5 ms·

I used to be really concerned and generally opposed to such biases. But after careful thought, I'm now very uncertain. I really want to know how much of this "

I used to be really concerned and generally opposed to such biases. But after careful thought, I'm now very uncertain. I really want to know how much of this "bias" is actually just an informative and useful prior. As an example, suppose you have two candidates from Princeton. One is black, the other is asian. With high probability, the asian candidate is smarter - he had to pass through a much more rigorous college admissions filter than the black person. https://news.ycombinator.com/item?id=11904256 https://news.ycombinator.com/item?id=11904256 Now given equal evaluations, it probably makes sense to hire the Asian person over the black person. (Similar reasoning suggests you should prefer an Asian to a white person.) The reason is simply that base rates matter. Bayes rule says that P(good candidate|evidence) = P(evidence|good candidate) P(good candidate)/P(evidence). The term P(good candidate) is known as the base rate - as simple arithmetic demonstrates it's important information. So assuming the base rate for various groups differs, these "biases" might actually not be biases at all - they might be informative. If we eliminate these biases from our process, we might actually make worse decisions [1]. Unfortunately this article doesn't address that question at all. See also this body of research, which suggests that many racial/sexual stereotypes are actually useful priors and improve human decisionmaking: http://www.rci.rutgers.edu/~jussim/unbearable%20accuracy%20of%20stereotypes.pdf http://www.rci.rutgers.edu/~jussim/unbearable%20accuracy%20o... I'm also curious to hear arguments about the ethics of using such information in decision making, assuming they are in fact informative. [1] For those unfamiliar with statistics, I've got a simple article here illustrating the arithmetic of base rates. Clickbait title: A gay person donates blood which tests negative for HIV. A straight person donates untested blood. Which is safer? The answer will SHOCK you. https://www.chrisstucchio.com/blog/2016/why_gays_cant_donate_blood.html https://www.chrisstucchio.com/blog/2016/why_gays_cant_donate...

