An addition/subtraction game
The numbers 1, 2, 3, and 4 are written on a board. Alice writes a "+" or "-" sign in front of one of the numbers, and then Bob and Alice take turns. Once the four signs are written, the arithmetic expression is then evaluated. Bob gets points equal to the absolute ...

Video: safety in numbers
Consider the following game. Two generals have 5 units each to deploy. Each person decides how many units to send to battle. The general who sends more troops will win, but it's a draw if they both send the same number. Each also has the option of "passing" which averts war and ...

The wallet game: a neat auction
Imagine you are taking a game theory class, and the professor announces an experiment. You and another student are called up to the front of the classroom to participate in an auction. Here is how the auction works: --the prize money equals the sum of money in both of your wallets --the winner is ...

How to beat the Prisoner’s Dilemma in the TV game show Golden Balls
Golden Balls is an amusing British game show. Especially interesting is the final contest which is a version of the Prisoner's Dilemma. If you're never seen the show, here is how it works. Each of two contestants independently chooses to split or steal the final prize. If both choose split, then ...

A location game on a triangle
A father bequeaths a triangular piece of land to his children, Alice and Bob. The father was known to be quirky, and in his will, he specified a rather unusual way for the land to be divided. On a map of the land, Bob is to mark a location of his choosing. ...

A game of Guts
Imagine a casino offers a new game called "Guts." A dealer wants to test the game, so he recruits two strangers (Alice and Bob) for an experiment. The game works as follows. Alice will secretly write an even integer on a piece of paper, and Bob will secretly write an odd ...

The supply game
(Apologies my site has been down today with technical issues. I am looking to get it resolved) Recently India caused a stir in global markets when it banned its cotton exports. The ban was a result of the unstable cotton global market, which has lead China to stockpile its cotton supply ...

Number matching game
This is a game I created after reading about a similar card game in Game Theory: a Very Short Introduction. It's a simple example of a zero sum game that's slightly more complicated than rock-paper-scissors. Here is the game: Alice and Bob play a number matching game. Each simultaneously picks an integer ...

What’s the probability of a pure strategy Nash equilibrium?
This is a problem I adapted from the free e-book Algorithmic Game Theory. I had some fun solving it, and so I wanted to share it.

Video: understanding the Shapley-Shubik voting power index
With the election coming up this year, I thought it timely to revisit some voting theory. One of the useful concepts in voting theory is having an index that determines how powerful particular voters are. One of the voting power indices used is called the Shapley-Shubik index, which I have talked ...

The card game le her
While game theory as we know it began about 60 years ago, there were game theory ideas dating back to hundreds and thousands of years ago (see how game theory solved a religious mystery). Another early example happened in 1713, when James Waldegrave provided a mixed strategy solution to a two-person ...

How not knowing game theory can cost you millions
A few months ago, The Economist ran a great article about some of the practical applications of game theory. My favorite part of the article was the following paragraph which highlights how ignorance of game theory can be costly:

Video: how to buy a car using game theory
This video is about a car buying technique from Professor Bruce Bueno de Mesquita. I previously enjoyed one of his TED talks about predicting political events. The video is short and offers great practical advice for buying a car in America. Give it a watch:

Amazon’s $23.6 million book: a hilarious bidding war
Nearly 1 year ago, an out of print book about flies was listed at over $23.6 million on Amazon.com. As good as Peter Lawrence’s The Making of a Fly was, no one could see the sanity in that price. (thanks Robert for sending me the story) The listing was noticed by ...

Video: Tom Haverford uses game theory in relationship advice
Tom Haverford has a lot of funny ideas on the show Parks and Recreation. In one scene, he dispenses relationship advice to his friend about how to handle his anger. It turns out Tom has something of a hidden agenda, as the following clip illustrates.