Thank you. English isn't my first language, so for me feedback means a lot. Especially positive :)

My point was that representative heuristic made two errors: firstly, it violates "ratio rule" (= equates P(S|c) and P(c|S)), and secondly, sometimes it replaces P(c|S) with something else. That means that the popular idea "well, just treat it as P(c|S) instead of P(S|c); if you add P(c|~S) and P(S), then everything will be OK " doesn't always work.

The main point of our disagreement seem to be this:

(1) The degree to which c is representative of S is indicated by the conditional propability p (c | S)- that is, the propability of members of S have characterestic c.

1) Think about stereotypes. They are "represent" their classes well, yet it's extremely unlikely to actually meet the Platonic Ideal of Jew.

(also, sometimes there is some incentive for members of ethnic group to hide their lineage; if so, then P(stereotypical characteristics|member of group) is extremely low, yet the degree of resemblance is very high)

(this is somewhat reminds me of the section about Planning Fallacy in my earlier post).

2) I think that it can be argued that the degree of resemblance should involve P(c|~S) in some way. If it's very low, then c is very representative of S, even if P(c|S) isn't high.

Overall, inferential distances got me this time; I'm probably going to rewrite this post. If you have some ideas about how this text could be improved, I will be glad to hear them.