Bias, generalization and stereotypes: A half-baked lesson in Ethics

["Subbarao Kambhampati" <rao@asu.edu>]

[[extra-curricular]]

[ACM suggests that some percentage of CS courses should be spent on discussing
ethics. May be this will fill that role... ]


Inductive  generalizations are what allow the
organisms with their limited minds to cope with the staggering complexity
of the real world. Faced with novel situations, our ancestors had to
make rapid "fight or flight" decisions, and they had to do biased
learning to get anywhere close to survival. So, we can't really

seriously ask people not to generalize or not to have biases!

The problem of course is where does this leave us vis-a-vis
stereotypes--the "all Antarciticans are untrustworthy", "all
Krakatoans are smelly" variety. Afterall, they too are instances of

our mind's highly useful ability to induce patterns from limited
samples. 

So, what, if any, is the best computational argument against stereotyping? One
normal argument is that the stereotype may actually be wrong--in

otherwords, they are actually wrong (non-PAC) generalizations, either
because they are based on selective (non-representative) samples, or
because the learner intentionally chose to ignore training samples

disagreeing with its hypothesis.  True, some 
stereotypes--e.g. "women
can't do math", "men can't cook" variety--are of this form.

However, this argument alone will not suffice, as it leaves open the
possibility that it is okay to stereotype if the stereotype is

correct. (By correct, we must, of course, mean "probably approximately
correct," since there are few instances where you get metaphysical
certainty of generalization.)

What exactly could be wrong in distrusting a specific Antarcitican because

you have come across a large sample of untrustworthy Antarciticans?

I think one way to see it is perhaps in terms of "cost-based
learning". In these types of scenarios, you, the learning agent, have

a high cost on false negatives--if you missed identifying an
untrustworthy person, or a person who is likely to mug you on a dimly

lit street, or a person who is very likely to be a "bad" employee in

your organization, your success/survival chances slim down. At the
same time, the agent has much less cost on false positives, despite
the fact that the person who is classifed falsely positive by your
(negative) stereotype suffers a very large cost. Since the false

positive *is* a member of the society, the society incurs a cost for
your false positives, and we have the classic case of individual good
clashing with societal good.

This then is the reason civil societies must go the extra mile to

discourage acting on negative stereotypes, so we do not round up all
antarciticans and put them in bootcamps, or stop all Krakatoans at
airport securities and douse them with Chanel 5.  And societies, the

good ones, by and large do, or at least try to do. The golden rule,

the "let a thousand guilty go free than imprison one innocent", and
the general societal strictures about negative streotypes--are all
measures towards this. 

You need good societal laws precisely when the individual

good/instinct clashes with the societal good.

So, you are forced to learn to sometimes avoid acting on the highly

efficient, probably PAC, generalizations that your highly evolved
brain makes. I think. 

Yours illuminatingly... ;-)
Rao

Epilogue/can skip:

It was a spring night in College Park, Maryland sometime in
1988. Terrapins were doing fine.  The Len Bias incident was slowly
getting forgotten.  It was life as usual at UMD. About the only big

(if a week-old) news was that of a non-caucasian guy assaulting a
couple of women students in parking lots.  I was a graduate student,
and on this particular night I did my obligatory late-evening visit to

my lab to feign some quality work. My lab is towards the edge of the campus;

just a couple more buildings down the Paint Branch Drive, and you get
to the poorly lit open-air parking lots. 

On that night I parked my car, walked down the couple of blocks to my
lab, only to remember that I left a book in the car. So, I turned, and

started walking back to the parking lot. As I was walking, I noticed
that this woman walking in front turned a couple of times to look back at me. I remembered
that I had passed her by in the opposite direction. Presently I

noticed her turning into the cryogenics building, presumably her
lab. As I passed by the cryo lab, however, I saw the woman standing
behind the glass doors of the lab and looking at me. 

Somewhere after I took a few more steps it hit me with lightning

force--I was a false positive! The woman was basically ducking into
the lab to avoid the possibility that I might be the non-caucasian

male reportedly assaulting campus women. I knew, at a rational level,
that what she was exhibiting is a reasonably rational survival

instinct. But it did precious little to assuage the shock and
diminution I felt (as evidenced by the fact that I still remember the
incident freshly, after over 15 years.). There is no substitute
for assessing the cost of false positives than being a false positive

yourself sometime in your life...

--------------
     ....not to make up your minds, but to open them. 
    To make the agony of decision-making so intense that  
    you can escape only by thinking. 

 
                        -Tag line from Columbia School of Journalism Seminars 

   "Induction  extends your expectation, not your experience"