# Thread: ACF Dec 2003 V FIDE Jan 2004

1. ## ACF Dec 2003 V FIDE Jan 2004

Starter,

I have done a comparison between the Dec 2003 ACF ratings and the Jan 2004 FIDE ratings.

Back when we did the comparison between the ACf Dec 1999 ratings and the Jan 2000 FIDe ratings we ignored anyone who had an ACF rating below 1900. This resulted in an average difference of 150 points. Hence the 150 point uplift added to players ratings prior to the calculation of the ACF April 2000 ratings.

This time we have ignored anyone with a ACF rating below 2050. This time the difference is 68 points.

Now someone is surely going to argue that players lost most of the the 150 points that were added to virtually all players Dec 1999 ratings. If they did this they would be incorrect.

There are currently 212 FIDE rated players who have played games in the ACF System since the Dec 1999 rating period. The average ACF rating of these 212 players back in Dec 1999 after the 150 points was added was 1976.038.
The average rating for this same group of 212 players in December 2003 is 1975.775. A difference of only 0.283.

Therefore this would indicate that there is no loss of 150 points but simply a redistribution of the points amongst the players, a situation that is to be expected unless someone is silly enough to argue that all 212 players are static and have neither improved or declined during this 4 year period.

Since there is no loss of rating points within the ACF pool, it therefore seems that the FIDE pool has inflated by 68 points during this same 4 year period.

2. Whilst everyone has been doing barry's marble puzzle, I have been busy collating the following data.

The following shows the figures for the FIDE January rating list for particular years.

The data shown is in the following order:
a) Year
b) Highest rated player on list
c) The rating of player 100 on the list
d) Number of players over 2600
e) Number of players over 2700
f) Average rating of the top 20 players
g) Average rating of the top 50 players
h) Average rating of the top 100 players

2004 2831 2606 117 18 2727.85 2687.28 2654.21
2003 2847 2598 98 14 2723.55 2683.68 2650.42
2002 2838 2596 90 13 2722.10 2681.74 2647.00
2001 2849 2595 92 12 2721.35 2681.16 2646.67
2000 2851 2595 89 11 2715.55 2675.46 2642.55
1999 2812 2587 83 10 2708.10 2667.34 2634.90
1998 2825 2584 76 8 2705.50 2664.00 2634.80
1997 2795 2580 66 8 2696.00 2657.30 2625.20
1996 2775 2580 65 8 2694.25 2654.40 2623.40
1995 2805 2575 60 9 2687.50 2648.10 2618.55
1994 2740 2565 56 5 2674.50 2638.70 2611.25
1993 2805 2565 54 4 2670.75 2638.60 2609.30
1992 2780 2555 41 3 2657.25 2625.70 2598.45
1991 2800 2545 33 3 2655.25 2620.00 2589.20
1990 2800 2540 29 2 2641.75 2607.80 2579.75
1989 2775 2530 28 2 2634.50 2603.80 2573.00
1988 2750 2520 18 2 2633.50 2597.40 2567.05
1987 2735 2515 13 2 2618.25 2585.70 2557.70
1986 2720 2505 14 2 2619.50 2581.50 2550.45
1985 2715 2500 12 2 2615.50 2577.10 2546.80
1984 2710 2490 17 2 2621.25 2577.70 2540.00
1983 2710 2495 13 1 2614.75 2576.10 2540.80
1982 2720 2495 15 1 2617.25 2580.50 2542.10
1981 2690 2495 15 0 2617.75 2578.00 2544.10
1980 2725 2500 14 2 2621.50 2580.80 2548.10
1979 2705 2500 11 1 2615.25 2577.20 2546.30
1978 2725 2500 12 1 2613.75 2577.90 2547.35
1977 2690 2495 12 0 2613.00 2576.70 2545.35
1976 2695 2490 13 0 2613.75 2573.20 2540.40
1975 2780 2490 18 2 2629.25 2580.20 2544.05
1973 2785 none 14 1 2623.50 none
1971 2740 2480 16 1 2626.00 2583.40 2542.60

3. Hi Bill,

Does all this mean that every player currently on the rating list will receive 68 additional rating points on the ACF March rating list?

