What does it mean for an algorithm to be fair?
jeremykun.com
jeremykun.com
"these algorithms are trained on historical data, and poor uneducated people (often racial minorities) have a historical trend of being more likely to succumb to predatory loan advertisements"
to
"Even if this is the most common question being asked on Google [..] this shows that algorithms do in fact encode our prejudice"
It's hard to make the case for prejudice when the example involves historical data, so the author weasels in an unrelated example to make the case that there is prejudice.
So which is it? There are correlates to credit worthiness which are indeed illegal, allegedly to correct bias. But the legal arguments have moved away from the concept of bias and now squarely focus on impact. See the recent Supreme Court decision on disparate impact for instance.
This seems to be the author's point of view to:
"Why is this ignorant? Because of the well-known fact that removing explicit racial features from data does not eliminate an algorithm’s ability to learn race. If racial features disproportionately correlate with crime (as they do in the US), then an algorithm which learns race is actually doing exactly what it is designed to do!"
So for the author, anything that affects one ethnic group differently is racist, whether or not it is born by the data. Prejudice or bias are irrelevant to his definition.
But then why focus on race? No scoring algorithm is perfect, and some people are always going to be shortchanged. So why not just declare by fiat: let's ignore people's height, it's height-ist. Height correlates to income and to credit worthiness. Even if you remove height from the data, your algorithm will end up picking correlates which can become a proxy to height... and the same will be true with virtually any attribute you can think of. So why race?
This second issue seems harder to resolve, because it will require lawmakers to clearly articulate a "bright line" law in the language of the algorithm itself. As the article acknowledges, algorithms can "learn" race, even if race is not an explicitly defined explanatory variable.
Looking forward to part two.
Edit: Why race? Because it's an obvious and easy example. I believe the author would be on board with your height example.
If the author is on board with height, I can take him down all the way to a reductio where you give everyone the exact same credit terms.
I can very much appreciate your reductio argument, but if i had to wager, that's the way we're headed. Seems like aspiring lawyers should start cracking open the ML textbooks, because that case is a pandora's box.
"defensible" is a weasel word.
It goes back to the old "correlation vs causation"
Machine learning choose the "shape" of a decision surface. Optimizing parameters of that surface may be defensible, or may nor be. Your algorithm may learn that people with my skin color, or who live in my neighborhood, on have a certain average behavior on your objective function.
I would word your #1 and #2 as (1) baseless prejudice that midjudges people in general, (2) statistical prejudice that misjudges many individuals.
But it's still a leap to treat me as the "average" in that group, instead of judging me on the content of my character. What guided your choice of parameters? Even if you did the best within practical limits, it still may be unfair.
Regarding impact: It could well be argued that current-day impact is the result of prejudice operating in the past. The interaction of society, economics, and demographics are complex. Hopefully, we'll just muddle through, somehow.
> Hopefully, we'll just muddle through, somehow.
This is not a good enough answer for the people who are actually being hurt, now. For these people, it's not an abstract problem.
That closure is "Harrison Bergeron"... but one man's modus ponens is another's modus tollens.
The question is what counts as fair. I'm not saying disparate outcomes is necessary or sufficient, though it receives a lot of attention. Even if we could quantify which disparate outcomes are adverse, it's not obvious how to design algorithms that meet those criteria.
I'm interested in a little thought experiment:
1. for the sake of this algorithm there are two people: a white person and black person
2. race and other "irrelevant factors" aren't recorded or used
3. these people are except for race, otherwise identical
4. how can the algorithm discriminate between them?
It seems tautological that lacking race as a feature to discriminate with the algorithm won't be able to successfully discriminate, right?
So how does the discriminatory information somehow bleed into the system such that it negatively affects two otherwise identical (or practically so) people?
I'm not trying to defend the algorithm as the perfect arbiter or anything. I'm just honestly a little confused. Is it that the irrelevant factors are actually recorded somehow, but shouldn't be?
He is thus suggesting that even given genuine group differences, different group outcomes are intrinsically unfair if the grouping happens to be race.
I would encourage to check out some of the papers at the FAT-ML workshop which was co-located with ICML. I don't think researchers are making that assumption.
In addition, race was used as an example because it is one of the sensitive attributes. The decision on what makes an attribute sensitive is based on deep discussions by society. The author of the blog post wants to communicate two points - (1) Algorithms can discriminate and (2) There is a need to understand HOW algorithms discriminate.
