The connection seems to be "a link to this city's Wikipedia page appears in the named person's Wikipedia page". It does not look like the contents of the city's page have any bearing, only the person's page.
That can't be right, or at leats not the whole story. For example, "Joaquin Pheonix" is the most searched person from Gainesville. But there's no mention of Gainesville, or even the state of Florida, on his Wikipedia page. But it does appear to be true that he was a "resident" (more or less) during his teenage years [0].
They explicitly say that in their "data and methods" blurb:
> Person/city associations were based on the thousands of “People from X city” pages on Wikipedia. The top person from each city was determined by using median pageviews (with a minimum of 1 year of traffic). We chose to include multiple occurrences for a single person because there is both no way to determine which is more accurate and people can “be from” multiple places.
That’s made obvious by Steve Jobs having an oversized presence on the map in Portland, Oregon... having only gone to college there briefly, before dropping out, and having no other connection to the city. He was more like a visitor than a resident.
Yes, this is what I've seen too. Basically if the person's individual wikipedia page has a category at the bottom like "People from X city", then they will be included in the rankings for the city. So it leaves out a bunch of people who were missing that tag.
It would be cool if they could also include the "Notable People" for each city in this ranking in the future.
[0] https://www.gainesville.com/article/LK/20040526/News/6041599...
EDIT: However, he is on Wikipedia's "List of People from Gainesville, FL" [1], so I bet those lists were the primary source of information.
[1] https://en.wikipedia.org/wiki/List_of_people_from_Gainesvill...