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by yummyfajitas 4025 days ago
A prior (e.g., P(recruiter|woman at tech event) = g ) is accurate if the actual portion of women at tech events who are recruiters is g.

Secondly, suppose the prior is accurate. Lets take a very simple model, suppose g_woman = 0.25 and g_man = 0.05. Further, suppose networking with a developer has a value of 1 utilon and networking with a recruiter has 0 utilons of value.

If I network in order to maximize utility, based solely on my prior (i.e. ignoring any posterior info), I've added 95 utilons to the world for every 100 people I network with. If I behave irrationally and network with men and women equally, I've added only 85 utilons to the world. I've harmed 47.5 men in order to benefit 37.5 women - on net I've harmed 10 people.

(If posterior information is available, then you can even increase utility beyond 95/100.)

This is why math matters, and why carefully thinking things through rather than spouting incorrect soundbites (as the author does) is important.

2 comments

How do you go from a simple abstract model that is rhetorically convenient to actually guiding concrete behavior?

If you walk into a conference and use that model you aren't using anything very meaningful to guide your behavior, you're using a model that probably isn't very true (I would presume that the modal value of networking is ~0, with the occasional valuable introduction bringing the mean up above that).

Going from models to reality is basically a process of expanding the model until it accounts for enough that you are confident it will work.

Also, the particular model I use only requires a mean positive utility - even if we take a model like yours, the conclusion is unchanged. Variance simply goes up, but the best option is still not talking to women.

How do you measure if it works or not?

I mean, if you only talk to men and then measure where you derived utility, I'm not sure you've properly evaluated the model yet (if you interact with a certain percentage of women at conferences and keep track of all this in order to make sure that your model is working out properly, well then, more power to you).

I really can't write an entire textbook on Bayesian decision theory in an HN comment. Honestly, if I could, I'd write the actual textbook - we really need a good one. I'm not claiming to have a rigorously tested model of exactly who to network with at a conference. I'm claiming that ignoring base rates results in worse decisions.

And if I made this point in a non-political context - e.g., "you must account for the base rate for $disease when interpreting a $disease test" - no one would be disputing it.

If you or anyone else here can even present a (utilitarian) model where ignoring base rates leads to a better decision, by all means do it. I'd love to see this, though I suspect the actual outcome of such an effort will merely be the person attempting to do it gaining a much better understanding of Bayes rule.

My issue isn't with the point that the base rate matters, it's with the mathematricality.

And I do think that is fair, if there is not a simple way of actually measuring the utility and such (re your complaint about $diseases, medicine has at least somewhat reliable tests), all the stuff about the modeling is just theatrics.

Am I correct in interpreting this post as saying "I agree base rate matters, I just wish you didn't provide a toy example illustrating that?"

Also, I now strongly recommend you go through the exercise I suggested. Then you'll realize that accurate tests do NOT somehow eliminate the need for models or accounting for base rates.

First, morality matters. And you've forcibly ejected morality from your equation.

Second, network effects matter. You're not just creating utilons for yourself, you're creating a system that creates utilons. Even within the small and inaccurate world of your invented model, you're not following through to conclusions.

Third, you're making some very arbitrary assumptions, and ignoring other reasonable assumptions. For starters, do you give everyone you network with equal time? If you encounter a recruiter, do you give them the same amount of effort you would give to an engineer, or do you extract yourself and move on to the next person? The expense of equal input is not nearly as high as you're presenting here, assuming you don't "behave irrationally" and give everyone equal time whether it's effective or not.

Pretending that bias and excuses are intellectual rigor by inserting arbitrary, invented numbers into an imaginary equation is just an appeal to authority fallacy.

Blfr is right, I'm taking utilitarianism as my morality. Specifically, I believe networking with a developer (regardless of gender) is moral, and networking with a recruiter is useless. What morality do you take?

Secondly, I didn't make any assumption that the utility is all mine. The 1 utilon can be split between both parties in some arbitrary manner, it doesn't change the result.

Third, you are correct that I my constraint may not be #recruiters + #developers = 100. It might be alpha x #recruiters + #developers = 100 for alpha < 1. That doesn't change the optimal course of action - my best bet is always to minimize time I spend with recruiters.

Now if you think my model doesn't work, present a better one. But if you are making a fundamentally moral and non-utilitarian point ("networking with lady developers is intrinsically good no matter how many puppies get killed!!!!!"), make that point and don't waste time on positive claims if the truth of the positive claims is irrelevant anyway.

