Information / Cybernetics

1. Information /Cybernetics Robin Burke GAM 224 Winter 2006

2. Outline • Admin • "Rules" paper • Systems of information • Cybernetics • Feedback loops

3. Admin • Draft design due Wednesday • 2nd Reaction paper due Wednesday • Presentations • Get the slides to me by Sunday, 22nd • Presentations, Monday, 23rd • Assassin game • off-line multi-player game • you can play this and write about it for one of your reaction papers • rules will be available Wednesday

4. Rules paper • Due 1/30 • Analysis paper #1: "Rules" • You should be playing your game and taking notes • Note • you cannot use lab machines to do word processing • laptops are OK

5. Important points • Thesis • "great game" is not a thesis • This is a thesis • "Inertial navigation, fixed firing direction and accurate collision detection in Asteroids create an environment in which ship orientation is highly coupled, generating emergent forms of gameplay." • No thesis = paper will not be graded • Documentation • game itself, book, lectures • other sources if used • Missing or inadequate documentation = paper will not be graded

6. How to Footnote • Little number at the end • Citation at bottom of the page NOT • At the end • Not a list of references • Not inside the text Follow the guidelines!

7. Rules paper 2 • Schemas • Emergence • Uncertainty • Information Theory • Information Systems • Cybernetics • Game Theory • Conflict • Do not use more than one • Some (most) of these we won't cover in detail in class

8. Rules paper 3 • Outlines • suggestions • Focus • do not catalog every rule, every game object • identify those items that contribute to your argument • depth over breadth

9. Rules paper 4 • Turn in • hardcopy in class 1/30 • Turn in to turnitin.com • on 1/30 • Late policy • ½ grade per day • up to 3 days late • submit only to turnitin • no need for hardcopy if it is late

10. Turnitin.com • Class id • 1432399 • Password • psychonaut

11. Information in Games • Many games require that players manipulate information • Card games • dealt card unknown • Computer games • map / location of opponents unknown • Players typically acquire discover information through play • Cards held • Map locations

12. Systems of information • Incomplete information makes for interesting gameplay • why playing cards have a front and back • Types of information • public • known to all • private • known to one player • hidden • not known by any

13. Example game • Crazy Eights • deal 8 cards • turn up top card of stock • Each player • must follow suit or rank • or draw from pile • First one out of cards wins • Special cards • 8 changes suit • A changes direction • 2 = draw 2

14. Information? • Public • Private • Hidden

15. Information economy • Games of information often have an "information economy" • a system through which • hidden information is revealed • private information becomes public • Like all economies • based on exchange

16. Example 1 • Crazy Eights • I don't know what cards my opponent holds • If she changes suit to Diamonds • private information is revealed • I'm pretty sure she has diamonds • but she is closer to winning • Tradeoff • benefit = knowledge of cards held • cost = improved opponent position

17. Example 2 • First-person shooter • I don't know what opponents are in the next room • or what the layout is • If I walk in • I'll learn what the opponents are • but I might get killed • Tradeoff • benefit = tactical knowledge • cost = risk of defeat

18. Information as reward • Often information is a reward • (more about rewards in "Play" unit) • If you are successful in some action • the game reveals more information • If you take some extra effort to explore the environment • Could be • what to do next • the location of something valuable • a map • etc.

19. Example

20. Information seeking • Players will take action to gain information • reduce uncertainty • enable preparation / planning • Meaningful choices arise • when there are multiple ways to learn • when those choices have different costs / consequences • when those choices yield different kinds or qualities of information

21. Information revealing • (Especially in multi-player games) • Players may need to keep certain information hidden • gain advantage over opponents • Meaningful choices arise • when exercising an option that might disclose valuable information • in the possibility of deception

22. Example • Civilization • players have the option of trading maps • this gives you information about opponents situation • but also reveals your assets and weaknesses

23. Game Design Issues • What kinds of information are inherent in the design? • What is the status of the information during the game? • How is information communicated? • How is hidden information revealed? • What are the costs of information? • What meaningful choices revolve around

24. Information Flow • Systems have objects that interact • Information is a quantity that objects in a system may exchange • Weiner developed cybernetics to explain this type of system • Cybernetics is an attempt to unify the study of engineered and natural systems

25. Cybernetic Systems • Cybernetics is about control • How is the behavior of a system controlled? • Control implies that there are parameters that should be maintained • Example: temperature • human body • car engine • Control implies information • Temperature messages • "too high" • "too low" • "OK"

26. Feedback Loops • Basic loop • A cybernetic system needs a sensor that detects its state • The information detected by the sensor is then compared against the desired value • If the value is not correct, the system adjusts its state • the sensor detects this new state, etc. • The system maintains stability by • feeding the information about its state back to the process producing the state

27. Two Types of Feedback Loops • Negative Feedback Loop • "inhibition" • As the state changes, the loop acts to move it in the direction of its previous state • Example • thermostat • Positive Feedback Loop • "excitation" • As the state changes, the loop acts to move it in the direction that it is moving • Example • automobile turbocharger • home team advantage

28. Audio example

29. Feedback Loops in Games • From book game state scoring function game mechanical bias controller

30. Example • game state • state of a fighting game • scoring function • player's health • controller • near-KO • bias • increase chance of critical (high damage) hit on opponent

31. Effects?

32. Example 2 • game state • state of the chessboard • scoring function • the number of pieces taken • controller • for each piece taken • bias • add a pawn to the taker's side in any position • Japanese Chu-Shogi has a rule like this

33. Effects?

34. Examples

35. Multiple Loops • Games may have multiple feedback loops in operation • Examples • racing game • a player who falls behind may be better power-ups • AI racers may adjust their ability to keep pace with player • RPG • killing monsters gives experience points for gaining levels • as a player gains levels, they gain better weapons and greater abilities • more success at killing monsters, etc. • but • game is designed so advanced areas have tougher monsters • levels get farther and farther apart

36. In General • Negative feedback loops • increases system stability • makes the game last longer • magnifies late successes • Positive feedback loops • destabilizes the system • makes the game shorter • magnifies early success • Positive feedback is usually essential • propels a player to victory • otherwise, game can go on forever • one reason that three-player games are difficult to design

37. The Other Sense • We also use the word "feedback" to mean • praise vs criticism • "I got some negative feedback on the proposal, so I'm revising it." • This is not the same • psychological sense of feedback • information about the quality of something • good or bad • cybernetic sense of feedback • a dynamic established by a system's structure that pushes its state in one direction or another • in response to information

38. Game Design Issues • Know what feedback is going on in your system • analyze how game mechanisms combine to produce feedback • Feedback may be undesirable • negative feedback may make a successful player feel punished • positive feedback may magnify ability differences between players • Not too late to think about this in your design project

39. Wednesdasy • Design project draft due • Reaction paper #2 • Read: Chapter 20