Avinash Dixit is one of my favorite economists, in part because he has a trait that is extremely rare among economists: a good sense of humor.
In a recent paper, Avinash explores a decision problem drawn from Seinfeld. When the contraceptive sponge that Elaine favors is taken off the market, she scours the city buying up as many sponges as she can; but with finite supply, she faces a difficult decision as to which men are worthy of her precious sponges.
Avinash uses the tools of stochastic dynamic programming to help Elaine?solve her problem.
For this important contribution, I suspect Elaine would conclude that Avinash is himself spongeworthy.
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Finally we have the answer to students’ eternal question of their math teachers: “Why are we learning this?”
When products get rare or expensive, then consumers may substitute goods. Supermarket sponges are probably less than a hundreth the cost of a medical sponge.
Sponges are a cheap commodity: Synthetics, Rainbow colored, Natural Sponge, Mediteranean Organic Sea Sponges, Challenger Deep-Sea sponges.
Maybe Elaine should substitute a natural organic custom home made sponge. A generation ago women made homemade tampons from old rags. IT just has to sop up sperm, and sperm are single minded and not too adaptable to hostile conditions…unless it were MacGyver Sperm.
I always thought that episode – and Elaine – was pretty stupid. There are lots of other contraceptives besides sponges she could have used.
But, then again, Seinfeld was a pretty stupid show in general.
Thank you for reminding me to pay the tuition on my college algebra class.
Drill-Baby-Drill Drill Team,
Not many kitchen or sea sponges come with nonoxynol-9 …
sigh…
Some complicating factors:
(a) one-sponge-per-day assumption?
(b) Elaine can adjust her utility ad hoc: “Do something about those sideburns?” “Clean your bathroom, including the tub?”
It seems to me that the sponges would be used on the less worthy men–after all, if there is a risk of pregnancy, you wouldn’t want it to be with a loser (presumably).
Thus, if she encounters the perfect man, he is not sponge-worthy…but rather worth risking pregnancy in order to have a go.
I think it would work similarly with men if the shortage was condoms. If we were fortunate enough to have a large supply of willing women, we’d most certainly want to make sure that we weren’t procreating with someone that looks like, uh, trouble. But if we had a chance to have a go at, say, Jennifer Aniston, I think most men, condom or not, would go for it.
If a pregnancy results–hey! Jennifer Aniston is my baby mama!
And if pregnancy does not result–hey! I got to have sex with Jennifer Aniston!
Thinking Man:
I used to know a woman (a biologist) who believed that, by virtue of our contraception methods, we were genetically selecting for the traits of carelessness, impulsiveness, and physical clumsiness.