MIT Underwear Exposé (and Sorting Hat)

Guest blogger: Lydia Andreyevna Krasilnikova ’14, MEng ’16

This excerpt from Admissions blogger Lydia Krasilnikova’s recent post points to an extraordinary flurry of analysis that documents what color underwear is most common by dorms, gender, day of week, class year,  and department.  With multiple charts and graphs, this blog post is a blast of campus culture.

A lot of socializing at MIT happens on the dorm mailing lists. One of my favorite mailing lists is Burton-Conner’s, not because of the content of the mailing list (I’ve never been on it), but because of the excellent barrier to emailing it: it is tradition, a very important rule, and a sign of respect to sign emails to the Burton-Conner dormwide social mailing list with the color of the underwear you are wearing.

This rule is a huge boon to those of us who are data-curious and kind of creepy. All MIT undergraduates, even those who have never lived in Burton-Conner, have a wealth of data on the self-reported underwear colors of people who have emailed the entire undergraduate population, which includes Burton-Conner. Reasons for emailing all undergraduates include event announcements for student groups and departments, flame wars, and occasionally lost items. In contrast, the kinds of emails sent within a dorm mailing list include, at the top of my inbox right now, parties, house meetings, and foodmobs to restaurants in Boston; decisions about when to turn off the heating for spring, invitations to test food experiments, and a memo to the person who left their clothes in the middle washer; and requests for empty gallon jugs, superglue, cooking scales, male-to-male audio cables, MIDI cables, 120V twist lock connectors, funnels, and hairdryers.

At the end of one IAP, from BMF and Destiny kitchens, my room, Cory’s room, and Random Hall desk, I downloaded and parsed all the emails that had been sent to my MIT email address. I extracted the underwear colors from the emails and I retrieved data (this part by hand, not with a script) on the people who had sent them from the MIT people directory. 417 days later I had a very bad headache, so I made pie charts from the parsed data and traced and colored them in BMF kitchen...

Beyond pie charts, we get to formulas:

There are lots of parallels between MIT and Hogwarts. Both are magical and occasionally terrifying….But we don’t have a sorting hat, so I made a sorting hat, using the most comprehensive, unbiased data available to me (which is unfortunately neither comprehensive nor unbiased). We are going to use Bayes’ Theorem, which I think, based on my 5.59 years of experience, is the very favorite theorem of the computer science part of the course 6 (electrical engineering and computer science) department and possibly also course 7 (biology)…

Bayes’ Theorem allows us to calculate what we don’t know from what we do. Formally, for an event or truth A and an event or truth B, Bayes’ Theorem is as follows:

If you were wearing purple underwear, for example, we could calculate the probability of you living in Simmons.