As an overly simplistic example: someone might point out that your algorithm's negative impact applies 75% of the time to racial minorities. There will be a political shit storm if that is the end of the story. But if you can show that the segmentation is actually 99.8% people in prison, you basically prove your algorithm is politically acceptable and pass the buck of outrage on somewhere else.
I agree that this stuff is hard to nail down in a logically consistent way. But, this stuff has a history. Group discrimination has had horrible results in the past. This is our sloppy duct tape fix. Algorithm based selection is now challenging the assumptions.
If an admissions officer offers places only to handsome, white men from upper class backgrounds, we see that as unfair because these things have no direct impact on their value as students. He's an ass. For the sake of argument, imagine an algorithm arrives at the same conclusion as the ass. Our moral instinct is confused. Societal impact is similar.
There certainly is something dehumanizing about selection algorithms making decisions. I hate buying insurance or being assessed for loans. It feels bad.
Basically, I don't think you can reductio ad absurdum this argument away. There are inconsistencies in our moral sentiments.
Any imperfect criterion will always exist at the expense of some group of people (tautologically, the group of people to which the criterion is unfavorable). What difference does it make, ethically, if the group happens to be identifiable?
If an insurance company had no data, they would have to give everyone the average premium. Egality of ignorance.
See, for example, this long thread where this conflation is made: https://news.ycombinator.com/item?id=8368876
The claim is logically false - you can't prove a normative claim without a normative premise. In my example above, one possible normative hypothesis would be "and it's morally wrong to use incorrect premises to make decisions" (or possibly "it's morally wrong to use incorrect racial premises to make decisions").
Now our algorithms are revealing that underlying positive claim (e.g., "racial stereotypes are incorrect") might not be true either.
This is confusing, and rightly so - it demonstrates our entire belief system was predicated on nonsense. Hopefully we'll actually respond with some useful analytical philosophy.
But if a neurologist proves that sexual orientation is acquired during childhood, are we going to throw out gay rights?
In any case, I think these moral arguments are (a) more of a counterpoint argument to the pseudoscientific racism of the Nazis and their predecessors and (b) more about innate genetic potential than socio-cultural traits.
I think the stronger moral argument is about equality of opportunity and (hat tip to a charmingly american ethos) individual merit. The idea is that it is more moral to judge people by their personal merit, rather than profiling and assuming even if that gives you a better chance of being correct.
For example, take health insurance. No matter if it's voluntary or mandatory, at root it's a system where healthy people pay for sick people. If you're healthy today, you still pay because you might get sick tomorrow. But if sickness were 100% knowable in advance, then healthy people would have no incentive to participate, or even to set up such a system in the first place! The system only works due to a lack of knowledge, and advanced machine learning algorithms could easily break it.
The root of the problem is that the market-efficient way to redistribute resources is not the way that leads to the most happiness. (The technical term is "diminishing marginal utility of money".) We need to give free stuff to those who are statistically less likely to win it in competition. If our machine learning algorithms disagree, that just means they're optimizing for the wrong criteria.
The root of your argument seems to be that we need to trick people into helping other people. That seems to be an ultimately futile strategy. Better to really convince them.
Redistrubution by trickery, or even by force, might still be better than no redistribution at all. I'm pretty confused about this issue myself, don't have any clear answers.
To me, such an upside vastly outweighs the "downside" of driving a spike through the heart of the health insurance industry. (This also points out how, if you see a problem with "market-efficient" distribution, perhaps the problem is with applying market principles to everything and not with the machine learning algorithms.)
If you are asking the question "is this algorithm fair?", you are asking a political question.
Any discussion of inequality in the modern world that does not explicitly include racism is necessarily deficient.
I think the point is so that it can bludgeon home that our work as technologists has serious social implications, and that we can't dodge them, even though this stuff is ridiculously difficult.
How does mentioning race make the topic unnecessarily politicized?
Is there really a strong contingent that believes algorithms that discriminate against people based on their race should be implemented and deployed?
Automated discrimination is pretty frightening and we should avoid implementing such systems. Further, we should be aware it can occur and should do what we can do detect and fix any occurrences.
For example, if hair length is societally taboo for gender prediction and I make an algorithm that uses a "politically correct" determination using XY chromosomes, I have also made an algorithm that correlates with hair length. Moreover, if I try to statistically correct my algorithm so that it does not correlate with hair length, I end up with an algorithm that works on the tiny leftover residual created by people who buck the trend, i.e. one that's much more likely to be wrong.
