Do you plan to display clan icons next to nicknames? Small thing but I'd like it. :p

It's on our list. But has a lower priority than most of the other items.

I can now see that I've never beat a player above 1500 rating, damn! Anyone else see "Invalid Date Invalid Date" ?

I don't see this on my machines. We'll get in touch with you soon to figure out what's going on.

It's on our list. But has a lower priority than most of the other items.

you start to sound like fizzer and his not immediate roadmap! :D But honestly guys, great job on this ladder! The rotating template system makes it very enjoyable to play without getting bored of the same template all the time! Keep up the good work! :)

Edited 11/11/2016 17:16:37

Firefox version was old; updated and now it's fine (no more invalid date)

Edited 11/11/2016 17:24:28

you start to sound like fizzer and his not immediate roadmap!

:O. You just bumped the priority on clan icons now :P
But in all seriousness, our list isn't too large and most feature requests will materialize sooner rather than later.


@ViralGoat,
Glad it works for you now.

somehow i can't see anything from that latest update when i open the ladder page. Not on my laptop or my phone which use different browsers

It sure was around the corner. Just got it in and I think I've got a second one on the way :-P But I hope Turtle doesn't see this post because I might pay for my overconfidence.

Edited 11/11/2016 23:56:04

somehow i can't see anything from that latest update when i open the ladder page. Not on my laptop or my phone which use different browsers

Try deleting your browser cache. You can also press Ctrl+Shift+refresh on Chrome.

Awesome, may I ask for some implementations:

1. Clan Icons (HighScore)
2. Nation + option to sort by nation

I have two questions regading the elo-system:
Which value does K have?
How do you plan to make sure, that there is no inflation/deflation in the elo-system?

Awesome, may I ask for some implementations:

1. Clan Icons (HighScore)
2. Nation + option to sort by nation

Could you elaborate what you mean by highscore? We're working towards clan icons and that'll be available shortly. It is not possible to determine a player's nationality from WL APIs. I could try to go scrape player profile pages, but not too keen on that at the moment.

I have two questions regading the elo-system:
Which value does K have?

K=32.

How do you plan to make sure, that there is no inflation/deflation in the elo-system?

I picture this system as a "closed" one. The amount of rating points available are always proportional to the number of games played and the player count. When new players enter the system, they start at a base rating which fluctuates based on their performance. However, the points available in the system does not vary much.

The only case when points "leave" this system(which can lead to deflation) is when a high ranked player decides to leave the ladder and take their earned points with them. However, games expire every 5 months, so all these points are "returned" to the system after that.

With highscore I ment: http://md-ladder.cloudapp.net/allplayers

However, games expire every 5 months, so all these points are "returned" to the system after that.

So the skill of a game will be redistributed after 5 month. How do you handle this exactly?

Is it like this

01.01.2017
A (1500) vs. B (1500) 1:0
=> A 1516, B 1484

30.05.2017
A: 1800
B: 1200

01.06.2017 (no games inbetween)
A: 1784
B: 1216

Or do you calculate new elo based on the not expired games (which would effect lots of other players)?

With highscore I ment: http://md-ladder.cloudapp.net/allplayers

Do you mean you want to see something different on that page?

Or do you calculate new elo based on the not expired games (which would effect lots of other players)?

Yes. Every 2 hours, I recalculate Elo based on unexpired games from scratch(assuming everyone is rated 1500).

Edited 11/12/2016 17:05:44

With highscore I ment: http://md-ladder.cloudapp.net/allplayers

Do you mean you want to see something different on that page?

Would just be nice to have a column of clan icons and being able to sort players by that. Always nice to know which player belongs to which clan and rate clan activity (e.g. for those who are searching).

Or do you calculate new elo based on the not expired games (which would effect lots of other players)?

Yes. Every 2 hours, I recalculate Elo based on unexpired games from scratch(assuming everyone is rated 1500).

I am no expert of the elo-system, but this may result in the following:

automatism: players tend towards 1500 elo
a) I need to play a lot of games to get a high elo.
b) Players, who do not play a lot of games, may not be rated accurate.

At the one hand a) makes sure, only active players are ranked high. On the other hand activity may substitute skill-level in some way. Not sure how big this effect is, but it may depend on how big the player pool is.

No big problem right now, but a thing one should observe in the future. It also may take some time until the system is really balanced (as all started with 1500 elo).

