Why x2?

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I think I have asked this before somewhere (long time ago). But anyway, why is the PL score the same as the number of pairings won times two? A percentage would make much more sense to me. Or just skipping the multiply with two part.

PEZ15:03, 4 December 2011

May be because of tie (exactly 50% APS) - in this case both bots get by 1 point.

Jdev15:20, 4 December 2011

Or 0.5 points without the multiplier.

PEZ19:15, 8 December 2011

I'm not sure, but i think, that it is you invented PL and you was inspired by English football Premier League. So you must understanding better rules of PL, than i, since i'm not football fan:)

Jdev19:46, 8 December 2011

Lolz. I remember that I was very supporting of the idea to measure how "undefeatable" a bot was. But I can't recall being the one to use the PL analogy. I do remember fighting fiercely for focusing on plain Average Percent Scores and not all that ELO hoochie coochie, but lost that argument back then. It feels like a glitch in the matrix when you remind me of the old PL discussions, because one of the first questions I had when "returning" to Robocode this time was "What is APS?". =)

PEZ17:38, 9 December 2011

Funny, I feel like a bunch of stuff you used to advocate for came to fruition in your absence. APS is one. Another is that we now do a pretty good job separating out gun terminology like Visit Count Stats, GuessFactors, Pattern Matching, and Play It Forward, instead of using confusing names for multi-part systems, like “GuessFactor Targeting” == VCS + Segmentation + GFs or “TronsGun” == KNN + PIF.

PS - Can you see more than 3 replies now, or still having that problem?

Voidious21:08, 9 December 2011

I have no troubles reading the full threads any longer. I like how I get notified when there are replies to threads I've engaged in. Just wish there was a Like button. =)

PEZ20:43, 10 December 2011

Or, maybe, it was Pulsar. I'm sure, that it was European, but not Englishman and i think it was Swede. I saw conversation about it somewhere in old wiki, i think

Jdev19:53, 8 December 2011

I think it's very likely Darkcanuck just copied what was done on the old RoboRumble server, and I think the soccer (er, football) reference is accurate there. I guess I would also prefer to just see wins instead of (wins * 2). Not sure I've ever seen a tie anyway...

Voidious19:56, 8 December 2011

Here's the page from the original wiki: http://old.robowiki.net/robowiki?RoboRumble/PremierLeague The description of how it works is unsigned, but from the chat I always assumed it was suggested by PEZ.

The new rumble server is a reverse-engineering effort, largely supported by what I could glean from the wiki. For the PL score, I cheated a little bit: since the odds of having a perfect 50/50 APS split is vanishingly small, I just multiplied the number of won pairings by two and skipped the calculation of ties. I'm not sure how the old rumble server's code handled it.

Changing the display to # won pairings / total pairs would be trivial. But I don't really want to add more columns, so would retiring the "classic" PL score column be ok? I also have another change in the works to add APW: average percentage win rate over all pairings, where the win rate for each pairing is # wins / # battles for that pair. That's based on the discussion from a while back about alternative scoring systems.

Darkcanuck22:10, 9 December 2011

You certainly have my vote to change it (and to add APW in the future!).

Voidious22:15, 9 December 2011

Wow, yes, that was indeed my suggestion to begin with. I remember it now. As I read the old discussion it seems that there is agreement around making it really transparent. When I originally suggested it I didn't realize just how seldom bots truly tie. I also find this

Why, if you don't win against a bot you could as well have 0 points. 3 points for a win and zero for other outcomes might be a bit weird though, so make it 1 point for the win instead. -- PEZ

Seems like what I find weird today, I found weird back then too. =)

I suggest making that change and also to remove the old PL reference. Yes, it hurts a bit, but it'll make for one less legacy thing for newcomers to wonder about.

PEZ20:38, 10 December 2011

I would also prefer counting 1 point for a win and 1/2 for a tie in PL. Other formats for showing the score could be:

- Leaving wins, ties and losses separated, like "840-0-1".
- Or using Copeland score, which is (wins - losses), 840 wins and 1 loss would be "839". The difference is, missing pairings would be more easily counted as ties instead of losses.

As for APW, after reading a lot about voting/ranking systems, I realized PL is superior to APW in the fairness subject. If there would be a new ranking system, it would vote for a Schulze based one.

MN01:42, 16 December 2011
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