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Calling All Interns

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We're in the market for new interns. Stacy Conradt and Andréa Fernandes "“ formerly InternStacy and InternAndréa "“ were superstars this semester, and they'll be sticking with us as staff writers.

This is certainly a big-shoes-to-fill situation. Which is why we're filling those shoes with more feet. For the upcoming semester, we have openings for intern writers & researchers, an intern PR maven, and lots of campus reps.

If you'd like to work for the 2,518th most popular website in the United States, here are your instructions...

Intern Writer/Researcher

Job Description:
You'll spend your semester brainstorming, researching and writing stories that will appear on, like Stacy and Andréa have been doing since September.
Interview Assignment:
1) Come up with three ideas for stories. Here are links to some of our greatest hits.
2) Turn one of those ideas into a fascinating article.
3) Come up with two ideas for mental_floss quizzes. See our quiz archive for inspiration.
4) Suggest one idea for a recurring column, like Andréa's 'Feel Art Again.' We probably won't ask you (or force you) to actually write it, but you never know.
How To Apply:
Email your resume and your answers to the above questions to

Intern PR Maven

Job Description:
Work with us to improve that 2,518 ranking and increase overall awareness of mental_floss. This will include a decent amount of online research and making contacts at other thriving sites. Plus plenty of brainstorming for story ideas, giveaways, contests, etc.

Interview Assignment:
1) If you were planning a mental_floss event on your campus, what would it be called and where would you hold it? How would you make sure people attended and had a good time?
2) Pretend you've written some fascinating story (you can make up the topic, and pick an actual article from out there in the blogosphere), and convince us we should talk about it on
How To Apply:
Email your resume and your answers to the above questions to

[Writers/Researchers and PR Mavens should be willing to perform your duties for either college credit or a small stipend. You don't necessarily need to be a college student, though you must be willing to work on the cheap.]

mental_floss campus_reps

Job Description:
For pride, resume enhancement, some free t-shirts and perhaps a small budget for events, you'll introduce your school to the wonderful world of mental_floss. (But mostly for pride.) We're not yet sure what this means. Organizing trivia challenges at local bars or coffee houses? Handing out copies of the magazine?

Interview Assignment:
1) Figure out this whole campus_reps idea. What would you do if you were representing mental_floss at your school? (We'll do some thinking on it, too.)

How To Apply:
Email your resume and your answer to the above questions to

A few quick notes before we let the games begin:

1. We'll give you until the end of next week (December 21st) to apply, and our new interns should be available to start in early January.

2. Our interns can work from anywhere. We don't have much room in our NY office anyway.

3. While Stacy, Andréa and former intern Jason Plautz all made the jump from intern to contributor, that's not a given. We've been lucky that none of them turned out to be crazy. But if you're good, we'll happily ask you to stick around.

4. If you have other skills you think would work in an intern capacity -- fact-checking, copy editing, knowledge of WordPress, ergonomics expertise, patience with our nonsensical ideas for side projects -- we're happy to consider you as well. Send those pitches to

5. You should not be difficult to work with. This is probably the most important rule. Any sign of diva-ness will derail your candidacy.

6. And thanks to reader Kevin B. for suggesting we use a photo of Kenneth, the NBC Page on 30 Rock.

Looking forward to reading your submissions! Any questions, you can leave a comment or email me. It's Jason -at- mentalfloss -dot- com.

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

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Name the Author Based on the Character
May 23, 2017
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