I see no reason to modify elo with expired games, elo only modifies taking into account the opponent's elo (and yours) in the game you are currently playing, you can forget about old games and your rating will still increase/decrease according to your current skill level. I don't see any benefit for it, maybe me being a chess players makes me like that system ^^U

automatism: players tend towards 1500 elo
a) I need to play a lot of games to get a high elo.
b) Players, who do not play a lot of games, may not be rated accurate.

At the one hand a) makes sure, only active players are ranked high. On the other hand activity may substitute skill-level in some way. Not sure how big this effect is, but it may depend on how big the player pool is.

No big problem right now, but a thing one should observe in the future. It also may take some time until the system is really balanced (as all started with 1500 elo).

Mostly agree with all your points. The player pool is steady at the moment and has around 75-80 active players. If you have few games, your rating maybe inaccurate. But this is true of all rating systems in my opinion.

It is not guaranteed that activity will give you a high rating though, as every additional game you play can drag you down or boost you up. I think active players will be closer to their "true" rating. You can reach a 1600-1700 Elo if you are semi-active though with a good streak of 10 games. But to reach higher ratings, you have to consistently perform.

---

To address the problem of ratings tending towards 1500(assuming the average win rate is 50-50), I'm contemplating the introduction of a new element to the rating system. If we agree that playing more games leads to players reaching their true Elo, I need to provide incentives to stay active.

I was thinking of adding a "rating boost" per game(say +3 or +4) played, up to a certain number of games. This concept is similar to how the seasonal ladder works, where you get bonus points for playing a sufficient number of games.

However, I need to cap this to a certain game count as I don't want someone with 200 active games getting a boost of 200*4 = 800 points! I'm leaning towards capping the game count at about 40(so max rating boost = 40*4=160). This boost is obviously an artificial boost used only for ranking. It is not used by the matchmaking system when looking for possible opponents.

This also discourages players from making "runs" as you see on all other WL ladders. Runs lead to inflated ratings and points "leaving" the system which is obviously a bad thing.

I'd love to hear other opinions on the pros and cons of this approach, before I make sweeping changes to the rating system.

Edited 11/12/2016 17:52:04

As I said, if you don't adjust elo from expired games, it could solve some problems, for example the "runs", even if you leave your elo is saved, you will start with the one you had. If you want to avoid a player having a big initial ranking after the initial 20 games, make a lower K for those games (16?) and change it latter, after you have an official ranking.
Changing K-values also help with activity problems (some of them pointed by Krunx), you can change the K-value depending on the activity. For example, in the regional elo system we use in catalonia, all K-values have that (with K=16 and the activity modification is +-3, so same level players can have from 13 to 19 depending on activity). Not sure if a variable K it's easy or not to implement.

If you don't like not expiring games because you don't one someone who don't play anymore on the ranking, make a "if you don't play for 6 month, your elo is lost" but, to avoid runs and so, if they return they will start with ana ctual elo and no the provisional 1500. The starting elo could be "old ranking - 200" or something like that, that way you will start playing against players not that far from you skill level, and if you still have it, recover it quick. Not sure of how to implement it, maybe it's difficult. But with the initial-K correction, maybe this is not necessary.

Edited 11/12/2016 19:17:21

As I said, if you don't adjust elo from expired games, it could solve some problems, for example the "runs", even if you leave your elo is saved, you will start with the one you had.

While I agree with this, the problem is that runs usually tend to be on a new accounts. So the Elo is never saved for such accounts. Variable K does help with this though.

Another problem with having all games included is that it takes a long time! We currently have about 386 games finished in about 2 weeks. Projecting this out, I don't like the idea of computing Elo after one year with so many games. Expiring games improves running time of the algorithm too.

One potential fix to the long running time, is to update the previously computed Elo using the recent games, but this has other drawbacks. If there is a bug in the system and I need to make a game disappear, it is hard to do as the previous rating will need correction. On the other hand, running a fresh Elo computation every time, does not have this problem.

If you want to avoid a player having a big initial ranking after the initial 20 games, make a lower K for those games (16?) and change it latter, after you have an official ranking.
Changing K-values also help with activity problems (some of them pointed by Krunx), you can change the K-value depending on the activity. For example, in the regional elo system we use in catalonia, all K-values have that (with K=16 and the activity modification is +-3, so same level players can have from 13 to 19 depending on activity). Not sure if a variable K it's easy or not to implement.

