Chad Clark's Open Journal : 2009-03-15

1) Is 7-11 placement related to household income in the Calgary region?

A first look shows there may be a correlation but a number of other factors
were not examined.

The write up reads:

"""

There doesn't appear to be any mathematical link between the distances of
the 7-11 stores to all other 7-11 stores (so they're not clustered or
thinly spread out).

...

From the image of the city with income levels and store locations it
appears to me that the stores are more densely located in regions average
and below average income levels. This may be coincidence. I imagine it
could be the case that store placement is more dependent on factors like
population density, residential vs industrial land use, and age of the
neighbourhood.

"""