1 of 28

​

Game Theory

For

Blockchain

​

2 of 28

Workshop Consisting

Of Games

Learning Goals:

  • Game theory basics.
  • How this is linked to blockchain.

​

3 of 28

Workshop Consisting

Of Games

Game Goals:

  • Get tokens.
  • Non competitive.

4 of 28

Stag Hunt

  • Reveal coin to hunt the stag.
  • Reveal nothing to hunt the rabbit.

5 of 28

​

​

Pure Nash

Equilibrium

A) B)

No one regrets its strategy.

6 of 28

​

​

Mixed

Nash Equilibrium

1/2

C)

1/2

1/2

1/2

(1/2) *( )

7 of 28

​

​

Prisoner

Dilemma

Buyer\Seller

Cooperate

Defect

Cooperate

(+1,+1)

(-1,+2)

Defect

(+2,-1)

(0,0)

Unknown number of repetitions

8 of 28

​

​

Prisoner

Dilemma

Buyer\Seller

Cooperate

Defect

Cooperate

(+1,+1)

(-1,+2)

Defect

(+2,-1)

(0,0)

3 remaining

9 of 28

​

​

Prisoner

Dilemma

Buyer\Seller

Cooperate

Defect

Cooperate

(+1,+1)

(-1,+2)

Defect

(+2,-1)

(0,0)

2 remaining

10 of 28

​

​

Prisoner

Dilemma

Buyer\Seller

Cooperate

Defect

Cooperate

(+1,+1)

(-1,+2)

Defect

(+2,-1)

(0,0)

1 remaining

11 of 28

​

​

Prisoner

Dilemma

Buyer\Seller

Cooperate

Defect

Cooperate

(+1,+1)

(-1,+2)

Defect

(+2,-1)

(0,0)

Switch party next round

12 of 28

​

​

Zero Sum

Games:

Equal / Not Equal

Tiger\Monkey

Tree

(put coin)

Cave

Tree

(put coin)

(+1,-1)

(0,0)

Cave

(0,0)

(+1,-1)

13 of 28

​

​

Zero Sum

Games:

Equal / Not Equal

Use mixed strategy (play at random).

Tiger\Monkey

Tree

(put coin)

Cave

Tree

(put coin)

(+1,-1)

(0,0)

Cave

(0,0)

(+1,-1)

14 of 28

​

​

Minimum

acceptance

  • User chooses how much he offers.
  • Miner chooses his minimum accepted.

15 of 28

​

​

Transaction

Fees

  • User chooses how much he offers.

THEN

  • Miner chooses if he accepts or not.

16 of 28

​

​

TX Fees With

Full Blocks

  • Users chooses how much he offers.

THEN

  • Miner chooses to accept up to two of them.

17 of 28

Schelling Point

  • Choose a color
  • If your color is the most chosen one, you get 1 coin.

18 of 28

Schelling Coin

  • You get 4 coins if your color is chosen by the mechanism.

19 of 28

  • Answer the question by putting a token of the corresponding color:
    • What color is this slide?
  • If your color is the most chosen one, you get 1 coin.

Schelling Coin

20 of 28

  • You get 20 coins if your color is chosen by the mechanism.

Schelling Coin

21 of 28

  • Answer the question by putting a token of the corresponding color:
    • What color is this slide?
  • If your color is the most chosen one, you get 1 coin.
  • You may accept bribes!

Schelling Coin

22 of 28

Mechanism

Design

  • You have one object.
  • Parties have different valuations to it.
  • They can submit bids.
  • You decides of the rules in order to get the most of your object.

23 of 28

Mechanism

Design

  • Pick a coin of the color of your choice and hide it into your pocket but don’t show it.

24 of 28

Mechanism

Design

  • Valuations are
    • Blue: 6
    • Red: 2
    • Green: 3
  • Place your bid put putting the corresponding amount in your hand.

25 of 28

​

​

Pirate

​

26 of 28

​

​

Hawk

Dove

27 of 28

Thanks!

I am Clément Lesaege�@clesaege

Co-founder of Kleros.io

​

You can reach me at:

clement@kleros.io

​

28 of 28

Attribution

Illustrated normal form matrix by Christopher X Jon Jensen (CXJJensen) & Greg Riestenberg under creative common license.

​

​