The new ELO-based ranking system

[MrRoboto]

@pacifiersboard said in Proposal for a new, ELO-based, ranking system:

thx! I meant a copy of the ELO file that is enabling some (local) experimentation

You can create your own copy.

File -> Make a copy

[Stucifer]

@gamerman01 They aren’t irrelevant, but they do factor in less over time generally speaking. They are important because it tries to calibrate you to your appropriate rating quickly, then from there it is more of a maintenance process unless there is relative improvement.

At the extremes of the ELO Rating, even current games are worth little unless there is an upset. If a 1900 plays 1100 and wins they will not go up very many points, as it is expected. But if the 1900 loses the 1100 will receive a huge boost and the 1900 will fall quite significantly. This does reduce the incentive for the highest-ranked players to play the lowest-ranked players, but that was already the case.

I am not sure how, but think it would be awesome if we could implement a possible Bid allowance into drastically different ELO games. Say a 500+ rating difference could get double the usual bid but have the game be worth half the points. This might promote playing between the extremes in skill levels, if useful.

[MrRoboto]

@mr_stucifer has summarized it perfectly. You clearly understand some math!

I agree, the incentive is not very high to play a lower-skilled player. However, you WILL gain points, if you win. You just need to be ready to take that risk.

Remember, I can always change how huge the impact of an upset is, by lowering or increasing the F-Factor. Right now it is at 500, which means that the system expects a player with 500 more rating than another player to win in 90% of the cases.

A lower F-Factor would squeeze everyone closer together so the difference between #1 and the last player is lower. The number of points lost when the worst player wins against the #1 still remains the same however. So the gained/lost points relative to the total amount is a higher%
So upsets hurt the better player more and will help the worse player more.

On the contrary, a higher F-Factor would increase the extreme ELO-Ratings at the top and bottom so the points lost/gained have not as big of an impact.

With the current F-Factor of 500, the difference between first and last player in BM4-rankings is 966 points. So the system expects then #1 player to win in 98,8% of games against the last one. Which sounds about right if you ask me.
Play this matchup 100 times and #1 will gain exactly 1 point 99 times and lose 79 points once.
The expected outcome is still positive for the better player…

[MrRoboto]

The system becomes stable with more games played, but still flexible enough to allow for adjustments when a player improves.

If your skill stays the same, you will oscillate around your “correct” ELO-Rating, gaining some points, losing some but always hover within a certain corridor around your skill level.

Your chance of breaking out of that corridor is when you actually improve your skill.

This is different than PPG, which becomes a lot more stable with many games.

If you play 50 games and you have, for example, a PPG of 4, that means you have 200 points.
Even a win against the best player around would increase that total to 208 points, but your PPG increases only to 4.08.

With the new system it doesn’t matter if you play 30, 50 or 100 games. After a certain threshold is reached (when the system “Found” your correct place), your elo rating will not “solidify” more. It might only become more accurate in finding the correct spot.

That’s why the K-factor is so important: We want to reach that threshold as fast as possible. I think after around 15-20 games every player is where he/she should be. That’s a lot for a single year, but not for multiple years.

[MrRoboto]

@mr_stucifer said in Proposal for a new, ELO-based, ranking system:

I am not sure how, but think it would be awesome if we could implement a possible Bid allowance into drastically different ELO games. Say a 500+ rating difference could get double the usual bid but have the game be worth half the points. This might promote playing between the extremes in skill levels, if useful.

I support this idea. And I think together we can find the sweet spot.

My idea would be to take the average bid up until that game.

And then for every bid above that average, the ELO change could be multiplied by 2%.

Right now in BM, the Allied bid is 18.3 on average.

If I play Axis and give my opponent +30, thats 12 more than average.
If we are at the same ELO level, I would usually gain 40 for a win or -40 for a loss.

Factoring in the bid, I would gain 401.12 = 49.6 (so 50) points, I would only lose -400.76 = 30.4 (so 30) points for a loss too.

An example for players with different ELO rating:

A 1800 wins against 1500.
Ratings change +16 and -16.

With a bid that 12 higher than average, that changes to:

+20 and -12

Or a 1800 loses against a 1500
Usually that is +64 and -64.

But with a bid 12 higher than average, that changes to
+80 and -49

Do you think that 2% per bid is too high or too low? Quite right?

