Negative Correlation between Looks and Talent

Here is a good point about correlations:

The paper claims "Across the highest adult performance levels, peak performance is negatively correlated with early performance." This is a classic example of Berkson's paradox.

Here is a simplified example to understand this: Assume that to be a successful actor you have to be either extremely good looking or extremely talented. Assume also that talent and looks are independent in the population. However, among sucessful actors you will observe a negative correlation between looks and talent. This doesn't meant anything beyond the selection process and should not be extrapolated.

My favorite example-joke of this is that basketball points scored is negatively associated with height among NBA players. (because to be an NBA player you have to be very tall OR be very good at scoring).

It refers to this AAAS Science paper, mirrored here. More discussion here.

The paper concerns comparing elite adult performance to elite youth performance. The top performing adults come from the top performing youths. But if you look at the correlation the wrong way, as in this paper, you might wrongly conclude the opposite.