eevilspock 10y ago
To get at the ethics of it, even if what you say is true, one must understand the Matthew Effect and self-fulfilling prophesy. These are just as much a force of nature as natural selection and the invisible hand. Einstein called compounding growth one of the most powerful forces in the universe. The Matthew Effect is compounding inequality over generations.
- yummyfajitas 10y ago
  Inequality isn't compounding though (at least this century). It's shrinking rapidly. http://www.maxroser.com/economic-world-history-in-one-chart/ http://www.maxroser.com/economic-world-history-in-one-chart/ https://twitter.com/MaxCRoser/status/745602914123603968 https://twitter.com/MaxCRoser/status/745602914123603968 But I'm curious though - by what mechanism will such decisions actually cause the Matthew effect? For examples in that article, it's somewhat clear - e.g., the famous mathematician becomes more famous because people notice his papers. But now, in employment, suppose I will make better decisions by favoring an equally qualified Tamil over a Bihari. How will that cause Tamil-Bihari inequality to increase at an exponential rate? Also, even if some groups do get a higher growth rate than others, why is that relevant? Concretely, what ethical or moral reason do we have for choosing these arbitrary groups to care about?
  - eevilspock 10y ago
    Neither of those links/graphs show that inequality had decreased. His argument is based on the false assumption that one-hump is more equal than two. Here are some graphs that argue the other way: http://www.newyorker.com/news/john-cassidy/pikettys-inequality-story-in-six-charts http://www.newyorker.com/news/john-cassidy/pikettys-inequali.... Note that the decrease in inequality after WW2 is due to the New Deal and other massive social welfare programs that redistributed wealth. The moment we stopped doing that inequality started growing again. The only way to counter the Matthew Effect is to change the feedback loop. The post-WW2 programs and post-civil rights movement Affirmative Action programs (coincidentally affirmed by SCOTUS today) are examples of doing just that. I'll not make an argument for the merits of desegregating society here, but the Parable of the Polygons (http://ncase.me/polygons http://ncase.me/polygons) is another example of how deliberate counteractions are the only way to change the "natural" course of things. Human culture (including evolving social mores, laws and science) is a prime example of changing the natural course of things. Laissez-faire doesn't always work. How do such decisions cause the Matthew Effect? In so many ways! But here's one to get you started: Black Americans are clearly less advantaged than white Americans. That translates to white Americans growing up in a safer environment, being better educated, having more connections to other advantaged people, not being constantly violated (I highly recommend you read Ta-Nehisi Coates's Between the World and Me) the way blacks are -- I could go on and on. So of course whites will more often be "better hires" from a pure business perspective. So more whites get hired for better jobs. So guess whose children get to live in better neighborhoods, get to go to better schools, and all the other advantages I listed earlier? That is the Matthew Effect.
rrecuero 10y ago
Nice explanation. I agree with your point. It's not natural for most people to perform statistical judgements. It's not obvious that base rates matter even in the presence of evidence. It's true as well that we should not forget that intuitive impressions of evidence are often exaggerated. However, we would do well in not forgetting other biases like the Halo Effect that may at play during any interview process.
- deleted 10y ago
  [deleted]
Zigurd 10y ago
"Biases" are a species of uninformed preference. It is really unlikely that satisfying your biases is going to lead to better decision-making. This goes for just about any mismeasure and folk wisdom, as Google has found out. Multiple dimension of Google's hiring process have been revised as they found they were getting sub-optimal results from the usual kind of "hiring people like me" approach. For example, it used to be a good bet that men made better orchestra musicians. Until they made auditioners take off their shoes and play behind a screen. You can't detect that bias without trying very hard to wash it out. If men were substantially ALL of the successful orchestral musicians, it would of course look like a completely justified "bias."
- yummyfajitas 10y ago
  First of all, base rates matter. Here's a simplified proof: Suppose you want to know if X is true. You have evidence E which is correlated with X - suppose A = P(E|X) > 0.5 and B = P(!E|!X) > 0.5. Bayes rule shows: P(X|E) = P(E|X) P(X) / P(E) = P(E|X)P(X) / (P(X)A + (1-B)P(!X)) = P(X)A / (P(X)(A+1-B) + 1-B) Differentiating this w.r.t. P(X) shows that it monotonically increases with P(X). QED. Now I'm not disputing - at all - that human biases exist. Far from it! What I'm asking is whether the behaviors discovered in this article are biases (errors that result in worse decisions) or merely accurate use of priors (using correct base rate knowledge to make better decisions). In the case of orchestras the answer is pretty clearly yes. Similarly in the case of baseball. In college admissions and lending the answer is likely to be no [1]. This article completely ignores the question! [1] https://randomcriticalanalysis.wordpress.com/2015/05/16/on-concentrated-poverty-and-its-effects-on-academic-outcomes/ https://randomcriticalanalysis.wordpress.com/2015/05/16/on-c... http://ftp.iza.org/dp8733.pdf http://ftp.iza.org/dp8733.pdf https://randomcriticalanalysis.wordpress.com/2015/11/22/on-the-relationship-between-negative-home-owner-equity-and-racial-demographics/#my_analysis https://randomcriticalanalysis.wordpress.com/2015/11/22/on-t...
  - ubernostrum 10y ago
    1. Argue that yummyfajitas is known to often be wrong, and in fact terribly wrong, thus justifying bias against acceptance of any views advanced by yummyfajitas. 2. Spread this now rationally-supported (on base rate grounds) bias among many people. 3. Find some time later that yummyfajitas' views are overwhelmingly rejected by persons reached in step 2. 4. Declare bias established in step 1 to be retroactively objectively correct after observing how yummyfajitas' posts fare with observers, and note that even yummyfajitas will not be able to argue with it, as the correctness will be demonstrated by yummyfajitas' own argument in comment above.
hackinthebochs 10y ago
The issue with this reasoning is that your "base rate" is sampled from the general population, while the population of Princeton graduates will look nothing like the general population. So the question is how informative is the base rate prior (from gen. pop.) when you have further information of Princeton graduate? You may then suggest that since we do not have a meaningful prior based on Princeton grads, it makes sense to use the gen. pop. base rate. After all the Asian still has to pass a more rigorous process to attend Princeton. But this ignores the unique barriers that the black candidate also had to pass, for example economic hardships, lack of parental and peer examples of successful college grads, all sorts of cultural issues, etc. Ultimately the question is how valuable is the gen. pop. prior given that we do know the candidates come from the population of Princeton graduates? At the very least its significantly reduced, while it may also be entirely worthless. Given these caveats and the dramatic social issues that result from using this prior to significantly bias your hiring process against black candidates, it seems like a moral imperative not to use it.
- yummyfajitas 10y ago
  The base rate I'm using isn't the population base rate at all - it's the top 25 college students base rate, sliced by race. Between 2/3 and 5/6 of black college students at the top 25 schools did not meet the usual intelligence/test score cutoffs to get in. Thus, the base rate for "exceeds normal cutoff" for a black student at Princeton is in the range of 1/6-1/3. (In contrast, the base rate for Asian students is likely higher. The base rate for athletes and the children of large donors is likely lower, for much the same reason.) The various factors you discuss might be causes for why most blacks don't exceed the normal cutoff. But that doesn't mean that ignoring it will be an optimal decision for a person attempting to hire high intelligence/test score individuals.
  - hackinthebochs 10y ago
    If you're just going by entrance GPA/test scores, then I would still question the usefulness of that base rate after the person has graduated and also passed whatever screening process your company has. GPA/test scores surely correlate with intelligence, but they can be gamed to a large degree especially by students with the means and motivation (the typical Asian student). As far as I've seen GPA/test scores only correlate with success in the first year or two of college. So again we're left with the question of how meaningful is your base rate at all? I don't think there is any reason to think it provides any information that isn't completely overshadowed by the fact that the person graduated, their college GPA, and their success in your own screening. Using such dubious priors is biasing your decision making based on unjustifiable assumptions, and will likely end up with worse decision making.

