Fun interactive game theory simulator shows how trust and mistrust evolve

This simulation, called The Evolution of Trust starts with a variation of the prisoners' dilemma. You can choose to put a coin into a slot. Another person has the same choice on a different machine. You can't communicate with the other person. The only thing you know is this: if the other person put a coin in their slot, you will receive 3 coins. And if you put a coin in your slot, the other person will get 3 coins. What's the best strategy?

Case 1: other person inserts coin. If you put a coin in the slot, you will have a net gain of 2 coins. If you don't put a coin in the slot you will gain 3 coins. So the best thing to do is not put a coin in the slot.

Case 2: other person doesn't insert coin. If you put a coin in the slot, you will have a net loss of 1 coin. If you don't put a coin in the slot you lose nothing. So the best thing to do is not put a coin in the slot.

In either case, it's to your advantage not to put a coin in the slot. But what happens when you play several rounds of the game with the same person? Are there better strategies? Yes, and this excellent interactive simulation by Nicky Case walks you through them in an entertaining way. Read the rest

Game theory: pedestrians versus autonomous vehicles

Any well-designed self-driving car will be at pains to avoid killing people, if only to prevent paperwork delays when they mow someone down. Read the rest

Google: Chrome will no longer trust Symantec certificates, 30% of the web will need to switch Certificate Authorities

In 2012, Google rolled out Certificate Transparency, a clever system to spot corrupt "Certificate Authorities," the entities who hand out the cryptographic certificates that secure the web. If Certificate Authorities fail to do their jobs, they put the entire electronic realm in danger -- bad certificates could allow anything from eavesdropping on financial transactions to spoofing industrial control systems into accepting malicious software updates. Read the rest

A "travel mode" for social media - after all, you don't take all your other stuff with you on the road

As the US government ramps up its insistence that visitors (and US citizens) unlock their devices and provide their social media accounts, the solution have run the gamut from extreme technological caution, abandoning mobile devices while traveling, or asking the government to rethink its policy. But Maciej Cegłowski has another solution: a "travel mode" for our social media accounts. Read the rest

UK cops beat phone encryption by "mugging" suspect after he unlocked his phone

Detectives from Scotland Yard's cybercrime unit decided the easiest way to get around their suspect's careful use of full-disk encryption and strong passphrases on his Iphone was to trail him until he made a call, then "mug" him by snatching his phone and then tasking an officer to continuously swipe at the screen to keep it from going to sleep, which would reactivate the disk encryption. Read the rest

Youtube's new "offline first" product for India treats telcos as damage and routes around them

Yesterday, Google announced "Youtube Go," an "offline first" version of the popular video service designed for the Indian market where internet coverage is intermittent, provided by monopolistic carriers that have a history of network discrimination, and where people have a wide variety of devices, including very low-powered ones. Read the rest

A catalog of weird-ass corners of game theory research

Game theory is the place where politics, economics, psychology and math meet, and it offers the seductive promise of being able to quantify empirically optimal outcomes from thorny problems ranging from whether to go to war to how to split the tab at a restaurant. Read the rest

Supreme Court ruling is a blow to copyright trolling business-model

In 2013, the Supreme Court heard Kirtsaeng, a copyright case brought by the publisher Wiley, who argued that legal books became illegal when brought into America, because their copyright licenses were nation-specific. Read the rest

Using distributed code-signatures to make it much harder to order secret backdoors

Cothority is a new software project that uses "multi-party cryptographic signatures" to make it infinitely harder for governments to order companies to ship secret, targeted backdoors to their products as innocuous-looking software updates. Read the rest

Chimps beat humans at game theory

In Chimpanzee choice rates in competitive games match equilibrium game theory predictions, a paper in Nature by Colin Camerer and colleagues, researchers document the astounding performance of chimpanzees in classic game-theory experiments -- a performance that's substantially superior to humans who play the same games: Read the rest

On anachronism in literary analysis

Jane Austen was not a game theorist. Read the rest

Strategies for the future: accuracy vs. resilience vs. denial

Seth Godin's daily thoughts are always provocative and thoughtful, but today's is a particularly timely and apt one for the new year. Godin describes three ways of coping with the future: Accuracy (correctly guessing what will happen); Resilience (admitting you can't make accurate predictions, so preparing to weather a variety of storms); and "Denial" (pretending nothing will change and getting clobbered as a result). I'm shooting for "Resilient" myself, but if I'm brutally honest, I have to admit that I have moments where I assume that I can be Accurate and where I'm too tired to do anything except Deny. Read the rest

