Shin Huoy's GIS Portfolio

Choropleth maps are the most common type of quantitative thematic map, as data on many topics are commonly captured as area-level variables. I was tasked to create a choropleth map using data from Vancouver's 2011 Census survey. I decided to create a map of the population density of Vancouver, by dissemination areas. 

 

I learnt about the Modifiable Areal Unit problem, where the process of aggregating data at different spatial units can lead to biases in the representation of data. I also learnt about different data classification methods, including natural breaks (Jenk's algorithm), quantiles, equal intervals and manual breaks, as well as the pros and cons of each method and when to use each of them. 

 

In the creation of the choropleth map, I kept in mind that:

- choropleth maps often use standardized data, hence I showed population density instead of just population size of the differentially sized dissemination areas

- sequential color schemes are usually used to depict a trend that goes in a singular direction, whereas a diverging color scheme is used for bi-directional data (e.g. temperature that could be sub-zero), hence I used a sequential color scheme to depict increasing population density