Also, you seem to wildly misunderstand what an appeal to authority is. An appeal to authority would be "I asked Eliezer Yudkowsky and he said I was right." Writing down a simple mathematical model is not remotely an appeal to authority, that's just careful reasoning.

Applying a pretense of mathematical rigor is an appeal to authority - the timeless purity of mathematical truth. there are countless historic examples of false rigor to justify immoral behavior as moral - it's the heart of pseudoscience.

I am flatly making a non-utilitarian argument for the morality of not making assumptions. That doesn't mean, however, that a rigorous application of utilitarian morality would not come to the same conclusions. I've made good arguments that your utilitarian equation is inadequate, and will arrive at false conclusions. You can think about those shortcomings, or argue that they aren't (as you did with your third point here), or you can write my argument off as mushy do-gooding because it's not "utilitarian".

Ignoring my criticism because it's not intrinsically utilitarian would be utilitarian. It would not, however, be rigorous.

Utilitarianism without rigor breaks down, almost inevitably. See the problem?

Math is not an authority. By this logic, all arguments based on reason are an appeal to authority. An appeal to authority is when you appeal to a human who is highly likely to be correct, but who's reasoning is unavailable for examination. https://en.wikipedia.org/wiki/Argument_from_authority

Since I presented every step of my argument, and you examined it, it is by definition not an argument by authority. It's simply an argument.

If you want to make a rigorous utilitarian case, do it. Simply pointing out some (non-)problems with the model I presented is not the same thing. All you are doing is arguing that there is more uncertainty than I believed, and then making an unjustified assumption that the uncertainty somehow supports your case.

Also, I didn't "ignore" your moral argument. I specifically asked you to make it - "What morality do you take?"

Okay, I'll give you that one. Not an appeal to authority - just a weak argument. Again, I'm saying that utilitarian morality requires rigor in order to be valid, or it risks putting the approving stamps of both morality and reason on false conclusions. There are some serious rigor problems in your original argument.

Beyond that, I do question utilitarian morality, for exactly these reasons. If it were software, it'd be a code smell. It's very easy to turn into justification for all sorts of foul things, and the track record of utilitarian morality is very ugly - like millions of dead ugly. It sure sounds good, especially if you're smart and used to being right on logical issues that don't involve squishy emotions. But it's a dangerous path.

Again, you have yet to identify a single problem that lack of "rigor" caused. I'm aware all models are incomplete. On the other hand, swooping in, declaring a model flawed without actually identifying a single problem, and alluding to some unspecified alternate morality is a little silly.

I also have no idea where you get "millions of dead ugly" applied to utilitarianism. I also don't get why you think "squishy emotions" like tribalism, desire to affiliate with high status people, or envy of others will somehow save us.

Maybe if you actually wrote down a model I'd be able to understand what you are trying to claim.

Reasonable proposal here: both of your POVs can trivially be reconciled as follows: developers are marked in some special way, such that they can trivially be separated from non-developers. Perhaps the badge is a different color.

This improves the position of everybody in the network: those who want to talk with recruiters can do so, recruiters don't have to talk with anybody who would only waste their time and there be no reason to assume that women developers are not since gender would be a strictly inferior signal to the (non-discriminary) badge color.

See, that's a great idea! The exact sort of thing needed to overcome the bias - a better signal.
Yummyfajitas seems to be using utilitarian morality in his argument, not ejecting it altogether. That's what the concern with the net number of people harmed would suggest anyway.
Not really. It looks like utilitarian morality on the surface, but it lacks a rigorous analysis of consequences (as I pointed out on at least two fronts). Utilitarian morality's bootstrap definition requires rigor in order to use it - otherwise, there's a real danger of arriving at an immoral conclusion, which means it's not utilitarian.

Putting a pig in a suit doesn't make it a gentleman.

Which gets back to Occam's Razor. Which is more likely... that this was a failure of insufficient rigor, or that it was using utilitarianism and math to appeal to authority? Given that there were multiple violations of rigor, Occam's Razor suggests that this wasn't utilitarian morality at all, but rather mere defensive rhetoric.

Of course, this doesn't imply intent - the author might not realize that his formal-sounding justification was actually rationalization, because of a failure to understand the underlying moral issue. Which is exactly how bias works in most cases.

Someone put it really well recently, in the context of racism and racist police behavior. They said racism isn't waving a Confederate flag around. Racism is looking for excuses every time the police shoot another unarmed black man. People who don't think of themselves as racist or sexist, who actually find those ideas repulsive, are actively racist and sexist all the time! This is because they don't see the bias in their own behavior.