There are several methods of data classifications which can be utilized depends on the analysis. The figure above shows the housing cost in Vancouver with 4 different data classification. For example, If I am a journalist, I would choose natural breaks, because it shows audience the a very distinctive distribution of housing cost across metro Vancouver. If I am a real estate agent, I would use the manual break, which allow me to manually differentiate the housing cost near UBC. Each method can have biases, the manual break classification may skew the housing cost distribution which makes the map appear to have more affordable housing cost.
Data used for analysis in maps in the figure above are from 2011 census data. I think it is still reasonable to use the 2011 data, because the latest data is not available yet. However, if there are other sources available in later data, it might be useful to compare with the government published data and check if there is significant change.
Affordability measures the housing cost to income ratio to determine how affordable houses are in particular area. Housing affordability is a better indicator than housing cost alone, because it takes prospective home buyers’ income into account whether they can afford to own a house in certain area. For example, relatively high housing price can still be affordable to people with high income.
Housing affordability is classified into 4 rating categories: affordable, moderately affordable, seriously unaffordable, and severely unaffordable. These rating categories are determined by the 13th Annual Demographia International Housing Affordability Survey in 2017, which data was gathered from about 90 metropolitan centres. This data is recognized by the United Nation and World Bank, so it should be trust worthy. However, it may not fully represent the actual condition of specific area. Figure above compares the housing affordability between Vancouver, BC and London, ON.
Housing cost is one of the major factor that influence the livability of a city. Affordability can be a good indicator, because it suggest the income level and cost of living in a city. However, it should not be the only factor to consider in evaluating a city’s livability.