Betrayers' Banquet: gourmet dining vs the Prisoner's Dilemma

Ed writes, "The Betrayers' Banquet is an experimental dining experience from London, where guests play the iterated prisoner's dilemma to win a better or worse meal. Each of the 48 participants is served eight different courses over two hours; two starters, four mains and two desserts. While all dishes are edible, their allure differs considerably between the top and the bottom of the table; those at the top will enjoy a fine dining experience to match any in London, while those at the bottom will grapple with pickled walnuts, chicken's feet soup, lumpy gruel, and worse." Read the rest

Twitter party game/Prisoners' Dilemma: "I Eat Poo"

Jeremy Bornstein proposes a party game/Prisoners' Dilemma variant called "I Eat Poo," in which the players pass their phones to their left and invite the player there to type (but not send) an embarrassing message into their own Twitter account. Phones are handed back and each player gets to decide whether to allow the message to be posted, or to forfeit $20 to the message-writer; the phones are handed back to the message-writer, and the hand-over may also include a covert $20 payoff. The climax comes when the final accounting is made: if everyone has paid $20, or no one has paid $20, then nothing happens (the messages aren't posted). Otherwise, the paid-up don't get posted, the unpaid do, and the pot is split among the message-writers. Read the rest

What happens when actual prisoners play The Prisoner's Dilemma?


The Prisoner's Dilemma is a basic part of game theory. Two prisoners are given the choice between informing on the other, or staying silent. They can't communicate with each other. The choices they make determine how many years in prison they both get.

This analogy/brain game is often used to demonstrate the ways that different people can work with or against each other in economic and social situations. Now, for the first time, scientists have done a study based on The Prisoner's Dilemma that used real prisoners. Instead of time off their sentences, they were given the choice of competing or cooperating to earn goodies like coffee and cigarettes.

And here's the surprise: Compared to college students, the prisoners actually cooperated with each other much more often. Read the rest

Tic-Tac-Toe squared

Want to play a game of Tic-Tac-Toe that's genuinely challenging and hard? Try "Ultimate Tic-Tac-Toe," in which each square is made up of another, smaller Tic-Tac-Toe board, and to win the square you have to win its mini-game. Ben Orlin says he discovered the game on a mathematicians' picnic, and he explains a wrinkle on the rules:

You don’t get to pick which of the nine boards to play on. That’s determined by your opponent’s previous move. Whichever square he picks, that’s the board you must play in next. (And whichever square you pick will determine which board he plays on next.)...

This lends the game a strategic element. You can’t just focus on the little board. You’ve got to consider where your move will send your opponent, and where his next move will send you, and so on.

The resulting scenarios look bizarre. Players seem to move randomly, missing easy two- and three-in-a-rows. But there’s a method to the madness – they’re thinking ahead to future moves, wary of setting up their opponent on prime real estate. It is, in short, vastly more interesting than regular tic-tac-toe.

Ultimate Tic-Tac-Toe (via Kottke) Read the rest

Stag Hunts: fascinating and useful game theory model for collective action problems

Yesterday, I wrote about some Johns Hopkins students who overcame a game theory problem and got an A for the whole class. I called it a non-iterated Prisoner's Dilemma, but as Tim Harford points out, it's more of a Stag Hunt, a game theory category that I hadn't been aware of, and which has fascinating implications for lots of domains, including Internet peering:

In the stag hunt, two hunters must each decide whether to hunt the stag together or hunt rabbits alone. Half a stag is better than a brace of rabbits, but the stag will only be brought down with a combined effort. Rabbits, on the other hand, can be hunted by an individual without any trouble.

There are two rational outcomes to the stag hunt: either both hunters hunt the stag as a team, or each hunts rabbits by himself. Each would prefer to co-operate in hunting the stag, but if the other player’s motives or actions are uncertain, the rabbit hunt is a risk-free alternative.

Right on queue

(Image: [ C ] Lucas Cranach - Stag Hunt of the Elector John Frederick, a Creative Commons Attribution (2.0) image from centralasian's photostream) Read the rest

More posts