> feels like an over-estimate That's why I said at least 3 bits. If chess players are rarer, then knowing someone is a chess player is a stronger filter. (By t

> feels like an over-estimate That's why I said at least 3 bits. If chess players are rarer, then knowing someone is a chess player is a stronger filter. (By the same token, knowing that they're not is a weaker one; but that's not the case we're discussing.)