Tyrrell_McAllister comments on What Bayesianism taught me - Less Wrong
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Well ... you can have an expected direction, just not if you account for magnitudes.
For example if I'm estimating the bias on a weighted die, and so far I've seen 2/10 rolls give 6's, if I roll again I expect most of the time to get a non-6 and revise down my estimate of the probability of a 6; however on the occasions when I do roll a 6 I will revise up my estimate by a larger amount.
Sometimes it's useful to have this distinction.
Yes, on reflection it was a poor choice of words. I was using "expect" in that sense according to which one expects a parameter to equal zero if the expected value of that parameter is zero. However, while "expected value" has a well-established technical meaning, "expect" alone may not. It is certainly reasonably natural to read what I wrote as meaning "my opinion is equally likely to be swayed in either direction," which, as you point out, is incorrect. I've added a footnote to clarify my meaning.