&gt; Is it sexism to make assumptions that are probabilistically correct?<p>Judging people based on group membership rather than individually on axis that are not essentially tied (even if they are correlated with) that group membership is prejudice; prejudiced based on sex is sexism. So, yes, making probabilistic assumptions based on sex and acting on them is, in many cases, sexism.<p>&gt; ) For a woman I don&#x27;t know, I buy her frozen yogurt. 2) For a man I don&#x27;t know, I buy him pizza.<p>If you want to get people food that they want, you can just ask them. (And, in any case, context is probably more important than sex: IME, women are more likely to prefer pizza to froyo for a meal, and men are more likely to prefer froyo to pizza for a dessert; there&#x27;re are very few contexts where &quot;pizza&quot; and &quot;froyo&quot; are comparable alternatives where sex would be the prime differentiator on how people would respond to them -- and elevating sex above more relevant decision criteria is a pretty strong indication of sexism.)