(Nontopical life update: Current 18.06 homework status: 34% (mildly screwed, probably won’t finish before I leave my cozy home for the U.S. and I usually struggle to get into the mood for homework while traveling, but I guess I’ll have to)) (I’ve been spending most of my uptime doing said homework and running errands, and my downtime catching up on Last Week Tonight with John Oliver while farming the Flight Rising Coliseum. And, okay, making the above status panel. Live version here courtesy of Dropbox’s Public folder. No regrets.)
Day 3 (Excursions)
Morning routine snipped. We come to the middle school again to eat breakfast and gather; the contestants will be taking their tests here (accompanied by one bottle of “Buff” energy drink each) while the rest of us will be going on an excursion. Before this happens, though, two Taiwanese contestants ask me and Hsin-Po some math problems. There’s a geometry problem, which I fail to solve:
(paraphrased) In triangle △ABC, ∠A is 40° and ∠B is 60°. The angle bisector of ∠A meets BC at D; E is on AB such that ∠ADE is 30°. Find ∠DEC.
Hsin-Po figures out that, once you guess (ROT13) gur bgure boivbhf privna vf nyfb na natyr ovfrpgbe naq gurl vagrefrpg ng gur vapragre, lbh pna cebir vg ol pbafgehpgvat gur vapragre naq fubjvat sebz gur tvira natyr gung gurl vaqrrq pbvapvqr. Then, there’s a combinatorics problem in a book with a solution that they’re not sure about:
Shamelessly getting unfinished business out of the way. Yup, that’s me.
Excursion Day 1. We traveled down to Yilan on a bus. I played guess-it with Paul.
I was quite surprised at myself for remembering this game, but I think it’s simple and little-known enough to be worth mentioning. Guess-it is a remarkably pure game of luck and bluffing from one of Martin Gardner’s columns, played with a small odd number of cards, e.g. the 13 cards of one poker suit. The cards are dealt evenly to players (who can look at them) with one card left over, which is kept face down; players take turns choosing one of two actions:
Name a card and ask the other player if he or she has it. These questions must be answered honestly.
Guess the left-over card. The guesser wins if correct; the other player wins if not.
Guess-it is not trivial because sometimes you should ask the other player if he or she has a card that you already see in your hand; otherwise whenever you answered “no” to a query you’d immediately guess that the asked card is the hidden one. It is actually a solved game in the sense that the probabilities of the Nash equilibrium strategy for when to guess and when to bluff have been worked out already, but they’re not simple probabilities by any means and humans are terrible randomizers anyway. A few rounds of it sure beats rock-paper-scissors. I was very amused to lose almost all our games with 11 cards but win almost all of our games with 13.
Okay, no more gratuitous narrative excursions into game-theory. The first stop, National Center for Traditional Arts, was a very laid-back culture place with old-fashioned retro shops and streets.
We watched a 3D glove puppetry (布袋戲) video, in the same session as a lot of the leaders.