effects for both components and that the causal effect of the payment plan choice is greater than the one caused by the adverse selection. A key aspect of the identification strategy is the choice of the exogenous variable. We use a dummy variable that is one when the month of the purchase is one of the saldão months, that is, when one special payment plan is also available: eleven monthly payments, with zero interest rate. The variable used clearly influences the payment plan choice but the repayment behavior does not depend directly on it, since it is not directly related to the value of the debt collateral. The third article studies the retail market effects of the first tax stimulus episode of 2009, when the government reduced the IPI (Industrialized Products Tax) of certain categories of kitchen and home appliances. Tax rates vary depending on the product. The reduction occurred to four different products: refrigerators, stoves, washing machines and non automatic washing machines. We estimate the effect of the IPI reduction on prices and the composition of demand. We find that the IPI reduction lead to a 5.97 percent reduction on price, when we use a simple linear model and a 2.98 percent reduction, when we control for product fixed effects. The characteristics of consumers who acquire the appliances do not change significantly with the reduction.

The primary aim of the study was to design a model for changing teachers' attitudes towards the value of teaching critical thinking skills. Currently, information regarding the conceptualisation of this topic is inadequate and vague. In this study the nature of the complexities involved in the management and implementation of the teaching of critical thinking skills were researched through a literature study and an empirical investigation. A model was then designed for the effective management of the implementation thereof. The findings from the research indicated that teachers' attitudes towards the value of teaching critical thinking skills to learners are negative. It also became evident that the school principal should manage the implementation of the teaching of critical thinking skills to learners. The focus of the proposed model is on how teachers' attitudes towards the value of teaching critical thinking skills can be changed to ensure quality educative teaching and learning in and outside of the classroom. The study therefore serves to present a useable model for the management of the implementation of teaching critical thinking skills to learners. The study is further based on a well balanced opinion as experiences of teachers in the senior phase (grades 7, 8, & 9) were investigated by means of structured questionnaires. Recommendations regarding research findings were made for stakeholders and education departmental officials to note. / Thesis (Ph.D. (Education Management))--North-West University, Vaal Triangle Campus, 2010.

The primary aim of the study was to design a model for changing teachers' attitudes towards the value of teaching critical thinking skills. Currently, information regarding the conceptualisation of this topic is inadequate and vague. In this study the nature of the complexities involved in the management and implementation of the teaching of critical thinking skills were researched through a literature study and an empirical investigation. A model was then designed for the effective management of the implementation thereof. The findings from the research indicated that teachers' attitudes towards the value of teaching critical thinking skills to learners are negative. It also became evident that the school principal should manage the implementation of the teaching of critical thinking skills to learners. The focus of the proposed model is on how teachers' attitudes towards the value of teaching critical thinking skills can be changed to ensure quality educative teaching and learning in and outside of the classroom. The study therefore serves to present a useable model for the management of the implementation of teaching critical thinking skills to learners. The study is further based on a well balanced opinion as experiences of teachers in the senior phase (grades 7, 8, & 9) were investigated by means of structured questionnaires. Recommendations regarding research findings were made for stakeholders and education departmental officials to note. / Thesis (Ph.D. (Education Management))--North-West University, Vaal Triangle Campus, 2010.