This sounds like a good addition to the system. Could you elaborate on how the K varies by activity? Would it be something like if

0  < gamecount < 10, K= 32 - 15 = 17
10 < gamecount < 20, K= 32 - 10 = 22
20 < gamecount < 30, K= 32 - 5 = 27
30 < gamecount < 40, K= 32

Some updates:

• Added clan icons
  Icons for clans and players' clan affiliations are updated once a day. It may take up to 24 hours for changes to reflect on the CLOT. If a player joins a new clan, leaving and rejoining the CLOT will update their clan tag as well.
  
  
  
  
• Updates to player page.
  The veto menu is hidden by default and can be viewed by clicking the "Change Templates" button. There is also a gaping hole on the right of the page. Wonder why ;)
  
  
  

Edited 11/12/2016 20:46:30

This sounds like a good addition to the system. Could you elaborate on how the K varies by activity?

In fact it's the opposite, the more activity the lower the K.
For the initial games I would use:
- If you can limite the max games to 5 --> k=16
- If you can't change the limit only for initial games --> if nº of games <6 then k=16 else K=10

For normal games, after you have a rating:
A = (finished games in last 30 days)/30 = average finished games per day during 30 days
B = (finished games in last 90 days)/90 = average finished games per day during 90 days
C = (2A+B)/3 <-- Activity
If the player has less than 90 active days, C = total games / total days

I though about A for 60 days and B for 180 but...maybe too long?

And then modify the K with C into account:
K = 32 - 5C

This is an example, not sure what's the normal activity...for example, MotD has 54 games in half a month (roughtly), so 100 a month, but he has a lot of activity, I don't think that's normal :P That would be A=3.33. If he doesn't lower the activity, K=15. Unlikely someone will have lower K's than that.

I have finished 11 games in 12 days, let's say A = 1. Playing 3 games at a time but playing quick, not sure if this is "normal". If I keep that activity my K is 27, not much variation.
If we consider my activity "normal" then it's ok, if we consider it low or high the formula should be reviewed. It's a very simple one, obviously it can be improved, but I like the activity formula ;)



Another problem with having all games included is that it takes a long time! We currently have about 386 games finished in about 2 weeks. Projecting this out, I don't like the idea of computing Elo after one year with so many games. Expiring games improves running time of the algorithm too.

You use all the games to compute elo? You only need the last ones. Maybe the computer check all of them to see which ones finished since last update? In that case, if you have a "expire variable" to avoid expired games, change it to "checked games" and the computer only look for "not checked ones" and:
Elo = current elo +"not checked games elo"

We need to think of something to improve this because the expiring games will end in people losing elo even winning if they or the others lower activity (and not all people will be super active continuosly).

P.D. Thanks for your hard work!

Edited 11/12/2016 21:38:17

Ah. A lower K for active players ensures lesser fluctuation, so I see why you are recommending it for the active players. But doesn't this encourage runs? Once you have 100 games, no matter what you do, your rating is very stable and players feel like they're not making progress even though they are winning.

On the other hand, you can get an inflated rating by playing just 20 games. If we adopt such a system, I feel like we need to encourage activity too(which is why I was suggesting adopting the "bonus points" used by the seasonal ladder.)

We can tweak the constants in the formula after observing the ladder for a month or two.

You use all the games to compute elo? You only need the last ones. Maybe the computer check all of them to see which ones finished since last update? In that case, if you have a "expire variable" to avoid expired games, change it to "checked games" and the computer only look for "not checked ones" and:
Elo = current elo +"not checked games elo"

Yes, I use all games. The reason for this is

One potential fix to the long running time, is to update the previously computed Elo using the recent games, but this has other drawbacks. If there is a bug in the system and I need to make a game disappear, it is hard to do as the previous rating will need correction. On the other hand, running a fresh Elo computation every time, does not have this problem.

Yes it encourages runs. But it is also more accurate, since a rating system know less about a player who plays less games. :(

Online chess has had this problem too, that players makes new account to get a better rating. Some site solved this by being very strict on alts (particularly on top/leaderbords players) The goal is to get like RL chess, where you...only have one human/account, thus only one rating. That means banning anyone who uses more then 1 account from the ladder :/