Pattern-seeking, also called patternicity, is innate to mammals.
It is a survival instinct.
We can no more switch it off than our perception of colour.
Ignore the patterns at your own peril.
When you recklessly imperil the lives of those around you, they’re going to perceive two threats.
Original Threat + Traitor
Where there one concept, there is its opposite.
Where there is loyalty, there is disloyalty.
Where there is safety, there is danger.
Endangering others? Makes you responsible too.
Scorpion and the Frog. A snake doesn’t change its nature.
As for the mathematics, this is truly probabilistic. I haven’t seen this application before but it’s dead-right. This is why social science has proven (and hates to admit) that stereotypes are mostly true. Prejudice being acting according to these, where there is individual information to the contrary that they are ‘not like that.’ Self-preservation and precaution (Christian prudence) are the psychologically healthy reactions to logical assessments of risk.