CFC Ratings Auditor

[Lucas Davies]

then your memory is faulty. One of the problems (of several) with the bonus points at that time is that they were not reduced for players over 2200 by the k factor. This resulted in some pockets of rating inflation among some of the top players

Is the old formula available anywhere?

[Fred McKim]

Is the old formula available anywhere?

There were several old formulas.

The one we had in place the longest was something like this

gain 40 points in a 4 round tournament you gain 16 bonus points (40-24)

gain 50 points in a 5 round tournament you gain 24 bonus points (50-26)

The bonus point starting point was 24 + 2 * number of rounds over 4

That was the formula in place around 1973 until 19xx when it was changed to something else.

[Roger Patterson]

Is the old formula available anywhere?

as Fred notes, there have been many formulas over the years. Rarely have the changes been made with any analysis. There have also been several occasions when a one time bonus was given out to correct for perceived deflation. There have also been periodically participation points, i.e. points awarded per game played.

A related issue, is that the published formulae did not necessarily match what was programmed, sometimes the result of incorrect programming, sometimes just a mismatch to the public description.

Another related issue is that the rating of low level all junior events is a pretty random affair. Events where there are not enough rated players (usually low level junior active events being rated regular rating) require special treatment which involves the judgement of the CFC business office (at least that's how it used to be, probably the same today). Along those lines, rating this types of events in the regular system introduces some issues.

But you might be interested in this document which was used to set the current formulae. http://www.victoriachess.com/cfc/cfc_rating_doc.htm
You were around at the time but maybe didn't pay attention to CFC administration.

[Vlad Drkulec]

I would like to thank Paul for his many years of service to the CFC. I am not running against him.

Actually, yes you are running against Paul Leblanc for rating auditor. I have seen similar statements from Mahmud and campaign manager Hal Bond with respect to the presidential bid. Lets be real here.

[John Brown]

The easiest way to keep players playing is Just take the 16 points for a loss 8 points for a draw from the Higher rated player. Then give
all your Bonus K points or whatever you think is good for the winner of the lower rated player.

I have suggested this for years but the people at the CFC level are not listening to common sense. They are just killing established ratings. That is one reason players have dropped out. I beat a player 300 points lower than me I get 2 points. But they beat me and I look like I have fallen into a ditch..

[Aris Marghetis]

The easiest way to keep players playing is Just take the 16 points for a loss 8 points for a draw from the Higher rated player. Then give
all your Bonus K points or whatever you think is good for the winner of the lower rated player.

I have suggested this for years but the people at the CFC level are not listening to common sense. They are just killing established ratings. That is one reason players have dropped out. I beat a player 300 points lower than me I get 2 points. But they beat me and I look like I have fallen into a ditch..

I'm curious for your opinion John (we seem to be in similar life stages): would a rating floor be appealing to you? I personally believe that it would be good for retaining longer-term CFC members.

I understand that would induce a mathematical effect, but I'm hopeful for fair countervailing measures?!

[Roger Patterson]

... would a rating floor be appealing to you? .....!

some equivalent effects of introducing rating floors:

1) the CFC would no longer rate players over 60 years old as they are weaker than their floor rating usually (but would presumably still charge a rating fee)

2) players over 60 years old would no longer be allowed to play in the section according to their strength but must play up a section (or two)

3) players over 60 years old would no longer be allowed to win class prizes.

4) other players who are "forced" to play someone over 60 would get a small rating bonus as compensation.

and really, how can you call a rating floor, which means your rating is fixed at some level above your strength and does not change as you play games, a rating?

Anyway, no. I would not find a rating floor appealing.

[Tony Li]

What's the deal with ratings these days? I see people who are like 1900-2000 having one good tournament and just gaining like 200 points. That did not happen back in my day, no siree!

Hi Lucas,

The current bonus system is very generous to tournaments with many rounds, as well as those with a low rating spread.

For example, some clubs have 9-round tournament running over several weekday nights. The bonus threshold for 9 round tournaments is 39 points. The average player would get 15 bonus points for just scoring 6/9, and an additional 56 bonus points for each additional win.

[Tony Li]

The easiest way to keep players playing is Just take the 16 points for a loss 8 points for a draw from the Higher rated player. Then give
all your Bonus K points or whatever you think is good for the winner of the lower rated player.

