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The Quick 8: Eight Monetary Misprints

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You may have heard that a batch of new $100 bills was recently misprinted (and if you haven’t, check out #1). It may be the latest monetary mishap, but it’s certainly not the only one - here are a pocketful of other misprints that may be lurking in your wallet, including a couple of stamps.

1. More than a billion of the new $100 bill are being recalled because the new security features tripped up the printing presses a bit, causing some of the bills to be creased and print incorrectly.

2. The Del Monte Note. Imagine the surprise of an Ohio college student when he made a routine stop at an ATM and received a $20 bill with a Del Monte banana sticker affixed to it… except it wasn’t actually just affixed, it was printed in the bill, as evidenced by the bill’s serial number partially stamped across the sticker. The student knew what he had his hands on, because he sold it on eBay for $10,100 in 2003. It was purchased by a collector named Daniel Wishnatsky, who in turn sold it for $25,300.

3. The Inverted Jenny stamp. The 1918 Inverted Jenny is probably the most famous stamp error ever made – and one of the most valuable. The plane on the stamp represented the Curtiss Jenny plane which was being used for the first-ever airmail services. A few sheets of the stamps were printed with the center image of the plane upside down, but only one that we know of made it past the Post Office. The sheet was later split up into blocks and singles. If you spot one, you’re definitely not going to want to put it on your water bill – a single easily goes for a half mil while a block of four took nearly $3 million at an auction in 2007.

4. Rush Hour 2 money. OK, it wasn’t real money, but that was kind of the problem. When the Jackie Chan and Chris Tucker movie was filming in Las Vegas, they shot a scene that involved an explosion of money. The bucks were bogus, of course, but that didn’t stop onlookers from grabbing up a souvenir when the money exploded in their direction. The fakes were so good that some people were able to go into nearby shops and spend them. The Secret Service ordered the studio that made the money to cease production of such authentic-looking currency.

5. Chilean 50-peso piece. It’s not just the U.S. that misprints money – in 2008, the mint in Chile produced thousands of 50-peso coins that deemed the country “Chiie.” It cost the mint director his job.
6. The Gronchi Rosa stamp. This Italian stamp was issued in 1961 to commemorate then-president Giovanni Gronchi’s trip to South America. It wasn’t until after the stamp had been issued that it was discovered that the artist had made a mistake on the boundaries between Peru and Ecuador. A new version was issued, but the error stamp is the one that’s in high demand, of course – it’s worth about $1,200 today.

7. Wisconsin quarter. If you’re one of those people who collect all 50 of the state quarters, check out your Wisconsin coin. There’s an ear of corn on the quarter that contains an extra leaf. That extra leaf is worth about $1,100 in mint condition.

8. Arrovo bill. A few years ago, the Central Bank of Philippines made a pretty embarrassing typo – it doesn’t get much worse than misspelling the name of your president. The 100-piso banknote should have spelled the name of the president as Gloria Macapagal Arroyo, but instead named her as “Arrovo.” Although the bill was recalled as soon as possible, there are a few thousand still estimated to be in circulation.

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
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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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One Bite From This Tick Can Make You Allergic to Meat
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We like to believe that there’s no such thing as a bad organism, that every creature must have its place in the world. But ticks are really making that difficult. As if Lyme disease wasn't bad enough, scientists say some ticks carry a pathogen that causes a sudden and dangerous allergy to meat. Yes, meat.

The Lone Star tick (Amblyomma americanum) mostly looks like your average tick, with a tiny head and a big fat behind, except the adult female has a Texas-shaped spot on its back—thus the name.

Unlike other American ticks, the Lone Star feeds on humans at every stage of its life cycle. Even the larvae want our blood. You can’t get Lyme disease from the Lone Star tick, but you can get something even more mysterious: the inability to safely consume a bacon cheeseburger.

"The weird thing about [this reaction] is it can occur within three to 10 or 12 hours, so patients have no idea what prompted their allergic reactions," allergist Ronald Saff, of the Florida State University College of Medicine, told Business Insider.

What prompted them was STARI, or southern tick-associated rash illness. People with STARI may develop a circular rash like the one commonly seen in Lyme disease. They may feel achy, fatigued, and fevered. And their next meal could make them very, very sick.

Saff now sees at least one patient per week with STARI and a sensitivity to galactose-alpha-1, 3-galactose—more commonly known as alpha-gal—a sugar molecule found in mammal tissue like pork, beef, and lamb. Several hours after eating, patients’ immune systems overreact to alpha-gal, with symptoms ranging from an itchy rash to throat swelling.

Even worse, the more times a person is bitten, the more likely it becomes that they will develop this dangerous allergy.

The tick’s range currently covers the southern, eastern, and south-central U.S., but even that is changing. "We expect with warming temperatures, the tick is going to slowly make its way northward and westward and cause more problems than they're already causing," Saff said. We've already seen that occur with the deer ticks that cause Lyme disease, and 2017 is projected to be an especially bad year.

There’s so much we don’t understand about alpha-gal sensitivity. Scientists don’t know why it happens, how to treat it, or if it's permanent. All they can do is advise us to be vigilant and follow basic tick-avoidance practices.

[h/t Business Insider]