[MrRoboto]

@MrRoboto said in Proposal for a new, ELO-based, ranking system:

That’s why the K-factor is so important:

To be precise: The difference of the K-rating between the first and later games is the important part. That total value of K is not necessarily very important.

Right now K changes from 120 (first 3 games) to 80 in later games. So the first 3 games give 50% more points than later ones.

Lowering the 80 to a lower number would not only enhance the impact of early games compared, it would also narrow said corridor. You would oscillate a bit less around your “correct” rating.

If the difference between the early and the last games is too high, players with slightly more than 10 games might be far off from their correct spot when a couple of those early games are outliers.

[Stucifer]

@MrRoboto Hmm, I like the idea of having the bid tied to the average, does bidding in your experience generally start slightly above average? 2% per IPC seems like it might be a little high, at least for OOB with such a high average bid, going from 40 -> 60 bid might not need to be worth 40% more points.

But in PtV going from 6 to 26 seems like it should be worth 40%. I am not very fluent in BM so I will not hypothesize. Perhaps some sort of relative scale is needed on this aspect as well.

[MrRoboto]

That is a valid point!

It has to be relative to the absolute amount.

And I made a slight error in the calculations above.

If I lose despite getting a higher bid, my loss will be more significantly of course.
The numbers are correct, but I mixed it up a little for winners/losers.

Let me think about a formula that factors in the absolute amount, but now I have to go to bed.

[MrRoboto]

Just entered the criteria of 6 games completed this year.

Only 4 players in PtV
5 players in OOB
12 players in BM4

Maybe we could reduce the requirement to 4 or 5 games completed?
Or we could see how many more games are being finished in these last 2 months

[pacifiersboard]

@MrRoboto

I am sorry indeed for bothering you with this request, but it is not giving this option to me. @mr_stucifer, does it work for you now?

[farmboy]

@MrRoboto it is now 6 for BM and 3 I believe for oob and PTV. Gamerman could confirm the numbers.

[pacifiersboard]

@MrRoboto

imo, bids should keep these two functions:

• determining sides by
• balancing between Allies and Axis (according to players’ individual preferences)

Balancing between different skills I see already covered by usual ELO system. Additional handicaps can hardly easily be ruled without distortion, so can be left to sportsmanship and fun’s cause without reflection in ELO?

Considering the incentive issue we already got that

• top players are already “forced” to encounter weaker players as part of the play-offs

• players with many games have to pick at least three different opponents in order to be eligible for more matches. Maybe this setting is appropriate to be modified for more alternation?

[Stucifer]

@pacifiersboard I made my own document in google sheets, with the 6 columns, entered data and shared the document with Roboto. Then let him copy over onto the master

[Adam514]

@MrRoboto said in Proposal for a new, ELO-based, ranking system:

@mr_stucifer said in Proposal for a new, ELO-based, ranking system:

I am not sure how, but think it would be awesome if we could implement a possible Bid allowance into drastically different ELO games. Say a 500+ rating difference could get double the usual bid but have the game be worth half the points. This might promote playing between the extremes in skill levels, if useful.

I support this idea. And I think together we can find the sweet spot.

My idea would be to take the average bid up until that game.

And then for every bid above that average, the ELO change could be multiplied by 2%.

Right now in BM, the Allied bid is 18.3 on average.

If I play Axis and give my opponent +30, thats 12 more than average.
If we are at the same ELO level, I would usually gain 40 for a win or -40 for a loss.

Factoring in the bid, I would gain 401.12 = 49.6 (so 50) points, I would only lose -400.76 = 30.4 (so 30) points for a loss too.

An example for players with different ELO rating:

A 1800 wins against 1500.
Ratings change +16 and -16.

With a bid that 12 higher than average, that changes to:

+20 and -12

Or a 1800 loses against a 1500
Usually that is +64 and -64.

But with a bid 12 higher than average, that changes to
+80 and -49

Do you think that 2% per bid is too high or too low? Quite right?

I don’t think rating changes should be dependent on bid. Both players consented to that bid, presumably for balance reasons. It’s what both players are satisfied playing with. No need to put a rating factor on that.

[Stucifer]

@Adam514 The primary impulse behind this idea, for me:

Find a way for high-rating players such as yourself to play lower-rated players like me, give them a generous bid, but not lose as many points if they lose.

I learn the most from games I lose and playing high-rated players is useful for me to learn stronger strategies. But I also would probably get walked over with a normal bid. If I underbid that opponent on an average bid and they accept they will steamroll me, but if I accept the average bid they will also steamroll me. So there is an inherent difficulty in finding a bid that works when there is such a large skill difference.

