Using competition to motivate students: an AI assignment case study Andrew Williams Games Team Leader

Index 1.Games at Bolton 2.Hexapawn assignment in AI 3.The role of competition 4.Future directions 5.Questions

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 Im not boring (*) Chiefly because of my chess program Started in 1998 Equal 5 th in first Computer Chess Tournament (CCT1), February th in World Computer Chess Championships, Maastricht th 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 ? abc

If I do this and he does that… abc * 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 doesnt 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?