Rock Paper Scissors and variants

Rock Paper Scissors is a game where two players simultaneously pick one of the three things in the title. Rock beats Scissors, Scissors beats Paper, Paper beats Rock, and if both players pick the same thing they tie.  Rock Paper Scissors is important in game theory, because it is a toy model that helps understand a much broader class of games.

To understand the correct strategy in Rock Paper Scissors, we must understand the difference between pure strategies and mixed strategies. A pure strategy is deterministic, where a mixed strategy is random. There are only three possible pure strategies: pick Rock, pick Paper, and pick Scissors. There are infinitely many mixed strategies available, for example assigning 50% probability to Rock, 25% to Paper, and 25% to Scissors.

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Origami: Drawer box

Drawer box

Drawer Box, designed by Akiko Yamanashi

I got this drawer box from something called the Practical Origami Convention.  I didn’t actually attend the convention, but happened to access the models later, and picked this one out to fold.  I have to imagine that there are a bunch of origamists making “practical” designs like tiny chairs to sit on, and tiny tables to hold tiny flowers.  (I’m joking, I know that practical origami has a lot of emphasis on boxes and envelopes.)

I can’t remember how many sheets this needed, but it was over 10.  Each drawer is a separate sheet, with another sheet to be used as lining.  The cabinet box (I had to look up what this part of the drawer is called) is made of 4 pieces, or maybe more?

Now obviously there’s a lot of origami that stretches what you would think is possible with a single sheet.  But other designs are more sheet-maximalist, with multiple distinct units working together.  There’s some complexity in that; you need to make the sizes match, accounting for the thickness of the paper, and some units need to be firmly attached to each other.