Comment by c1ccccc1 | Hacker News Reader

Comment by c1ccccc1 | Hacker News Reader

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Would you also get triggered if you saw people make a bet at, say, $24 : $87 odds? Would you shout: "No! That's too precise, you should bet $20 : $90!"? For that matter, should all prices in the stock market be multiples of $1, (since, after all, fluctuations of greater than $1 are very common)?

If the variance (uncertainty) in a number is large, correct thing to do is to just also report the variance, not to round the mean to a whole number.

Also, in log odds, the difference between 5% and 10% is about the same as the difference between 40% and 60%. So using an intermediate value like 8% is less crazy than you'd think.

People writing comments in their own little forum where they happen not to use sig-figs to communicate uncertainty is probably not a sinister attempt to convince "everyone" that their predictions are somehow scientific. For one thing, I doubt most people are dumb enough to be convinced by that, even if it were the goal. For another, the expected audience for these comments was not "everyone", it was specifically people who are likely to interpret those probabilities in a Bayesian way (i.e. as subjective probabilities).

> Would you also get triggered if you saw people make a bet at, say, $24 : $87 odds? Would you shout: "No! That's too precise, you should bet $20 : $90!"? For that matter, should all prices in the stock market be multiples of $1, (since, after all, fluctuations of greater than $1 are very common)?

No.

I responded to the same point here: https://news.ycombinator.com/item?id=44618142

> correct thing to do is to just also report the variance

And do we also pull this one out of thin air?

Using precise number to convey extremely unprecise and ungrounded opinions is imho wrong and to me unsettling. I'm pulling this purely out of my ass, and maybe I am making too much out of it, but I feel this is in part what is causing the many cases of very weird, and borderline associal/dangerous behaviours of some associated with the rationalists movement. When you try to precisely quantify what cannot be, and start trusting those numbers too much, you can easily be led to trust your conclusions way too much. I am 56% confident this is a real effect.

I mean, sure people can use this to fool themselves. I think usually the cause of someone fooling themselves is "the will to be fooled", and not so much that fact that they used precise numbers in the their internal monologue as opposed to verbal buckets like "pretty likely", "very unlikely". But if you estimate 56% it sometimes actually makes a difference, then who am I to argue? Sounds super accurate to me. :)

In all seriousness, I do agree it's a bit harmful for people to use this kind of reasoning, but only practice it on things like AGI that will not be resolved for years and years (and maybe we'll all be dead when it does get resolved). Like ideally you'd be doing hand-wavy reasoning with precise probabilities about whether you should bring an umbrella on a trip, or applying for that job, etc. Then you get to practice with actual feedback and learn how not to make dumb mistakes while reasoning in that style.

> And do we also pull this one out of thin air?

That's what we do when training ML models sometimes. We'll have the model make a Gaussian distribution by supplying both a mean and a variance. (Pulled out of thin air, so to speak.) It has to give its best guess of the mean, and if the variance it reports is too small, it gets penalized accordingly. Having the model somehow supply an entire probability distribution is even more flexible (and even less communicable by mere rounding). Of course, as mentioned by commenter danlitt, this isn't relevant to binary outcomes anyways, since the whole distribution is described by a single number.

> and not so much that fact that they used precise numbers in the their internal monologue as opposed to verbal buckets like "pretty likely", "very unlikely"

I am obviously only talking from my personal anecdotal experience, but having been on a bunch of coffee chat in the last few months with people in the AI safety field in SF, and a lot of them being Lesswrong-ers, I experienced a lot of those discussions with random % being thrown in succession to estimate the final probability of some event, and even though I have worked in ML for 10+ years (so I would guess more constantly aware of what a bayesian probability is than the average person), I do find myself often swayed by whatever numbers comes out at the end and having to consciously take a step back and pull myself from instinctively trusting this random number more than I should. I would not need to pull myself back, I think, if we were using words instead of precise numbers.

It could be just a personal mental weakness with numbers with me that is not general, but looking at my interlocutors emotional reactions to their own numerical predictions I do feel quite strongly that this is a general human trait.

> It could be just a personal mental weakness with numbers with me that is not general, but looking at my interlocutors emotional reactions to their own numerical predictions I do feel quite strongly that this is a general human trait.

Your feeling is correct; anchoring is a thing, and good LessWrongers (I hope to be in that category) know this and keep track of where their prior and not just posterior probabilities come from: https://en.wikipedia.org/wiki/Anchoring_effect

Probably don't in practice, but should. That "should" is what puts the "less" into "less wrong".

Ah thanks for the link, yes this is precisely the bias I am feeling falling victim to if not making an effort to counter it.

> If the variance (uncertainty) in a number is large, correct thing to do is to just also report the variance

I really wonder what you mean by this. If I put my finger in the air and estimate the emergence of AGI as 13%, how do I get at the variance of that estimate? At face value, it is a number, not a random variable, and does not have a variance. If you instead view it as a "random sample" from the population of possible estimates I might have made, it does not seem well defined at all.

I meant in a general sense that it's better when reporting measurements/estimates of real numbers to report the uncertainty of the estimate alongside the estimate, instead of using some kind of janky rounding procedure to try and communicate that information.

You're absolutely right that if you have a binary random variable like "IMO gold by 2026", then the only thing you can report about its distribution is the probability of each outcome. This only makes it even more unreasonable to try and communicate some kind of "uncertainty" with sig-figs, as the person I was replying to suggested doing!

(To be fair, in many cases you could introduce a latent variable that takes on continuous values and is closely linked to the outcome of the binary variable. Eg: "Chance of solving a random IMO problem for the very best model in 2025". Then that distribution would have both a mean and a variance (and skew, etc), and it could map to a "distribution over probabilities".)

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