-I replied that "obviously a man" is unsophisticated. I had been thinking of gendering in terms of [naïve Bayes models](https://www.lesswrong.com/posts/gDWvLicHhcMfGmwaK/conditional-independence-and-naive-bayes): you observe some features, use those to assign (probabilities of) category membership, and then use category membership to make predictions about whatever other features you might care about but can't immediately observe. Sure, it's possible for an attempted clocking to be mistaken, and you can have third-gender categories such that AGP trans women aren't "men", but they're still not drawn from anything close to the same distribution as cis women.
+I replied that "obviously a man" was an unsophisticated form of trans-skepticism. I had been thinking of gendering in terms of [naïve Bayes models](https://www.lesswrong.com/posts/gDWvLicHhcMfGmwaK/conditional-independence-and-naive-bayes): you observe some features, use those to assign (probabilities of) category membership, and then use category membership to make predictions about whatever other features you might care about but can't immediately observe. Sure, it's possible for an attempted clocking to be mistaken, and you can have third-gender categories such that AGP trans women aren't "men"—but they're still not drawn from anything close to the same distribution as cis women.
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+Sophia replied with an information-theoretic analysis of passing (which I would [later adapt into a guest post for this blog](/2018/Oct/the-information-theory-of-passing/)). If the base rate of AGP transsexualism in Portland was 0.1%, someone would need log<sub>2</sub>(99.9%/0.1%) ≈ 9.96 ≈ 10 bits of evidence to clock her as trans. If one's facial structure was of a kind four times more likely to be from a male than a female, that would only contribute 2 bits. Sophia was 5′7″, which is about where the female and male height distributions cross over, so she wasn't leaking any bits there. And so on—the prospect of passing in naturalistic settings is a different question from whether there exists evidence that a trans person is trans. There _is_ evidence—but as long as it's comfortably under 10 bits, it won't be a problem.
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+I agreed that for most people in most everyday situations it probably didn't matter. _I_ cared because I was a computational philosophy of gender nerd, I said, [linking to a program I had written](https://github.com/zackmdavis/Persongen/blob/8fc03d3173/src/main.rs) to simulate sex classification based on personality, using data from [a paper by Weisberg _et al._ about sex differences in correlated "facets" underlying the Big Five personality traits](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149680/). (For example, studies had shown that women and men didn't differ in Big Five Extraversion, but if you split "Extraversion" into "Enthusiasm" and "Assertiveness", there were small sex differences pointing in opposite directions, with men being more assertive.) My program generated random examples of women's and men's personality stats according the Weisberg _et al._ data, and then tried to classify the "actual" sex of each example given only the personality stats—only reaching 63% accuracy, which was good news for androgyny fans like me.