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Using competition to motivate students: an AI assignment case study
Andrew WilliamsGames Team [email protected]
Index
1. Games at Bolton2. Hexapawn assignment in AI3. The role of competition4. Future directions5. Questions
Games at Bolton
Games at Bolton Three dedicated members of staff
About a dozen others contribute 138 current students
55 first years Sixteen graduates so far
Two dedicated games labs 25 PCs each Including PlayStation NetYaroze and PS2
Linux Consoles
Games at Bolton
Two courses: Computer Games Software Development
Very technical Now in its fourth year
Games Design More creative and less technical First recruitment September 2005
Games at Bolton
Sixteen students have graduated from the CGSD course so far Four are working for a local games
company One has devised and delivered games
courses for teenagers One has set up his own company
producing educational games Several teams working on “mods”
Hexapawn Assignment in AI
Why I’m not boring (*)
Chiefly because of my chess program Started in 1998 Equal 5th in first Computer Chess
Tournament (CCT1), February 2000 15th in World Computer Chess
Championships, Maastricht 2002 8th in first CCT-BLITZ tournament,
October 2005
* According to my boss
The AI module A level 3 module
Optional All games students do introductory AI
elsewhere in their studies Offered to students from other
programmes Usually taught by two people in tandem,
each covers topics that he finds interesting I like 2 person, perfect information games
Two person, perfect information games
Chess Draughts Noughts and
Crosses Hexapawn
Hexapawn rules: White goes first Pawns move one square
forward… … or they can capture
diagonally Win if your pawn reaches the end Lose if you have no moves (or no
pawns)
Choosing hexapawn
Hexapawn is more interesting than OXO in terms of game-tree search Expand the board Change piece behaviour
Small-sided game still too easy
Thought experiments: Who wins if White starts with b1-b2? Who wins if White starts with a1-a2?
1
2
3
a b c
If I do this and he does that…
1
2
3
a b c* a1-a2 is left as an exercise
Starting with b1-b2 b1-b2 a3xb2 c1xb2 c3-c2 a1-a2 c2-c1 And we reach the position below
Black has reached White's back rank (on c1), so Black wins
A new game with new rules 8x8 board 16 pieces each Double first move
from the back rank Over four weeks
we developed a simple program in C for playing hexapawn
The “hexapawn” assignment The assignment was to improve the
program in certain ways: Better evaluation Better game-tree search
Students could swap object files to test against each other without revealing their techniques
30% awarded for performance in a tournament (20% for trying interesting things, 50% for report and documentation)
The Role of Competition
My kind of assignment
Essentially, the assignment is a miniature version of what we do in the world of computer chess Difficult Frustrating Easy to judge progress Fun Rewards thorough testing
Results The assignment has been conducted twice
with twelve students in total Average score of 60% Several students have commented
favourably on the assignment Several exchanged versions over Christmas
so that they could assess their progress One student complained that he spent so
long on hexapawn that he neglected other work
Results
A wide range of techniques were implemented Player on move is critical Null move doesn’t seem to work well
Contrast with chess, where null move is key Hash tables are a major win
Predictably hard to get working It turns out that leaving defenders back
is a very good strategy
Results All students managed to produce a
version that could beat the bog-standard williams program I had expected this
One student produced a version that consistently beat my best version I had not imagined that this could
happen! It had never occurred to me to leave
defenders back
Future Directions
Time to put hexapawn away?
The structure of courses in our department has changed
Probably from next year, only games students will study AI
Replace hexapawn with something more like a video game But retain the element of competition as
a motivating tool
Any Questions?