Algorithms find both correlational and causal factors. If 9/10 men are from Mars, and you tell me you're from Mars, it is often via correlation that the algorithm labels you a man. You are not allowed jump to the assumption that, say, the drinking water on Mars is turning people into Men.
Is only true in a system without feedback. If your response to observations can affect the subjets under study, then acting on the correlation can change the correlation.
If you decide to offer everyone in Nairobi a $million to join your super-jumpers space-exploration program, because Nairobi correlates to high jump ability, you will find that low jumpers will flood into Kenya to collect on your offer.
Whereas, no matter how much you abuse the fact that gravity make things fall, you aren't going to make gravity stop making things fall.
Correlation and causation have the same predictive power.
The example he gave is very common:
Whenever 2 independent factors contribute (casaully) to an effect, both factors are correlated to each the effect, but are not in generla (well) correlated to each other.
Instead of talking about "algorithm fairness", it appears to be talking about "algorithm equality", or alternately "algorithm legal-non-descrimination".
I'd expect one could just avoid feeding an algorithm data about enumerated protected classes (for jurisdictions where such a thing exists) and be done with it.
Avoiding non-protected-class data that is correlated with protected-classes seems almost contradictory: you'd need to feed the algorithm data about protected classes so it could determine the correlation, and then apply the inverse correlation to to the protected classes.
I'm not even sure such a thing is possible to do correctly, though I suppose what I've described is simply a techno implementation of affirmative action.
If the numbers show that poor people are more likely to respond to payday loan advertisements, then that's what the numbers show. If the businesses are truly predatory then they should be regulated. It doesn't make sense to show ads for them to people who are statistically unlikely to respond to them, nor does it make sense to show poor people ads for institutions that are statistically unlikely to grant them loans. Algorithms aren't the problem here, the nature of the businesses is.
And in fairness, I notice that when I watch certain tv shows late at night I'm much more likely to see payday loan ads than when I watch during prime time. I've long suspected that this is because the kind of person who is watching "30 Rock" re-runs at 1am is less likely to be employed and more likely to need a payday loan. So if it's fair for a media buyer to select audiences that are most likely to purchase a product, why is it unfair for an algorithm to do it?
The article makes the point that algorithms are opaque and people often can't explain exactly why a decision was made. That's fine, as long as the results can be shown to be accurate with out of sample testing. It's good to understand why, but it isn't always necessary. The point of using advanced statistical modelling is to expand our level of capability beyond what our brains can easily perceive. The ability to draw reliable inferences from tens of millions of data points is a very powerful and wonderful thing, quite a leap for evolved monkeys who use lobes of fat to perform calculations. It's new, it's different, and it's definitely worrying. But the sooner we can adapt, the better off we'll be as a society.
[1] in this case "large" probably means two or three orders of magnitude larger than you were thinking
If I charge someone extra for car insurance because he shares dozens of innocuous traits with other people who get in wrecks, I am not discriminating based on sex. If some algorithm can accurately predict the sex of that person by the same data, I am still not discriminating based on sex.
If I target blacks with predatory loan advertisements because that demographic is on average more susceptible to those ads, then I am discriminating based on race.
If I target an individual because they share dozens of innocuous traits with other people who fall for predatory loan advertisements, I am not discriminating based on race. If some algorithm can accurately predict the race of the individual based on the same data, I am still not discriminating based on race.
The software is less biased than a human because it has no concept of race. Even if the data can be used to accurately predict the race of an individual, it does not matter. The program will not spontaneously recognize the concept of race and then discriminate based off of it. If some trait correlates with race, that's because reality is biased, not the math, algorithm, company, or implementer.
It is not the responsibility of programmers to make their algorithms less accurate so ideologues can live in a fantasy world.
For example, most people who have an account throwawayXXX on HN are using it temporarily to say something. However, I actually kept one such account for a long time. My username is an innocuous trait, but you're discriminating if you assume my motives and behavior will be like most of the other throwaway accounts, just based on my username.
That said, I believe unfair discrimination is unavoidable in life because we can't always wait around to see what an individual's behavior will be before we discriminate fairly. We couldn't function without stereotypes and assumptions. And so, while still unfair because of the potential for unjustified penalties, it's much better to look at many variables than it is to look at one or two.
That said, I believe unfair discrimination is unavoidable in life because we can't always wait around to see what an individual's behavior will be before we discriminate fairly. We couldn't function without stereotypes and assumptions. And so, while still unfair because of the potential for unjustified penalties, it's much better to look at many variables than it is to look at one or two.
