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Comment by cscheid | Hacker News Reader

Seriously, though, there's one nomogram you (yes you) should know about and have it well-enough engraved in your mind's eye that you can use it with eyes closed. A nomogram for Bayes' theorem: https://www.ovid.com/journals/nejm/abstract/10.1056/nejm1975...

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That was a bit small on my screen. Found an interactive one here that's scalable - https://www.medcalc.org/en/calc/fagans-nomogram.php

That is cool, although it took me awhile to understand it because the posterior probability is on the left and the prior probability is on the right, and because it uses D=Disease and T=Test when I am used to seeing D=Data.

Neat. This is based on Bayes' rule in its odds form[1], or more specifically in log-odds form, where evidence is additive[2].

[1]: https://entropicthoughts.com/bayes-rule-odds-form

[2]: https://entropicthoughts.com/sensitivity-counts-against-you

Actually I find nomograms in log form really cool for making naive bayes classifiers 'explainable'. One can even add density for continuous values.

IMHO this is so much nicer than e.g. decisions tree visualizations (which everyone quotes for the most explainable AI models).

It is indeed a great tool for visualizing Bayesian relations. You can even "feel" the sensitivity.

Can you use actually use it eyes closed? Never heard of that level of precision in the mind's eye

You're right that I can't reproduce it like a phone camera could, and that the more precise you are the better (and it might be that with my eyes closed I'm doing something closer to addition in log-odds, like a separate comment responded), but this is super useful even coarsely. The visual affordance gives Bayes's theorem a physicality unlike any other tool I've found.

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