# Brand Positioning by Correspondence Analysis

I was reading an article about visualization techniques using
*multidimensional scaling* (MDS), *the correspondence analysis* in
particular. The example used R, but as usual I want to find ways to do
it on Python, so here goes.

The correspondence analysis is useful when you have a two-way contingency table for which relative values of ratio-scaled data are of interest. For example, I here use a table where the rows are fashion brands (Chanel, Louis Vuitton, etc.) and the columns are the number of people who answered that the particular brand has the particular attribute expressed by the adjective (luxurious, youthful, energetic, etc.). (I borrowed the data from this article).

The correspondence analysis (or MDS in general) is a method of reducing dimensions to make the data more sensible for interpretation. In this case, I get a scatter plot of brands and adjectives in two-dimensional space, in which brands/adjectives more closely associated with each other are placed near each other.

As you see, brands like GAP, H&M, and Uniqlo are associated with youth, friendliness, and energy, while old-school brands like Chanel and Tiffany are associated with luxury and brilliance. This way of visualization is useful because the high-dimensional information (11 brands and 9 attributes) are reduced into two-dimensional plane, and the distance on that plane is meaningful.

Here’s the code and data: