Right, you’re saying it determines it in the one case where it fits, but it doesn’t in all the cases where it doesn’t fit. How about instead we just conclude that population isn’t really a factor?
I would say you’re right if it was GA and FL, which probably have very similar proportions of pool players, but the US has a far higher number of pool players than Europe (correct me if I’m wrong), which undermines the simple population explanation too.
Whoa.... Wait a minute... Population is not a "factor," "Factors" only com into play when results differ from what is expected. Population just related to those expectations.
High-school A, 2000 students
High-school B, 2000 students
High-school C, 2000 students
High-school D, 2000 students
High-school E, 2000 students
Let's say they all have a basketball team and the teams are roughly competitive with one another. OK, no big surprise.
Now suppose High-School A plays a game against an all-star from schools B, C, D, and E.
High-School A, 2000 students
High-Schools BCDE, 8000 students --better team and no surprise.
In the first case, we might try to explain what differences DO exist by looking at demographics, good coach, whether there is a youth basketball program, popularity of competing sports, and so forth. These are "factors."
But in the second case, we don't need such explanations of WHY the all-star team is better.