[Stucifer]

Unless the player is generous and gives me a larger than average bid from the get-go. What I’m suggesting is that if there was at least a mild incentive to do so, it might happen more often. Not to call anyone out, but entering over 500 games I see people playing the bottom-ELO players and half the time that player gets a below-average bid, and they are always losing those games.

[oysteilo]

dont complicate things with adding a “correction” for the bid. There is no such bid giving both sides a 50% win chance. Listen to Adam514 here

[Stucifer]

dont complicate things with adding a “correction” for the bid.

I won’t argue, this is likely the sentiment of the majority. I want to add, I think an adjustment for all bids would be overkill.

There is no such bid giving both sides a 50% win chance.

100% true.

But the Econ heart yearns to give incentives for players to have a more even matchup across skill levels. Incentives matter.

A 500-rating difference is an expected 90/10 W/L ratio. If you give your opponent a bunch of extra units at the start of the game, it is more likely than not that W/L ratio would shrink somewhat–but there is a disincentive to accept that, as you would lose significant League ranking for losing to such an underdog. If instead you would lose fewer points from a loss, and gain more points from a victory at this more pronounced disadvantage, there is increased incentive to play the game across the skill tiers.

Is this me having a hammer looking for nails? Perhaps. I am new to League and tend to jump into my hobbies with a profound intensity.

[gamerman01]

Bids are normally used, vast majority of the time, for players to choose sides and their perception of making the game fair. In this case, bids should have nothing to do with rating.

If a bid is used as a handicap (I’ve never noticed this to be the case), to equalize the skill between players, then the door is not slammed shut on affecting ratings. Would be easy enough to set a scale, especially based on average bid because that has been basically agreed on by the whole group.

In other words, if average bid is 18.3, then if you give a 30 bid to your opponent because both agree he’s weaker you get some amount more points. Then you could start playing around with a system that would reward such. That’s just not the way it’s been so far, and as has been said, is quite the complication and could be quite controversial.

And now the rankings would become more subjective, because who knows what scaling factor should be given for what differences in bids.
And in the case of handicaps, now the #1 player could play the bottom player, fishing for points, and with a huge bid he’s no longer 98.8% likely to win (I would say 99.99%, myself, but let’s not go down that road), it’s some chance less than that. Who can determine the bonus to rating for the #1 player giving a 100 bid to the bottom player?

By the way, a 100 bid HAS been granted to another player many years ago, and the one with the 100 bid lost. They will remain nameless.

[gamerman01]

@mr_stucifer said in Proposal for a new, ELO-based, ranking system:

Not to call anyone out, but entering over 500 games I see people playing the bottom-ELO players and half the time that player gets a below-average bid, and they are always losing those games.

(The following is, I’m launching from your point, it is not at all a retort back to your post.)

Thank you, I was going to make this point yet again, but now you’ve given me a head start.

To the complaint that you can lose points with a win.
Those games shouldn’t even be played, because they are not competitive.
To the complaint that you can’t learn unless you play somebody way better than you, I tend to disagree. Watch someone else’s game, or play someone a tier higher than you. A bug doesn’t learn much getting hit by a windshield.
A stronger argument from me is that the better player is putting a lot of time into a game that, as you said, is always being lost, instead of playing a much more competitive game.

The thought behind the complaint of losing points for winning games is that everyone should be able to play everyone. I’m just saying it’s not that simple. In my opinion it is not a great improvement to give the #1 +1 points for beating the bottom player. What a waste of time. If you don’t want to lose points and the #1 player wants to play the bottom player, you could always play that game outside the league.

I’m fine with the system always giving some increase for winning, how can you argue against that?
(Except for the argument that those games are pretty much a waste of time. This isn’t a 20 minute game of chess)

New system, ELO adjusting based on current ratings is great. I’m just saying that an upper player is going to pound a low player every. single. time. And that with ELO, appropriately, top player will get about 1 point, which is appropriate, and my point is the #1 player still won’t play the bottom player if he’s wanting a higher rating, the time sink is totally not worth it, so there will always be the same complaint - top won’t play the bottom. It’s because of the time commitment.

But it’s not about the points. A top player might have a blast destroying/teaching a much lower player. I guess I’m not saying those games can’t and won’t happen, I’m saying the rating system shouldn’t reward such games (and neither the past or the future one do)