then I would expect cities to stand out more (relative to altitude) on the obesity maps like they do on the maps you linked.
But I don’t see that (there is a noticeable correlation, but it looks smaller than the altitude one to me), so I think it’s more likely the causality is better approximated with a graph which has an arrow from altitude to obesity than not.
If the causality was:
obesity ← socioeconomic status → altitude
then I would expect cities to stand out more (relative to altitude) on the obesity maps like they do on the maps you linked.
But I don’t see that (there is a noticeable correlation, but it looks smaller than the altitude one to me), so I think it’s more likely the causality is better approximated with a graph which has an arrow from altitude to obesity than not.