June 2008

On the careless pursuit of trivial things

29 Jun 08
in

From Grant McCracken’s blog piece entitled “Why there will always be an anthropology”

In the Wall Street Journal today, the book review opens this way.

Consider Linda, a 31-year-old woman, single and bright.  As a student, she was deeply concerned with discrimination and social justice and also participated in antinuclear protests.  Which is more probable?  (a) Linda is today a bank teller; (b) Linda is a bank teller and active in the feminist movement.

[Psychologists Daniel Kahneman and Amos Tversky determined] that most respondents picked "b," even though this was the narrower choice and hence the less likely one. 

Shaywitz, the reviewer, says that Kahneman and colleagues have

reshap[ed] the study of economics by challenging the assumption that a person, when faced with a choice, can be counted on to make a rational decision.

I would argue that "b" is the rational decision.  It shows us the respondent working with what he knows.  We have given him a little information and he is working this information into an intelligent choice. 

That's a completely ridiculous conclusion to draw from the experiment - even statistically. You could replace 'bank teller' with 'bartender' or 'lawyer' and the result would be the same. Having primed somebody with the suggestion that Linda is socially conscious, it is actually more likely for them to think that she's active in the feminist movement than that she's a bank teller or school bus driver, because, statistically, someone likely to be be concerned with discrimination is also likely to be concerned with feminism. (This is the 'prior information' that steve postrel talks about).

Consider this re-wording of the question:

"Li Shen is 19 and earns passing grades in college. As a child, he used to draw with crayons, and played with his classmates. Which is more probable? (a) Li is studying law; (b) Li is studying law and has friends"

This is a question that is disconnected from the premise supplied (okay, that is debatable, but it is still a tenuous connection). Given that the intent of the experiment is to determine whether people will pick the more probable (read larger) set of two, it must be demonstrable that (a) the conclusion does not follow from the premise; and (b) that one of the sets is larger than the other (presumably there are law students somewhere without any friends - but this requires interpretation). Any other experimental design induces interpretation on the behalf of the subject. Let's try again:

"Which is more probable? (a) Li is studying law; (b) Li is studying law and has brown hair"

Better. But completely pointless. In fact, the experiment could have been written with the choices like this:

"Which is more probable? (a) Linda is active in the feminist movement and a bank teller; (b) Linda is a bank teller"

or even:

"Which is more probable? (a) Linda is active in the feminist movement; (b) Linda is active in the feminist movement and has red hair"

I'm willing to bet that with the last formulation, the subjects would have picked option (a) - the correct, 'rational' answer. One does not have to resort to a discussion of the context of definitions to see that this is an experiment that proves absolutely nothing.

Do Kahneman & Tversky have any excuse for having wasted perfectly good grant money on such a badly designed experiment?

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waitress power

6 Jun 08
in

you cannot see me

This is how I was seated at a restaurant recently. To my back is the door that connects the kitchen and cash register area, the primary entry and exit point for waitresses. Anyone trying to catch their attention would have an easier job if seated facing the opposite way. When questioned, my waitress claimed it was an unconscious decision to place me there, but I wonder now whether waitresses use the topology of a space to constrain their interactions with customers - what if I was a known troublemaker?

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google is (not) leaking

6 Jun 08

image stumbled across this when a co-worker got a phone call from a 216 number and was trying to find the originating city. some poor sod is going to have his/her phone spammed for something. the difference between a safe technology and a dangerous one is often merely a question of ease of use (this is why linux waits a couple of seconds before announcing that your password is incorrect). what’s troubling here is how far google is going to help your number be randomly broadcast far and wide. … and the above piece of excogitation is completely and utterly wrong. it turns that this number is one of: a component of an alternate reality game, a bunch of spammers using an MCI service called ‘IP relay’, or (as yours truly thought), a shocking example of Big Media’s uncaring violations of privacy. from shoutmouth.com: The number was found on a flash drive in a bathroom stall of a venue where Nine Inch Nails had played. The drive also contained another song off Year Zero, "Me, I'm Not", and the sound of crickets. Call the number. Once you've processed the call [sounds like something less than great went down], be sure to visit this site for further details. Expect more on this to come. The image to the side is a shot of the "spectrogram" where the number appeared. notice the complete ordinariness of the story. this could have happened. but that very ordinariness makes it suspect. this is too mundane, the story too shocking, the graphic design of the 'bureau of morality' website too well done, and, for latecomers like me, too easy to discover an explanation. i get it: nine inch nails is clever. they're cool. or someone is trying to make them look cool or clever. either way, this is an interesting way of grabbing attention. i get it again: nine inch nails is cool. here is the brilliance of the stunt: you can't tell how much of this experience was crafted. did someone really find the flash drive in that toilet? did someone really think: "just the sound of crickets? this must be some kind of code"? did someone else really figure it out for the rest of us uncomprehending fools? who, exactly, among all these people on the internet (including shoutmouth), was in the know all along? alternate reality games rely on this uncertainty. but even this uncertainty is bounded - when you choose to participate, you know, after all, that you are in the universe of the game - even if you wish to maintain a fantasy that you are in a Game. one does not, however, make fun of the game qua game. this is serious stuff for the participant, but for the occasional observer like me, it's merely confusing. that phone number ("it did belong to someone, did it not? after all, 'reverse lookup' is a related search") indexes a complex of meanings, and none of them holds primacy to me. this can only happen because of the shift of search technologies from just finding webpages to finding all sorts of other structured information. signals are being crossed – one expects to find something about a real person somewhere, but then discovers that it might have been all made up. there is something about this misinformation that subtly disturbs one’s confidence in the internet. perhaps that is part of the nine inch nails message. i get it yet again: nine inch nails is cool. clearly, this is a case of viral marketing (i'm in the design world, after all, so i should know about this stuff, shouldn't i). the idea behind viral marketing, of course, is to give a meme an air of being found, and then rely on people to pass it along as such. in this case, though, the meme has gone from being an idea that is communicated explicitly through the usual channels to being an information object in its own right (a google search query). it has gone from being communicable to being discoverable. the 'found' meme can now, really, be found, no social network needed. that bit - this emergence of the number as a popular google query - was, I hope, not crafted: because if it was, i must worship these guys, whoever they are. how interesting, then, that just as media technologies destroy increasingly more of your privacy, they themselves reveal new ways of creating misinformation, of adding noise to the signal. unlike the sufis, who have known all along, we need to understand taqiyya better.

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