Coye Cheshire & Andrew Fiore June 28, 2015 // Computer-Mediated Communication Game Theory, Games, and CMC

6/28/2015Computer-Mediated Communication — Cheshire & Fiore1 Open Discussion: Marc Smith Talk

6/28/2015Computer-Mediated Communication — Cheshire & Fiore2 Single-strategy tournament

6/28/2015Computer-Mediated Communication — Cheshire & Fiore3 Multiple-strategy tournament (1)

6/28/2015Computer-Mediated Communication — Cheshire & Fiore4 Multiple-strategy tournament (2)

6/28/2015Computer-Mediated Communication — Cheshire & Fiore5 Why Game Theory for mediated communication?

6/28/2015Computer-Mediated Communication — Cheshire & Fiore6 Game Theory “Game theory is the systematic study of interdependent rational choice. It may be used to explain, to predict, and to evaluate human behavior in contexts where the outcome of action depends on what several agents choose to do and where their choices depend on what others choose to do.”

6/28/2015Computer-Mediated Communication — Cheshire & Fiore7 Game Theory and Core Concepts  Analytical vs. Behavioral Game Theory  Cooperative and Non- Cooperative Games  Zero and Non-Zero Sum Games  One-Shot vs. Repeated  Equilibria  (i.e., Nash Equilibrium) (example for cooperative game)

6/28/2015Computer-Mediated Communication — Cheshire & Fiore8 Why the Prisoner’s Dilemma? … demonstrates how communication between individuals can significantly alter “the best strategy” for solving the problem.

6/28/2015Computer-Mediated Communication — Cheshire & Fiore9 The Evolution of Cooperation  Axelrod’s famous (1984) tournament allowed individuals to submit any strategy.  All strategies played each other in the tournament.  The winner was one of the shortest submissions, about 4 lines of code.

6/28/2015Computer-Mediated Communication — Cheshire & Fiore10 The Simple Effectiveness of the Tit-for-Tat Strategy  Tit-for-Tat: begin with ‘cooperate’ and then do whatever the opponent did on the last turn.

6/28/2015Computer-Mediated Communication — Cheshire & Fiore11 Lessons from Tit-for-Tat  Be nice  It starts by cooperating. Most top- scoring strategies do this.  Be forgiving  It quickly and happily returns to cooperation without holding a grudge.  Be able to retaliate  It never allows defection to go unpunished.  Be clear  It is predictable and easy to understand. It pays to be predictable in non-zero sum games.

6/28/2015Computer-Mediated Communication — Cheshire & Fiore12 Is Tit-for-Tat Always the Answer?  2-person repeated PD  N-person PD Public Good

6/28/2015Computer-Mediated Communication — Cheshire & Fiore13

6/28/2015Computer-Mediated Communication — Cheshire & Fiore14 Some common complaints…  “Hey, isnt this rational choice?”  “This stuff explains the problem, not the solution!”  “A theoretical tool cannot explain real life, right?” (Picture courtesy vismod.media.mit.edu)

6/28/2015Computer-Mediated Communication — Cheshire & Fiore15 Revisiting our earlier question…Where does this apply to CMC? Del.ic.ious

6/28/2015Computer-Mediated Communication — Cheshire & Fiore16 Games and Game Theory Implications for Computer Games?

6/28/2015Computer-Mediated Communication — Cheshire & Fiore17 Remember…sign up for presentations