This is a special post for quick takes by Adele Lopez. Only they can create top-level comments. Comments here also appear on the Quick Takes page and All Posts page.
Sometimes the point is specifically to not update on the additional information, because you don't trust yourself to update on it correctly.
Classic example: "Projects like this usually take 6 months, but looking at the plan I don't see why it couldn't be done in 2... wait, no, I should stick to the reference class forecast."
Sure, but I think people often don't do that in the best way (which is determined by what the mathematically correct way is).
Why does it make sense to use reference class forecasting in that case? Because you know you can't trust your intuitive prior, and so you need a different starting point. But you can and should still update on the evidence you do have. If you don't trust yourself to update correctly, that's a much more serious problem -- but make sure you've actually tried updating correctly first (which REQUIRES comparing how likely the evidence you... (read more)