eevilspock 10y ago

To get at the ethics of it, even if what you say is true, one must understand the Matthew Effect and self-fulfilling prophesy. These are just as much a force of nature as natural selection and the invisible hand. Einstein called compounding growth one of the most powerful forces in the universe. The Matthew Effect is compounding inequality over generations.

yummyfajitas 10y ago
Inequality isn't compounding though (at least this century). It's shrinking rapidly. http://www.maxroser.com/economic-world-history-in-one-chart/ http://www.maxroser.com/economic-world-history-in-one-chart/ https://twitter.com/MaxCRoser/status/745602914123603968 https://twitter.com/MaxCRoser/status/745602914123603968 But I'm curious though - by what mechanism will such decisions actually cause the Matthew effect? For examples in that article, it's somewhat clear - e.g., the famous mathematician becomes more famous because people notice his papers. But now, in employment, suppose I will make better decisions by favoring an equally qualified Tamil over a Bihari. How will that cause Tamil-Bihari inequality to increase at an exponential rate? Also, even if some groups do get a higher growth rate than others, why is that relevant? Concretely, what ethical or moral reason do we have for choosing these arbitrary groups to care about?
- eevilspock 10y ago
  Neither of those links/graphs show that inequality had decreased. His argument is based on the false assumption that one-hump is more equal than two. Here are some graphs that argue the other way: http://www.newyorker.com/news/john-cassidy/pikettys-inequality-story-in-six-charts http://www.newyorker.com/news/john-cassidy/pikettys-inequali.... Note that the decrease in inequality after WW2 is due to the New Deal and other massive social welfare programs that redistributed wealth. The moment we stopped doing that inequality started growing again. The only way to counter the Matthew Effect is to change the feedback loop. The post-WW2 programs and post-civil rights movement Affirmative Action programs (coincidentally affirmed by SCOTUS today) are examples of doing just that. I'll not make an argument for the merits of desegregating society here, but the Parable of the Polygons (http://ncase.me/polygons http://ncase.me/polygons) is another example of how deliberate counteractions are the only way to change the "natural" course of things. Human culture (including evolving social mores, laws and science) is a prime example of changing the natural course of things. Laissez-faire doesn't always work. How do such decisions cause the Matthew Effect? In so many ways! But here's one to get you started: Black Americans are clearly less advantaged than white Americans. That translates to white Americans growing up in a safer environment, being better educated, having more connections to other advantaged people, not being constantly violated (I highly recommend you read Ta-Nehisi Coates's Between the World and Me) the way blacks are -- I could go on and on. So of course whites will more often be "better hires" from a pure business perspective. So more whites get hired for better jobs. So guess whose children get to live in better neighborhoods, get to go to better schools, and all the other advantages I listed earlier? That is the Matthew Effect.

rrecuero 10y ago

Nice explanation. I agree with your point. It's not natural for most people to perform statistical judgements. It's not obvious that base rates matter even in the presence of evidence. It's true as well that we should not forget that intuitive impressions of evidence are often exaggerated. However, we would do well in not forgetting other biases like the Halo Effect that may at play during any interview process.

deleted 10y ago
[deleted]

Zigurd 10y ago

"Biases" are a species of uninformed preference. It is really unlikely that satisfying your biases is going to lead to better decision-making. This goes for just about any mismeasure and folk wisdom, as Google has found out. Multiple dimension of Google's hiring process have been revised as they found they were getting sub-optimal results from the usual kind of "hiring people like me" approach. For example, it used to be a good bet that men made better orchestra musicians. Until they made auditioners take off their shoes and play behind a screen. You can't detect that bias without trying very hard to wash it out. If men were substantially ALL of the successful orchestral musicians, it would of course look like a completely justified "bias."