I have suggested this for years but the people at the CFC level are not listening to common sense. They are just killing established ratings. That is one reason players have dropped out. I beat a player 300 points lower than me I get 2 points. But they beat me and I look like I have fallen into a ditch..

You are the perfect example of a player losing points to underrated juniors. If I remember correctly, you are 600 or 700 points below your peak rating.

P.S. 300 points is 5.5-to-1 favorite, so you get 5 points for winning a game.

[Tony Li]

1) you make a number of statements about the rating system and a hypothetical shock when OTB chess returns but provide no data. Offhand, I don't think many if any of your "Issues with the current system" are actually true. Statements about a rating shock due to vastly improved juniors in a year are completely hypothetical.

2) you propose a number of significant changes that amount to a complete and total rethinking of the rating system but do not propose significant analysis before disrupting the system. The rating system is the CFC's most valuable asset. Any tinkering should be done with a great deal of analysis and simulation. It is true that the governors (now VMs) have occasionally in the past allowed changes on the basis of hand waving arguements but that is not wise and has been destructive in the past.

3) You want to allow low rated and/or young players to have 6 games a day allowed for regular rating. This has nothing do do with unsound mathematics - it is simply the judgement of the CFC VMs that the regular rating should be separate from active play. Will you commit to enforcing the current rules until such time as the VMs agree with your views?

4) given your remark about "Increase the maximum reduction in the provisional rating formula from 400 to 700". I'm not sure you understand the mathematics behind calculating performance ratings. The CFC uses a linearized version of the rating formula which yes, caps out at a difference of 400 points. FIDE uses the full rating formula and caps out at a difference of 700 points but these are different formulas and are not inherently more accurate than each other. The real issue is that when your junior walks into a club of experienced players and loses every game, it is mathematically impossible to determine what the correct rating should be. Using 700 points a la FIDE or 400 a la CFC does not really change this problem.

Hi Roger,

1. I think it is important to stay humble - no one can be great at tinkering. Whether I am right or wrong, having a higher k-factor for juniors will organically work itself out. Rating points will only be added to the system when juniors outperform adults relative to their ratings.

2. I agree we should work towards minimizing tinkering. A higher k-factor a minimal form of tinkering, relative to the bonus system.

3a. There is no basis to limit the maximum number of games per day, especially at lower ratings. You cannot make a better move with more time if your toolset only has 2 or 3 evaluation criteria, and you can only analyze 4 to 5 ply. Abuse by junior organizers can be dealt with by prescribing that this lowest section be part of a multi-section tournament where the other sections have no more than 4 games per day.

3b. Yes, we have been following the rules. We had a 8-round, 2-day tournament for our lowest section last time around.

4. 400 points lower is by definition a 10-to-1 underdog. But a 10-to-1 underdog should score 2.3/25 which is about 330 points lower. So even there the initial provisional rating is 70 points too high. The linearity in the CFC provisional rating formula was probably devised at a time when computational power was more limited. We can do better, without much effort.

Would you be in favor of exploring the Glicko system?

[Tony Li]

I support reverse bonus points as suggested by Erik Malmsten. I certainly need to reduce the amount of points lost to juniors.

Hi Hans,

Paul's work indicates no inflation or deflation overall. Since the bonus system is more generous to higher rated players (improvement happens more slowly but the rewards are the same), it's unlikely that the players you would face are underrated.

Your results are much more likely to be due to fatigue. There is not enough rest time in between rounds. I think I've seen you take byes for the third games on Saturday night, which is a great idea.

[Tony Li]

and really, how can you call a rating floor, which means your rating is fixed at some level above your strength and does not change as you play games, a rating?

Anyway, no. I would not find a rating floor appealing.

I am not in favor of a lifetime rating floor, but a reduced k-factor for seniors seems reasonable.

[Roger Patterson]

Hi Roger,

1. I think it is important to stay humble - no one can be great at tinkering. Whether I am right or wrong, having a higher k-factor for juniors will organically work itself out. Rating points will only be added to the system when juniors outperform adults relative to their ratings.

2. I agree we should work towards minimizing tinkering. A higher k-factor a minimal form of tinkering, relative to the bonus system.

