This thesis examines urban inequalities in the Canadian context and focuses on Ottawa, the capital city. Firstly, income inequality in the eight largest Census Metropolitan Areas in Canada, between 1971 and 2016, is examined through an analysis of income polarization and its spatial patterns. The middle-income group has declined across CMAs, while the low-income group has usually expanded. Concurrently, increasing spatial fragmentation is identified in every CMA examined. Local spatial autocorrelation identified clustering of high-income Census Tracts (CTs) suggesting that these areas are more resilient to fragmentation. Therefore, patterns of urban inequality are ones of an unequivocally disappearing middle-income population with an increasingly spatially fragmented urban income-scape. At local levels, inequality is manifest in processes such as gentrification. To increase the spatial and temporal ability to monitor and map gentrification in a large city, artificial intelligence and Google Street View imagery were used to identify visual improvements to properties that are indicative of gentrification between 2007 and 2016. A deep Siamese convolutional neural network (SCNN) and VGG19 backbone was trained to recognize visual gentrification-like changes of properties over time. This deep mapping model achieved a 95.6% level of accuracy in identifying the visual signs of property improvement using 86110 georeferenced photographs of individual properties in Ottawa, Canada. Given that the residential/commercial property itself is the atomic object of gentrification, properties identified as having undergone a gentrification like visual change were mapped as points to produce kernel density maps that reduce noise and identify regions of high visual property change intensity (hot spots). The intensity of visual property improvements exhibited strong concordance with the spatial pattern of building permits between 2011 and 2016. The results confirmed areas known to be undergoing gentrification and also presented areas where the process was not previously suspected of occurring. Thirdly, a select set of census-based quantitative methods of modelling gentrification were compared between 2006 and 2016 at both the CT and the finer dissemination area unit of analysis. All models were tested against their ability to predict the density of GSV-points per unit residential area that were predicted by the Siamese deep learning model. For the CT level, two new regression models were created using all the census variables identified within the learned literature. An OLS multivariable regression model was created using backward stepwise regression, after which only age (youth), dwelling-value, income & occupation were retained. Residual spatial dependence in the OLS required a spatial linear model specification. A spatially lagged simultaneous autoregressive model (SAR Lag_y) explained 57% of the variance in GSV-point density in Ottawa. Out of all the models tested, the SAR Lag_y possessed the strongest spatial correlation with the original pattern of GSV point density as measured using Lee's L bivariate spatial autocorrelation statistic. A second model was produced using quasibinomial regression in order to predict the probability of a given CT being gentrified. That model achieved 91.7% accuracy. Out of the five reproduced models from the literature, one preformed close to as well as our new models in predicting GSV-point density per unit residential area. While there is some agreement between models that purport to measure gentrification, there are considerable differences between models, which suggests that census-based gentrification measure should be locally focused.

This thesis presents evidence that income polarization is accompanied by increasing social-spatial disparities between areas of the city that were developed in different societal contexts, with different planning approaches, and that have different land use and transportation dynamics. An analysis of the social structure of the Toronto Metropolitan Area finds indications of widespread gentrification in the inner city, socioeconomic decline in the postwar suburbs, and sustained household affluence in the ever expanding outermost suburbs of the metropolitan area. It is argued that, as a political and social endeavor that is embedded in broader development regimes, urban planning influences social-spatial polarization to the extent that it influences urban form.

This thesis presents evidence that income polarization is accompanied by increasing social-spatial disparities between areas of the city that were developed in different societal contexts, with different planning approaches, and that have different land use and transportation dynamics. An analysis of the social structure of the Toronto Metropolitan Area finds indications of widespread gentrification in the inner city, socioeconomic decline in the postwar suburbs, and sustained household affluence in the ever expanding outermost suburbs of the metropolitan area. It is argued that, as a political and social endeavor that is embedded in broader development regimes, urban planning influences social-spatial polarization to the extent that it influences urban form.

