terminal games theoretical subtitle. a simple game 1: a>b>c 2: b>c>a 3: c>a>c

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Terminal Games Theoretical Subtitle

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Page 1: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

Terminal Games

Theoretical Subtitle

Page 2: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

A Simple Game

1: A>B>C2: B>C>A3: C>A>C

Page 3: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

Backwards Induction

1: A>B>C2: B>C>A3: C>A>C

Page 4: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

Backwards Induction

1: A>B>C2: B>C>A3: C>A>C

Page 5: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

Backwards Induction

1: A>B>C2: B>C>A3: C>A>C

Page 6: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

This doesn’t work so well if we have a cycle.

Page 7: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

Cyclical Game

Page 8: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

3’s Turn: 3 prefers a4

Page 9: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

7’s Turn: 7 prefers a1

Page 10: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

And so on… After 14 moves we return to our original state.

Page 11: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

However, an equilibrium does exist.

Page 12: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

General Idea

• By choosing the optimum shortest path through a strongly connected component and directing all other nodes inwards we can extend backwards induction through the cycles.

Page 13: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

The ‘Optimum Path’

• The Optimum Path is such that the player controlling final node in the cycle chooses its preferred destination.

• This player has no incentive to alter the path – maintaining Nash Equilibrium.

• We will use limited backwards induction to find the Optimum Path.

Page 14: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

The ‘Shortest Path’

• The Shortest Path ensures that no player controls enough nodes to change the route through the component.

• Any change by a member of the path will loop back to the path, creating a cycle.

• No player on the path will change, resulting in Nash Equilibrium.

Page 15: Terminal Games Theoretical Subtitle. A Simple Game 1: A>B>C 2: B>C>A 3: C>A>C

Hopefully the two projects are connected.

Have a good day.

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