1. Emily Short and Richard Evans – Little Text People
Cotillion
Emily Short and Richard Evans
– Little Text People

2. Cotillion Project Interactive comedy of manners
Set in the world of Austen

3. Gameplay Model social practices
Allow players to experiment with appropriate and inappropriate behavior
Sims-like freedom within a narrative structure

5. Interaction Features
Real-time
Multiplayer
PC / NPC Agnostic

6. Conversation Model Challenges: Anyone can speak at any time
Any character can be an NPC
Character knowledge and attitude can change
Content generation needs to be manageable
Many standard models of conversation (including past work of mine where the player is talking to

7. Information Structure
Beliefs and Questions
Emotional Responses
Membership Categorization
Turn-taking

8. Beliefs Propositions about the world
Discovered through conversation or world model
Similar to “facts” in previous talks except that there’s an explicit tracking of predicate and participant objects, and it’s possible for a character to hold a belief that is in fact wrong

9. Default way of saying a particular belief
Character-specific overrides
Can include standard responses for if the listener accepts or rejects the statement

10. Questions Template for information the character wants to have
Can only be asked if another character present has a belief that fits the template

11. Generated by conversation and contact with the world model
Aid to conversation continuity and transitions between topics

12. Here’s what you would get from a standard dialogue tree…

13. Here’s the structure if we just have beliefs and questions: sooner or later you will run out of content no matter how much you make

14. Emotional Responses Beliefs are also tagged with emotional effects
Expressing a negative belief about someone could lead to them feeling insulted
Mentioning that you’re very rich could lead to someone…
envying you
thinking you’re bragging
deciding you’d be a good marriage prospect

15. Emotional Reaction Library
Large library of possible reactions
Layers of specificity
“being a host reacting to someone insulting the wine you served”
“responding to someone insulting your friend in your presence”
“responding to someone being unpleasant”

16. However, emotional reactions are also always available to both characters…

17. And of course we have a large number of possible emotional reactions available

18. Here’s an example of this in practice: [give background of scene quickly]. Question / responding belief / response to that belief / emotional reaction.

19. Fine-Grained Characterization
Miss Bates
Mr Collins
Talks constantly
Likes to talk about her niece
Likes to give advice
Name-dropper, always mentioning rich patroness

20. Fine-Grained Characterization
Miss Bates
Mr Collins
Talks constantly
Positively score spoken beliefs
Likes to talk about her niece
Positively score beliefs on the topic of her niece
Likes to give advice
Positively score beliefs that are tagged as “correcting”
Name-dropper
Positively score actions that result in characters having questions about his patroness

21. Interface of Information & Emotion
Informational content tied to narrative context
Emotional content tied to relationship between characters
Emotional content generates dramatic payoffs

22. Smalltalk

23. Smalltalk

24. Smalltalk

25. Other types of scene…

26. Other types of scene…

27. Other types of scene…

28. Other types of scene…

29. Other types of scene…

30. Harvey Sacks on Conversation
Membership Categorization Devices
Turn-Taking
Tying structure
Pre-sequences
Preferred sequences
One of the inspirations for our conversation model was Harvey Sacks’ work on conversation analysis.
Today I’m only going to talk about two aspects: Membership Categorization Devices and Turn-Taking

31. Membership Categorization Devices
A character is playing many roles at once
Sacks starts with the familiar observation that a character can be in many practices at once.
In each practice he has a role.
He is evaluated with respect to the many various roles he plays.

32. Many roles at once: Mr Darcy
A member of the gentry
A friend of Bingley
A brother to Georgiana
A participant at the ball

33. Membership Categorization Devices
A character is playing many roles at once
For each role, we can ask: is he good at performing that role?
A character is in many practices at once.
In each practice he has a role.
He is evaluated with respect to the many various roles he plays.

34. Is he good at performing these roles?
A member of the gentry: noble
A friend of Bingley: loyal
A brother to Georgiana: kind
A participant at the ball: aloof

36. Choosing How to Evaluate
Miss Bates’ sycophantic remark…
Polite
Low-breeding
(Ignore)
Individual personality determines autonomous choice
The reason Mr Quinn preferred the negative interpretations of Miss Bates’ remark was that he wanted to see her in a bad light. I will come back to this.

37. Multiple Roles Breeding Constitution Propriety Accomplishments Spouse
Intelligence
Politeness
Attraction
Sensibility …
In Cotillion, we model tons of different role evaluations:

38. Compare with Other Games

39. Role Evaluation
Agents can remember justifications for their role evaluations
Agents can communicate role evaluations to others
Role evaluations can affect subsequent autonomous behavior
But its not how many role-evaluations we model – its what the agents do with them that matters.

40. Communicating Role Evaluations
Example: I was playing the murder mystery scenario. One of the characters had been shot and the doctor was examining the body. Afterwards, the doctor kept giving me funny looks, sniffing at me dismissively. I didn’t understand why – I had never been mean to him. But after some debugging, I found out the reason. Earlier on, I had been rude to the butler. The butler had then left and gone to the kitchen, where he had had a conversation with the doctor, where he had explained to the doctor about my rudeness. The doctor had taken his opinion on board.

41. Turn-Taking
If the last utterance has selected a next-speaker, that speaker should speak next
Otherwise, the floor is open
Otherwise, the floor is open. It’s a free-for-all. But once somebody has started speaking next, he becomes the next speaker, and everyone else should remain silent.

42. Tom has seen a ghost and even though it is not his turn to talk, he cannot help himself. He blurts out his fear.

43. Planning with Conditional Effects
So our game is agnostic between human players and computer players. How do we get the NPCs to behave properly? How do they work out what to do?

44. Planning
In most planning systems, the agent’s estimation of the consequences of the action is much simpler than the actual consequences of the action

45. Going to the Toilet Execution: Planning: route into bathroom
if nobody else around
play animation
satisfy Bladder motive
Planning:

46. Going to the Toilet

47. Problems It is error-prone It misses conditional-effects
Strips, The Sims, bothuse this approach

48. Planning with Conditional Effects
Our planner uses the actual future world state – not an approximation
We return to the previous world-state by UNDOing the postconditions
We can do this because we are working in a custom DSL which supports UNDO
(Imagine trying to add UNDO to arbitrary C++ code)

50. Conditional-Effects Planning
In this architecture, getting the agents to play games well doesn’t mean programming algorithms.
It just means telling the agents what emotional states they will be in when certain conditions hold.

51. Planning with Conditional Effects
Real people don’t play a game in a vacuum.
They play the game with others. Other people with whom they have various complex relationships.
Those relationships affect the way they play. A move in a game isn’t just a move in a game – it can also be a trouncing of your enemy, or a betrayal of your friend.

53. Planning with Conditional Effects
This is what it is to care about someone: to get upset when they get upset.