Then you think machine learning is the best solution that exists?
When you search Google, you get a mostly impartial set of results, but then you need to choose the most relevant from the top 10. Without Google, you'd visit far fewer websites based only on your accumulated experience. Without a human to filter through the top 10, you'd have to systematically read webpages in order until you found what you wanted. Maybe the example is a bit stretched, but machines and humans cooperating seems to work well, even right on the HN front page, or in the browser spellchecker as I type this message (apparently HN is not a word).
When we ban prejudice we are saying (IMO) two things. (2)It is unfair to the point of being illegal to assume that because one is black (old, transexual..), one is unfit to do a job, attend a university or somesuch. (2) It is harmful to society when such prejudice is widespread. It alienates or devalues a group and perpetuates social features we don't like.
I think for insurance, loans and such there is a sort of special allowance because these industries need to be biased and their bias, being cold and calculated is not unfair. They also don't specifically discriminate on racial/gender/etc lines and so they were never part of any particular anti discrimination effort.
Insurance companies particularly can work around any specific restrictions by substituting banned variables for allowable ones.
By hiring one person and not another, you are always discriminating. This kind is clearly considered in the "fair" range since it's directly relevant to the thing you are selecting for.
Which kind of discrimination are insurance companies doing?
Anyway, algorithims are far more commonly used today so the "problem" is bigger. Also, I think they are the sort of leak in the anti-discimiation logic. I mean there might not be any political campaigns dedicated to the right of the 22-30ag.1-2yrsedu.PSTC.QXRT statistical cluster, but that cluster may is discriminated against. The discrimination is impactful. It may mean they pay higher interest or insurance fees. They may be denied a lease. Non trivial impacts.
Is it fair? As the title here points out, biases & prejudices seems like a nonsensical vocabulary to use when it is based on "facts."
This is all tricky stuff. Paypal identified me at some point as "high risk." They have frozen €35 and they have reversed transactions made by me. Not uncommon. It happened because I happened to share some characteristics with some fraudsters. They aren't race, but they are not any different (from a common sense morality perspective) then being the same race as a fraudster.
I'm not sure where I'm going with this. I don't really understand it, but I don't think the relationship to legally prohibited prejudice is nonsensical.
But, I do think this can get really tricky, socially. In some places mandatory insurance can be very high. Say a group (lets go with minority men 18-25, sounds plausible) are essentially banned from driving by unaffordable prices 5-10X the average premium. This is not unrealistic. They are disadvantaged in society because of their race and age. Even if you call it fair because it's a optimal, or rational or whatnot, we have the societal impact of disadvantaging people from birth. I think it's immoral.
On the one hand, this question explodes into the "general purpose AI" literature. Less Wrong actually originated from a smaller community of people asking what did it mean for AI to be "friendly" to humans, very abstractly.
On the other hand, there's "good citizenship" desiderata. Maybe Hubert Dreyfus is correct and there can't be general AI, but the fact of the matter is that our actor-networks (as in Latour) are already crowded with algorithms and machines. What does it mean for a machine to be accountable, dependable, reliable, and yes, fair?
An image classifier should be invertible -- if we're consistently getting that black men look like apes, we should know what the machine thinks an ultra-archetype ape is. Interestingly, this has been the focus of a lot of research since I took that NN class in college back in 2001 -- we're able to visualize hidden layers now.
A credit scorer should be consistent with some wider sense of credit worthiness, sure. It should be possible to increment your credit score, at the margin, with marginal changes to (real, important) inputs, rather than have it place you in a brittle "unreliable" type. You should be able to dig yourself out of debt.
All of these are kind of domain specific, but I haven't spent much thought on it. It seems to me that there are some general characteristics (invertibility, smoothness across key controls) that should be identifiable.
Only tangentially. It was literally the next stage of Yudkowsky's blogging on Overcoming Bias, which substantially attracted as its initial commenters people from the SL4 mailing list, which dealt with many topics of transhumanist interest, including friendly AI.
(Off-topic, but your username is the name of an old western as well as the name of one of my favorite Irish reels.)
It's not enough to have a course. You have to take it seriously.
This particularly applies given the "reality" that we're talking about here is human interaction and questions as to which groups get what when, i.e. politics.
If you know where someone has their hair cut and styled, and where they attend their religious services, if any, you can probably guess with good confidence how they would self-report their race.