4. Possibly.

5. silly question now, but why would players get 68 more points?

6. Because of the inflation by FIDE.

7. oh no another inflation deflation debate ](*,) #-o

8. Debate?

9. Originally Posted by Jeo
Because of the inflation by FIDE.
Well done. =D>

10. Originally Posted by ggrayggray
oh no another inflation deflation debate ](*,) #-o
Pay more attention and re-read the first post.
But more importantly :-k .

11. Originally Posted by Jeo
Debate?
He is probably referring to a debate on the old board regarding whether the ACF ratings were deflating.
However it would appear he has failed to undersrand the facts of the first post and the historical implication of the second post.

Therefore pay no attention to him, he doesnt understand.

12. Originally Posted by Bill Gletsos
Originally Posted by Jeo
Debate?
He is probably referring to a debate on the old board regarding whether the ACF ratings were deflating.
However it would appear he has failed to understand the facts of the first post and the historical implication of the second post.

Therefore pay no attention to him, he doesnt understand.
bill, bill, bill. actually i was trying to anticipate some ppl saying that some or all players should get 68 points added to their acf rating. I had read the post the first time and then reread it after you claimed i should go back and re-read it.

I was also trying to anticipate that old debate again and trying to kill it off before it started 8-[

13. Originally Posted by ggrayggray
bill, bill, bill. actually i was trying to anticipate some ppl saying that some or all players should get 68 points added to their acf rating.
It would appear you seem to think they should not get 68 points added.

If this is the case then you obviously didn't pay as much attention to information posted on the BB or the ACF bulletins as I had believed.

The original post on this board is a carry over from the old ACF BB.

On the old BB I said the following.

the motion passed at the last ACF Council meeting:
That the ACF Rating Officers are authorised to adjust the ACF ratings as they see fit to try and bring the ACF ratings more in line with the FIDE ratings. This correction to take place where determined necessary prior to or at the same time as the publication of the first ACF rating list for each calendar year.
and
However keep in mind the Council also passed the following motion:
That the ACF Ratings Officers are authorised to deduct rating points from players who had been inactive over the period 1980-1999 to offset any anomalies caused by the 150 point bonus added to players back
in April 2000. The method of determination and the number of points to be deducted is left to the ACF Rating Officers to decide
Graham and I are still currently working on this one.
Those motions were also reported in an ACF bulletin last year.

Now it is clear from the first motion that the aim is to try and keep the ACF and FIDE ratings in line as much as possible. THus if there is no deflation in the ACF system but the ratings have divereged by 68 points then there must be FIDE inflation. To remove this discrepancy then obviously points need to be added to the ACF ratings.

14. It would appear you seem to think they should not get 68 points added.
I guess in some ways i dont think there should be 68 points added fide and acf use two different rating systems(as i understand it) so then it makes sense to me that there will be a disparity from time to time. For some reason, I feel that if the acf ratings are going to be increased, this time by 68 points, each time the fide ratings are higher, then we might as well use elo :o

15. Originally Posted by ggrayggray
I guess in some ways i dont think there should be 68 points added fide and acf use two different rating systems(as i understand it) so then it makes sense to me that there will be a disparity from time to time. For some reason, I feel that if the acf ratings are going to be increased, this time by 68 points, each time the fide ratings are higher, then we might as well use elo :o
Then you clearly do not understand. ](*,)
It isnt a glicko V elo issue.
Even when the ACF used the ELO system for ratings calculations there was a difference between ACF and FIDE ratings. This difference increased between 1980-1999 such that in 1999 there was a 150 point difference. Hence the 150 point uplift in April 2000.