"The professor notes that breed accounts for just 9% of variation in behavior in individual dogs while, for certain behavioral traits, age is a better predictor

"The professor notes that breed accounts for just 9% of variation in behavior in individual dogs while, for certain behavioral traits, age is a better predictor." "9% of variation" contradicts "unrelated" in the headline. And if 9% of the time one breed is being friendly while the other is being agressive, that's a large practical difference. That 9% can easily be considered to support rather than refute stereotype accuracy.