yummyfajitas 10y ago
First of all, base rates matter. Here's a simplified proof: Suppose you want to know if X is true. You have evidence E which is correlated with X - suppose A = P(E|X) > 0.5 and B = P(!E|!X) > 0.5. Bayes rule shows: P(X|E) = P(E|X) P(X) / P(E) = P(E|X)P(X) / (P(X)A + (1-B)P(!X)) = P(X)A / (P(X)(A+1-B) + 1-B) Differentiating this w.r.t. P(X) shows that it monotonically increases with P(X). QED. Now I'm not disputing - at all - that human biases exist. Far from it! What I'm asking is whether the behaviors discovered in this article are biases (errors that result in worse decisions) or merely accurate use of priors (using correct base rate knowledge to make better decisions). In the case of orchestras the answer is pretty clearly yes. Similarly in the case of baseball. In college admissions and lending the answer is likely to be no [1]. This article completely ignores the question! [1] https://randomcriticalanalysis.wordpress.com/2015/05/16/on-concentrated-poverty-and-its-effects-on-academic-outcomes/ https://randomcriticalanalysis.wordpress.com/2015/05/16/on-c... http://ftp.iza.org/dp8733.pdf http://ftp.iza.org/dp8733.pdf https://randomcriticalanalysis.wordpress.com/2015/11/22/on-the-relationship-between-negative-home-owner-equity-and-racial-demographics/#my_analysis https://randomcriticalanalysis.wordpress.com/2015/11/22/on-t...
- ubernostrum 10y ago
  1. Argue that yummyfajitas is known to often be wrong, and in fact terribly wrong, thus justifying bias against acceptance of any views advanced by yummyfajitas. 2. Spread this now rationally-supported (on base rate grounds) bias among many people. 3. Find some time later that yummyfajitas' views are overwhelmingly rejected by persons reached in step 2. 4. Declare bias established in step 1 to be retroactively objectively correct after observing how yummyfajitas' posts fare with observers, and note that even yummyfajitas will not be able to argue with it, as the correctness will be demonstrated by yummyfajitas' own argument in comment above.

hackinthebochs 10y ago

The issue with this reasoning is that your "base rate" is sampled from the general population, while the population of Princeton graduates will look nothing like the general population. So the question is how informative is the base rate prior (from gen. pop.) when you have further information of Princeton graduate? You may then suggest that since we do not have a meaningful prior based on Princeton grads, it makes sense to use the gen. pop. base rate. After all the Asian still has to pass a more rigorous process to attend Princeton. But this ignores the unique barriers that the black candidate also had to pass, for example economic hardships, lack of parental and peer examples of successful college grads, all sorts of cultural issues, etc. Ultimately the question is how valuable is the gen. pop. prior given that we do know the candidates come from the population of Princeton graduates? At the very least its significantly reduced, while it may also be entirely worthless. Given these caveats and the dramatic social issues that result from using this prior to significantly bias your hiring process against black candidates, it seems like a moral imperative not to use it.

yummyfajitas 10y ago
The base rate I'm using isn't the population base rate at all - it's the top 25 college students base rate, sliced by race. Between 2/3 and 5/6 of black college students at the top 25 schools did not meet the usual intelligence/test score cutoffs to get in. Thus, the base rate for "exceeds normal cutoff" for a black student at Princeton is in the range of 1/6-1/3. (In contrast, the base rate for Asian students is likely higher. The base rate for athletes and the children of large donors is likely lower, for much the same reason.) The various factors you discuss might be causes for why most blacks don't exceed the normal cutoff. But that doesn't mean that ignoring it will be an optimal decision for a person attempting to hire high intelligence/test score individuals.
- hackinthebochs 10y ago
  If you're just going by entrance GPA/test scores, then I would still question the usefulness of that base rate after the person has graduated and also passed whatever screening process your company has. GPA/test scores surely correlate with intelligence, but they can be gamed to a large degree especially by students with the means and motivation (the typical Asian student). As far as I've seen GPA/test scores only correlate with success in the first year or two of college. So again we're left with the question of how meaningful is your base rate at all? I don't think there is any reason to think it provides any information that isn't completely overshadowed by the fact that the person graduated, their college GPA, and their success in your own screening. Using such dubious priors is biasing your decision making based on unjustifiable assumptions, and will likely end up with worse decision making.