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npinskertoday at 12:29 AM1 replyview on HN

No, it's 50% -- given that e.g. the flip is H, the base probability is both 16% for HT and 16% for TH.


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maxbondtoday at 2:07 AM

To complete the circle, now that we have winnowed the space down to these options, we would normalize them and end up with 0.16 / (0.16 + 0.16) = 0.5 = 50% in both cases.

The reason I'm not putting % signs on there is that, until we normalize, those are measures and not probabilities. What that means is that an events which has a 16% chance of happening in the entire universe of possibility has a "area" or "volume" (the strictly correct term being measure) of 0.16. Once we zoom in to a smaller subset of events, it no longer has a probability of 16% but the measure remains unchanged.

In this previous comment I gave a longer explanation of the intuition behind measure theory and linked to some resources on YouTube.

https://news.ycombinator.com/item?id=35796740