O fenômeno de polarização de renda, conceitualmente diferente das medidas convencionais de desigualdade, surgiu inicialmente nos trabalhos de Foster e Wolfson (1992) e Esteban e Ray (1994). Há basicamente duas abordagens sobre polarização, mas de modo geral, ela pode ser definida como o aparecimento ou o desaparecimento de grupos na distribuição de renda de uma determinada população. Segundo Chakravarty (2010), a ocorrência de conflitos sociais está associada positivamente à polarização econômica, ou seja, quanto maior a polarização, mais elevada é a insatisfação social, culminando em índices mais elevados de violência e criminalidade. A polarização de renda também está associada ao crescimento econômico. Autores como Ezcurra (2009), Chakravarty (2010) e Brzezinski (2013) destacaram que o fenômeno da distribuição de renda que afeta o crescimento econômico não é a desigualdade, mas sim a polarização. Esta tese é composta por três ensaios acadêmicos. Os objetivos do primeiro ensaio foram mensurar e analisar a evolução e mudanças nos índices de polarização de renda propostos por Wolfson (1994) e Duclos, Esteban e Ray (2004) para o Brasil e suas regiões. Os resultados indicaram que houve redução nos índices de polarização de renda de Foster e Wolfson e de Duclos, Esteban e Ray para o País e suas cinco regiões entre 1995 e 2014. O objetivo do segundo ensaio foi testar se a polarização de renda, mensurada através de dois índices distintos, de Foster e Wolfson e de Duclos, Esteban e Ray, tem impacto sobre o crescimento econômico do Brasil e, caso houver, se o seu efeito é positivo ou negativo. Para tanto, foi utilizado o método de dados em painel para o período de 1995 a 2014, com dados das 27 unidades federativas brasileiras. Os resultados apontaram que o índice de bipolarização de Foster e Wolfson () possuiu uma relação negativa com o crescimento econômico para o conjunto de dados utilizados. Isso significa que uma classe média maior influencia de maneira positiva o crescimento econômico, já que quanto menos elevado é o índice , maior é o tamanho da classe média, e mais elevado é o crescimento econômico. Por outro lado, os índices de polarização de Duclos, Esteban e Ray () e de desigualdade de Gini não foram significativos. A finalidade do terceiro ensaio foi investigar a influência da polarização de renda sobre as taxas criminalidade no Brasil e comprovar se ela era realmente positiva. As proxies para criminalidade foram as taxas de homicídios intencionais e de roubos e furtos de veículos. Os resultados detectaram que o índice de polarização de Duclos Esteban e Ray (), assim como o de Gini, possuíram impactos positivos sobre as taxas de homicídios intencionais e de roubos e furtos de veículos, enquanto que a medida de polarização Foster e Wolfson () mostrou relação positiva significativa apenas para as taxas de homicídios intencionais. / The phenomenon of income polarization, conceptually different from conventional measures of inequality, first appeared in the studies of Foster and Wolfson (1992) and Esteban and Ray (1994). There are essentially two approaches to polarization, but in general it can be defined as the appearance or disappearance of groups in the income distribution of a given population. According to Chakravarty (2010), the occurrence of social conflicts is positively related to economic polarization, that is, the greater the polarization, the higher it is to social discontent, culminating in higher rates of violence and crime. Income polarization is also related to economic growth. Authors such as Ezcurra (2009), Chakravarty (2010) and Brzezinski (2013) have pointed out that the phenomenon of income distribution that affects economic growth is not inequality but polarization. This thesis consists of three academic essays. The purpose of the first essay were to measure and analyze the evolution and changes in the income polarization measure proposed by Wolfson (1994) and Duclos, Esteban and Ray (2004) for Brazil and its regions. The results showed that there was a reduction in Foster and Wolfson and Duclos, Esteban and Ray income polarization indices for the Country and its five regions between 1995 and 2014. The purpose of the second essay was to test whether the income polarization, measured by two different measures, by Foster and Wolfson and Duclos, Esteban and Ray had an impact on Brazilian economic growth, and if so, whether its effect is positive or negative. For that, the panel data method was used for the period 1995-2014, with data from the 27 Brazilian federative units. The results showed that Foster and Wolfson bipolarization index () had a negative relation with economic growth for the dataset used. This means that a larger middle class has positive influence on economic growth, since the lower the index, the larger the size of the middle class, and the higher the economic growth. On the other hand, Duclos, Esteban and Ray () and Gini measures were not significant. The purpose of the third essay was to investigate the influence of income polarization on crime rates in Brazil and to verify if it was indeed positive. Proxies for crime were the intentional homicide and theft and robbery of vehicles rates. The results showed that the Duclos Esteban and Ray polarization measure (), as well as Gini, had positive impacts on intentional homicide and theft and robbery of vehicles rates, while the Foster and Wolfson polarization measure () showed a positive and significant relationship only to intentional homicide rates.