3a. There is no basis to limit the maximum number of games per day, especially at lower ratings. You cannot make a better move with more time if your toolset only has 2 or 3 evaluation criteria, and you can only analyze 4 to 5 ply. Abuse by junior organizers can be dealt with by prescribing that this lowest section be part of a multi-section tournament where the other sections have no more than 4 games per day.

3b. Yes, we have been following the rules. We had a 8-round, 2-day tournament for our lowest section last time around.

4. 400 points lower is by definition a 10-to-1 underdog. But a 10-to-1 underdog should score 2.3/25 which is about 330 points lower. So even there the initial provisional rating is 70 points too high. The linearity in the CFC provisional rating formula was probably devised at a time when computational power was more limited. We can do better, without much effort.

Would you be in favor of exploring the Glicko system?

3b) It is good that you follow the rules but my question was would you enforce them.

3a) Although you follow the rules, perhaps you should talk to Paul about the extent to which some junior organizers will game the system. Your proposal is 6 games / day, 12 games for a regular weekend, 18 games for a long weekend. It has been the judgement of the CFC and/or VMs (so far) that this is not classical slow chess.

4) I have several issues with your argument. Yes it is true that the non linear function could be used. But would it result in any greater accuracy?

- First, your argument only applies to that new player who plays 25 straight games against opposition 400 points above his actual strength to get his regular (as opposed to provisional) rating.. I don't think that ever happens.

- Second, your calculation assumes that the non-linear function is a better fit to reality than the linear function. This is not the case. Although the underlying theory of the rating system gives an expected result given by that function, actual results differ from that curve substantially. See this curve: http://www.victoriachess.com/cfc/stats/expected.JPG This feature is not isolated to the CFC rating system - FIDE exhibits it as well. Judging by that curve, this hypothetical player will score an average of about 5 points, not 2.3 (or a performance rating of 200 points lower). So claiming that the nonlinear curve produces more accurate results in some alternate reality where expected results match that curve is simply not relevant to the real world. (and yes, these actual expected results differing from theory means that you do get a higher rating if on average you play higher rated opposition than if you play lower rated opposition on average).

- Third - you are framing the point estimates as being right and accurate. In fact it is subject to statistical noise - even if the theoretical expected result matched actual results your hypothetical player will score some where between 0 and 5 points or with your preferred 700 point rule some where between 200 and 700 points below the rating of his competitors. That's quite a big range.

5) I have no particular experience with Glicko but have a couple of issues. As per my answer to you in (4) the rating system does not function the way theory says it should. So I question whether the theoretical improvement of a Glicko system would be realized in practice.

A number of years back, there was a posting on this board by an Australian who told a story like this (Australia did have and possibly does have a Glicko system): Players who quit for a few years would come back, because they were rusty they would play badly for a tournament or two. Because they were inactive, their Glicko k factor would be high and they would lose 300 points. Then, they either quit in disgust or, if they kept playing, would shake the rust out pretty quickly but because they were no long inactive, their Glicko k factor would be small, and it would take forever to get their rating back (and so would quit in disgust)

Don't know how true or prevalent that story is, but as I understand it, the assumptions underlying the Glicko approach are that a) less is known about the strength of an inactive player so a higher k value is appropriate and b) the player's rate of change of his strength is slow compared to the number of games being played. It seems to me, that for a player in this story, assumption (b) is not true (as he shakes out the rust quickly even if for a few games he plays below his previous strength)..

ps : I should add, the results of the curve I linked to show why it is important to analyze carefully and not rely on a theoretical understanding of the rating system .

[Aris Marghetis]

some equivalent effects of introducing rating floors:

1) the CFC would no longer rate players over 60 years old as they are weaker than their floor rating usually (but would presumably still charge a rating fee)

2) players over 60 years old would no longer be allowed to play in the section according to their strength but must play up a section (or two)

3) players over 60 years old would no longer be allowed to win class prizes.

4) other players who are "forced" to play someone over 60 would get a small rating bonus as compensation.

and really, how can you call a rating floor, which means your rating is fixed at some level above your strength and does not change as you play games, a rating?

Anyway, no. I would not find a rating floor appealing.

Fair enough, I can't think of an appealing proposal yet.

However, it is something that I just keep hearing about.

[Egidijus Zeromskis]

some equivalent effects of introducing rating floors:

1) the CFC would no longer rate players over 60 years old

Just curious why "60"?