Interesting visualizations that confirm what personal observations definitely suggest, but....no citation as to where the data came from? Seems pretty important

Interesting visualizations that confirm what personal observations definitely suggest, but....no citation as to where the data came from? Seems pretty important to me. I find it hard to believe that there are so few "shops" north of 96th Street, which is what that map that says "all 10,298 NYC shops" suggests.