CLOSE
Original image

The Surprisingly Humble Origins of Prom

Original image

Ah, prom. From the illicit temptation of underage drinking to the simple beauty of an over-corsaged wrist, the high school formal is an American tradition. But with the end of the prom season quickly approaching, our reader Laura wanted to know where exactly the dance originated. Matt Soniak's got the answer below.

Where Do Proms Come From?

Just in case you were home schooled in a survivalist compound, the prom is a semi-formal dinner and dance held at the end of a high school academic year. Today, the prom is completely inseparable from the American high school experience, and it often features fantastic displays of excess-- dresses with four or five figure price tags, transportation by stretch Hummer, weekend-long after-parties. But that's not exactly how the tradition started out. The first proms were held at colleges and were simple, home-grown events meant to teach good manners. More specifically, the dances got their start in the Northeast in the late 1800's. According to historians, one of the earliest references to prom comes from the journal of a male student at Amherst College who, in an entry from 1894, describes his invitation to, and experience at, an early prom at the nearby Smith College.

How they migrated to high schools is another story. Parents and educators thought that a (heavily chaperoned!) formal dinner and dance would instill social skills and etiquette in young adults, so they started holding their own versions of the balls for the rich and well-to-do. They even borrowed the name; "prom" is a shortened form of promenade, the march of guests at the beginning of a ball or formal event.

By the early 1900s, the prom had spread to high schools. The very early ones were like those held at colleges: the senior class, dressed in their "Sunday best," gathered in the gym for tea and light refreshments, socializing and dancing under crepe paper streamers and the watchful eyes of chaperones. But by the '30s, proms were being held nationwide. The events began to feature a banquet dinner with music provided by a local band or a record player. And in 1936, "The Junior-Senior Prom: Complete Practical Suggestions for Staging the Junior-Senior Prom," the first guide to planning and holding a prom, was published.

Up until the 1950s, proms were still being held in high school gyms. But as the country benefited from the America's post-war economy, proms began to transform into more elaborate events. Gym were abandoned for banquet halls, hotels and country clubs. Of course, the fancier venues necessitated special shopping trips for the perfect prom dress. The emergence of prom dresses, in turn, gave rise to the prom corsage. By the end of the 80s, the prom had taken on almost larger-than-life status, which it  maintains it today-- a far cry from its humble beginnings.

Original image
iStock // Ekaterina Minaeva
technology
arrow
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
Original image
iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

Original image
quiz
arrow
Name the Author Based on the Character
May 23, 2017
Original image
SECTIONS
BIG QUESTIONS
BIG QUESTIONS
WEATHER WATCH
BE THE CHANGE
JOB SECRETS
QUIZZES
WORLD WAR 1
SMART SHOPPING
STONES, BONES, & WRECKS
#TBT
THE PRESIDENTS
WORDS
RETROBITUARIES