No, I saw that page and it doesn't say anything meaningful about how they arrived at this. It says _that_ they expanded the model, and various notes about resolution, they use to communicate the labeling they arrived at -- but nothing meaningful about the input data used, any statistical methodology, etc.

> my Motivf colleagues and I refined the ad hoc models and produced what you might call the “official” American Nations Model spreadsheets for the United States, mapping the regional cultures at county-level resolution.

> This summer, we’ve expanded the analytical model to the rest of North America covered in American Nations.