O fenômeno de polarização de renda, conceitualmente diferente das medidas convencionais de desigualdade, surgiu inicialmente nos trabalhos de Foster e Wolfson (1992) e Esteban e Ray (1994). Há basicamente duas abordagens sobre polarização, mas de modo geral, ela pode ser definida como o aparecimento ou o desaparecimento de grupos na distribuição de renda de uma determinada população. Segundo Chakravarty (2010), a ocorrência de conflitos sociais está associada positivamente à polarização econômica, ou seja, quanto maior a polarização, mais elevada é a insatisfação social, culminando em índices mais elevados de violência e criminalidade. A polarização de renda também está associada ao crescimento econômico. Autores como Ezcurra (2009), Chakravarty (2010) e Brzezinski (2013) destacaram que o fenômeno da distribuição de renda que afeta o crescimento econômico não é a desigualdade, mas sim a polarização. Esta tese é composta por três ensaios acadêmicos. Os objetivos do primeiro ensaio foram mensurar e analisar a evolução e mudanças nos índices de polarização de renda propostos por Wolfson (1994) e Duclos, Esteban e Ray (2004) para o Brasil e suas regiões. Os resultados indicaram que houve redução nos índices de polarização de renda de Foster e Wolfson e de Duclos, Esteban e Ray para o País e suas cinco regiões entre 1995 e 2014. O objetivo do segundo ensaio foi testar se a polarização de renda, mensurada através de dois índices distintos, de Foster e Wolfson e de Duclos, Esteban e Ray, tem impacto sobre o crescimento econômico do Brasil e, caso houver, se o seu efeito é positivo ou negativo. Para tanto, foi utilizado o método de dados em painel para o período de 1995 a 2014, com dados das 27 unidades federativas brasileiras. Os resultados apontaram que o índice de bipolarização de Foster e Wolfson () possuiu uma relação negativa com o crescimento econômico para o conjunto de dados utilizados. Isso significa que uma classe média maior influencia de maneira positiva o crescimento econômico, já que quanto menos elevado é o índice , maior é o tamanho da classe média, e mais elevado é o crescimento econômico. Por outro lado, os índices de polarização de Duclos, Esteban e Ray () e de desigualdade de Gini não foram significativos. A finalidade do terceiro ensaio foi investigar a influência da polarização de renda sobre as taxas criminalidade no Brasil e comprovar se ela era realmente positiva. As proxies para criminalidade foram as taxas de homicídios intencionais e de roubos e furtos de veículos. Os resultados detectaram que o índice de polarização de Duclos Esteban e Ray (), assim como o de Gini, possuíram impactos positivos sobre as taxas de homicídios intencionais e de roubos e furtos de veículos, enquanto que a medida de polarização Foster e Wolfson () mostrou relação positiva significativa apenas para as taxas de homicídios intencionais. / The phenomenon of income polarization, conceptually different from conventional measures of inequality, first appeared in the studies of Foster and Wolfson (1992) and Esteban and Ray (1994). There are essentially two approaches to polarization, but in general it can be defined as the appearance or disappearance of groups in the income distribution of a given population. According to Chakravarty (2010), the occurrence of social conflicts is positively related to economic polarization, that is, the greater the polarization, the higher it is to social discontent, culminating in higher rates of violence and crime. Income polarization is also related to economic growth. Authors such as Ezcurra (2009), Chakravarty (2010) and Brzezinski (2013) have pointed out that the phenomenon of income distribution that affects economic growth is not inequality but polarization. This thesis consists of three academic essays. The purpose of the first essay were to measure and analyze the evolution and changes in the income polarization measure proposed by Wolfson (1994) and Duclos, Esteban and Ray (2004) for Brazil and its regions. The results showed that there was a reduction in Foster and Wolfson and Duclos, Esteban and Ray income polarization indices for the Country and its five regions between 1995 and 2014. The purpose of the second essay was to test whether the income polarization, measured by two different measures, by Foster and Wolfson and Duclos, Esteban and Ray had an impact on Brazilian economic growth, and if so, whether its effect is positive or negative. For that, the panel data method was used for the period 1995-2014, with data from the 27 Brazilian federative units. The results showed that Foster and Wolfson bipolarization index () had a negative relation with economic growth for the dataset used. This means that a larger middle class has positive influence on economic growth, since the lower the index, the larger the size of the middle class, and the higher the economic growth. On the other hand, Duclos, Esteban and Ray () and Gini measures were not significant. The purpose of the third essay was to investigate the influence of income polarization on crime rates in Brazil and to verify if it was indeed positive. Proxies for crime were the intentional homicide and theft and robbery of vehicles rates. The results showed that the Duclos Esteban and Ray polarization measure (), as well as Gini, had positive impacts on intentional homicide and theft and robbery of vehicles rates, while the Foster and Wolfson polarization measure () showed a positive and significant relationship only to intentional homicide rates.

