Game Theory Goes to Dinner
Scenario: You’re dining out with friends at an oh-so-trendy
tapas place. the group decides to order one of everything
on the menu—which includes dishes you like (mmm, cho-
rizo) and dishes you don’t (ugh, boquerones)—to share.
How do you get the most enjoyment out of the meal?
for Katherine Stange, a postdoctoral researcher in math-
ematics, the answer lies in the application of game theory.
With colleague Lionel Levine of Cornell, Stange modeled a
simplified shared-platter scenario and arrived at some sur-
prising—and some not-so-surprising—conclusions.
to operationalize the tapas quandary, the researchers
assigned point values to different foods corresponding
to their desirability from the perspective of individual
diners and defined the most enjoyable meal as the one
that racks up the highest total score. in situations where
dining partners have opposite tastes, they reasoned,
there’s no problem—both can maximize their scores. But
when diners salivate over the same dishes, that’s when
things get interesting.
one counterintuitive result: it pays to consider what your
dining partner deems the least desirable dish. Why? if i know
my dinner date will pass on pork, i can safely save the cho-
rizo for last—even though it’s one of my favorites—because i
know it’s unlikely to disappear before i’ve had a taste.
Along with Scott Sheffield of Mit, the researchers then
modeled a complex scenario with two types of hypo-
thetical diners they dubbed the “gallant knight” and
the “boorish lout.” Knights make selections that take
into account the preferences of others, while louts al-
ways gobble up their favorites first. Stange and her col-
leagues showed mathematically that boorishness isn’t
necessarily bad, though; if everyone’s trying to be gal-
lant they may actually work at cross-purposes. tell that
to the guy who gets stuck with the check.
Fantastic Voyage for Tiny Device
it used to be that the only thing that could shrink to the
size of a sesame seed and swim through your blood-
stream was the Magic School Bus. not any longer. A new
kind of electronic medical device being developed by
assistant professor of electrical engineering Ada Poon is
small enough to venture into a person’s blood vessels or
digestive system. Powered and steered remotely by way
of electromagnetic radio waves, the device has poten-
tial applications ranging from drug delivery to internal
imaging to the removal of blood clots.
the project stems from Poon’s previous research on
wireless power. “We figured out that there’s a certain
optimal frequency where we could transmit the power
efficiently to a device inside the body,” she says. this
was a major breakthrough, because the main obstacle
in creating such a device is the relationship between the
size of the device and the amount of power it can re-
ceive. By eliminating the need for bulky batteries and
transmitting power at a frequency high enough to re-
quire only a minuscule antenna, Poon and her research
team were able to create an implant that is extremely
small— 3 mm by 4 mm.
the implant’s size isn’t the only thing that sets it
apart from other devices on the market or in develop-
ment. Poon’s device can be guided with great precision,
making it ideal for handling tricky medical tasks. “the
device is placed in a magnetic field, and by driving cur-
rents on the device we can manipulate forces on them
to propel the device, so it can swim through any fluid
medium,” says Daniel Pivonka, MS ’09, a doctoral candi-
date working with Poon. their next step is to establish a
data uplink for the device—a way for it to communicate
with an external reader, sending out an alert if, for ex-
ample, it encounters an object blocking its path.
While this project may seem plenty ambitious, for
Poon it’s one of many. She estimates that this type of
locomotive device will be in clinical use in five to 10
years. in the meantime she’s already started work on a
wireless device small enough to fit inside a living cell.
—Helen Anderson, ’ 14