Comments on: The Contest is Underway

By: Alan Chalker

Alan Chalker — Wed, 09 May 2007 21:21:33 +0000

I just tried the updated grade.m and it doesn’t seem to be fixed. You did this:
Old:
f = moves(i,[1 2]);
t = moves(i,[3 4]);

New:
t = moves(i,[3 4]);
f = moves(i,[1 2]);

The correct New (based upon the newsgroup discussion) should be:
f = moves(i,[2 1]);
t = moves(i,[4 3]);

Alternatively, you should update the rules to indicate the reversed order.

By: Matthew

Matthew — Wed, 09 May 2007 20:43:37 +0000

Thanks Alan. We’ve posted an update and announced it on the newsgroup.

By: Alan Chalker

Alan Chalker — Wed, 09 May 2007 19:11:39 +0000

I’m posting this both here and in the newsgroup to ensure the contest team sees it:

There is an error in the grade function, but I haven’t been able to figure it out yet.

Try to run the examples in the rules like this:

grade([7 0 2 0; 0 0 8 0; 0 7 0 0; 0 0 3 4], [1,3,3,3])
result = 31
according to the rules it should be 25

likewise

grade([7 0 2 0; 0 0 8 0; 0 7 0 0; 0 0 3 4],[4,4,4,2;4,2,2,2;2,2,2,4]);
result = 35
according to the rules it should be 17

I only discovered this because as I was testing things that should work out, my score was going up, not down.

By: Heinrich Acker

Heinrich Acker — Wed, 09 May 2007 18:05:17 +0000

There are a couple of nice new ideas in this contest! I really like the problem. What you have written aubout group intelligence and the white flag is clever, no real gentleman can welch you after this. The complexity-depended score is also interesting, although it should always be possible to avoid a penalty by using lots of functions. Let’s see what happens.

Last not least: The GUI provided with the testsuite is the best so far. It will allow spectators like me to follow the evolution of solutions in this contest.

By: Matthew

Matthew — Wed, 09 May 2007 16:46:03 +0000

Hi Alan and welcome back.

Your comment about enforcement is mostly true. We have a couple of steps we can take if someone is being difficult, but they’re fairly limited.

We’re mostly counting on our participants to cooperate. In the past, people submitting entries like these have been white hat hackers like yourself. It was all in good fun and we haven’t seen evidence of real malice. Hopefully this spirit will continue in this contest under the new rules.

If anyone notices something shady going on, please let us know right away at contest@mathworks.com.

By: Alan Chalker

Alan Chalker — Wed, 09 May 2007 16:24:28 +0000

I’m glad to see the rules changes you’ve made, which should definitely make the contest experience much better. However, I think this begs the question as to how you intend to enforce them. There still isn’t any type of authentication mechanism on the entry submission page, which means that somebody who wants to still welch the contest or spam-tweak or probe out the test suite could do it anonomously.