O fenômeno de polarização de renda, conceitualmente diferente das medidas convencionais de desigualdade, surgiu inicialmente nos trabalhos de Foster e Wolfson (1992) e Esteban e Ray (1994). Há basicamente duas abordagens sobre polarização, mas de modo geral, ela pode ser definida como o aparecimento ou o desaparecimento de grupos na distribuição de renda de uma determinada população. Segundo Chakravarty (2010), a ocorrência de conflitos sociais está associada positivamente à polarização econômica, ou seja, quanto maior a polarização, mais elevada é a insatisfação social, culminando em índices mais elevados de violência e criminalidade. A polarização de renda também está associada ao crescimento econômico. Autores como Ezcurra (2009), Chakravarty (2010) e Brzezinski (2013) destacaram que o fenômeno da distribuição de renda que afeta o crescimento econômico não é a desigualdade, mas sim a polarização. Esta tese é composta por três ensaios acadêmicos. Os objetivos do primeiro ensaio foram mensurar e analisar a evolução e mudanças nos índices de polarização de renda propostos por Wolfson (1994) e Duclos, Esteban e Ray (2004) para o Brasil e suas regiões. Os resultados indicaram que houve redução nos índices de polarização de renda de Foster e Wolfson e de Duclos, Esteban e Ray para o País e suas cinco regiões entre 1995 e 2014. O objetivo do segundo ensaio foi testar se a polarização de renda, mensurada através de dois índices distintos, de Foster e Wolfson e de Duclos, Esteban e Ray, tem impacto sobre o crescimento econômico do Brasil e, caso houver, se o seu efeito é positivo ou negativo. Para tanto, foi utilizado o método de dados em painel para o período de 1995 a 2014, com dados das 27 unidades federativas brasileiras. Os resultados apontaram que o índice de bipolarização de Foster e Wolfson () possuiu uma relação negativa com o crescimento econômico para o conjunto de dados utilizados. Isso significa que uma classe média maior influencia de maneira positiva o crescimento econômico, já que quanto menos elevado é o índice , maior é o tamanho da classe média, e mais elevado é o crescimento econômico. Por outro lado, os índices de polarização de Duclos, Esteban e Ray () e de desigualdade de Gini não foram significativos. A finalidade do terceiro ensaio foi investigar a influência da polarização de renda sobre as taxas criminalidade no Brasil e comprovar se ela era realmente positiva. As proxies para criminalidade foram as taxas de homicídios intencionais e de roubos e furtos de veículos. Os resultados detectaram que o índice de polarização de Duclos Esteban e Ray (), assim como o de Gini, possuíram impactos positivos sobre as taxas de homicídios intencionais e de roubos e furtos de veículos, enquanto que a medida de polarização Foster e Wolfson () mostrou relação positiva significativa apenas para as taxas de homicídios intencionais. / The phenomenon of income polarization, conceptually different from conventional measures of inequality, first appeared in the studies of Foster and Wolfson (1992) and Esteban and Ray (1994). There are essentially two approaches to polarization, but in general it can be defined as the appearance or disappearance of groups in the income distribution of a given population. According to Chakravarty (2010), the occurrence of social conflicts is positively related to economic polarization, that is, the greater the polarization, the higher it is to social discontent, culminating in higher rates of violence and crime. Income polarization is also related to economic growth. Authors such as Ezcurra (2009), Chakravarty (2010) and Brzezinski (2013) have pointed out that the phenomenon of income distribution that affects economic growth is not inequality but polarization. This thesis consists of three academic essays. The purpose of the first essay were to measure and analyze the evolution and changes in the income polarization measure proposed by Wolfson (1994) and Duclos, Esteban and Ray (2004) for Brazil and its regions. The results showed that there was a reduction in Foster and Wolfson and Duclos, Esteban and Ray income polarization indices for the Country and its five regions between 1995 and 2014. The purpose of the second essay was to test whether the income polarization, measured by two different measures, by Foster and Wolfson and Duclos, Esteban and Ray had an impact on Brazilian economic growth, and if so, whether its effect is positive or negative. For that, the panel data method was used for the period 1995-2014, with data from the 27 Brazilian federative units. The results showed that Foster and Wolfson bipolarization index () had a negative relation with economic growth for the dataset used. This means that a larger middle class has positive influence on economic growth, since the lower the index, the larger the size of the middle class, and the higher the economic growth. On the other hand, Duclos, Esteban and Ray () and Gini measures were not significant. The purpose of the third essay was to investigate the influence of income polarization on crime rates in Brazil and to verify if it was indeed positive. Proxies for crime were the intentional homicide and theft and robbery of vehicles rates. The results showed that the Duclos Esteban and Ray polarization measure (), as well as Gini, had positive impacts on intentional homicide and theft and robbery of vehicles rates, while the Foster and Wolfson polarization measure () showed a positive and significant relationship only to intentional homicide rates.