Fargo: Influence of robustness on performance calculation

[stewie]

Paging Dr. fargo: Just curious, no hard feelings. Is my performance rated different, based on the robustness of my opponent?

I lost against a much lower ranked (almost 200 points) player on the hill. His robustness was 7. Do I have the same performance now as loosing against the same fargo with a robustness of 500+? That would sound a little unfair.

 

[Bob Jewett]

Paging Dr. fargo: Just curious, no hard feelings. Is my performance rated different, based on the robustness of my opponent?

I lost against a much lower ranked (almost 200 points) player on the hill. His robustness was 7. Do I have the same performance now as loosing against the same fargo with a robustness of 500+? That would sound a little unfair.

Not Dr. Fargo, but.... The calculation of ratings finds the most likely ratings for all players that explain all the wins/losses. The system knows that your opponent's rating is poorly known. If you have a robust rating you will only move a little and your opponent will move a lot. You can think of robustness as the "strength" or "stability" of your rating.

 

[Black-Balled]

And 7 is about a low a robustness as one can be assigned.

 

[stewie]

Not Dr. Fargo, but.... The calculation of ratings finds the most likely ratings for all players that explain all the wins/losses. The system knows that your opponent's rating is poorly known. If you have a robust rating you will only move a little and your opponent will move a lot. You can think of robustness as the "strength" or "stability" of your rating.

You might not be Dr Fargo, but Professor Bob is always very helpful as well!

 

[hang-the-9]

Paging Dr. fargo: Just curious, no hard feelings. Is my performance rated different, based on the robustness of my opponent?

I lost against a much lower ranked (almost 200 points) player on the hill. His robustness was 7. Do I have the same performance now as loosing against the same fargo with a robustness of 500+? That would sound a little unfair.

You are not going to be adjusted much, but if someone 200 points under you came that close, with no other data really, they will be. A 7 is nothing in Fargo, they played one race to 7 that was entered in the system. I have lost 5-0 to someone that is at least 50 points under me normally day to day shooting, if that was their own entry, they would be 100 points over me.

 

[mikepage]

Paging Dr. fargo: Just curious, no hard feelings. Is my performance rated different, based on the robustness of my opponent?

I lost against a much lower ranked (almost 200 points) player on the hill. His robustness was 7. Do I have the same performance now as loosing against the same fargo with a robustness of 500+? That would sound a little unfair.

Other good answers.

Let's make an example. You are 550 with hundreds of games.
You lose 6-7 to opponent who is 350 with 7 games. (Perhaps those 7 games are a 1-6 loss to a 650).

What happens tomorrow?

(1) Your rating basically unaffected --there is really no new knowledge about how you play
(2) Opponent's rating goes up maybe to 500 with a robustness of 21 games

But that match is still in your record and while there are no consequences now, there may be later.
Suppose, for instance, that opponent plays several hundred games over the next few months that reveal he really does play at 350 speed.
Alternatively, suppose several hundred games reveal he really plays at 650 speed.

Your 6-7 loss to him would tend to ding you in the first instance and bump you a bit in the second. In a sense our record is a stock portfloio, and we hold shares in our opponents.

 

[stewie]

So, you are saying this match still makes my rating change at a later point, once my opponent became established? Depending on how he or she changed? Which should then be less of an effect the longer it takes him/her to get established, I guess?

 

[Rocket354]

Is there some element in the calculation to discount the low-robustness match? I'm envisioning someone who develops as a player quickly, perhaps getting most tabletime away from fargo-rated matches. So at a 7 robustness the player was really a 350-400 but then improves dramatically over a couple years and by 200 robustness is a 550-600. Would the system know the difference between such a player and one who was 550-600 the entire time?

 

[Bob Jewett]

Is there some element in the calculation to discount the low-robustness match? ...

Yes. This is explained above in Mike Page's post. A player with only a few matches is an unknown quantity and his matches are deeply discounted. But later, when his speed is determined more accurately after he has a lot of matches/games recorded, all of his matches are included with full effect. The calculation is redone every day and includes every game recorded.

 

[Rocket354]

Yes. This is explained above in Mike Page's post. A player with only a few matches is an unknown quantity and his matches are deeply discounted. But later, when his speed is determined more accurately after he has a lot of matches/games recorded, all of his matches are included with full effect. The calculation is redone every day and includes every game recorded.

The question is whether the previous matches are still discounted. In the given explanation, it sounds like it is assumed if he progresses to a 600 level, that is what he was in his early matches. My question is can the system, at least to some degree, recognize when a player has demonstrated remarkable improvement when it recalculates the entire body of work.

If I played an actual-ability 400 guy a year ago who evolves into an actual-ability 600 guy today, are my matches against him a year ago really going to assume he was 600 then, too, because his robustness was super low?

 

[Bob Jewett]

The question is whether the previous matches are still discounted. In the given explanation, it sounds like it is assumed if he progresses to a 600 level, that is what he was in his early matches. My question is can the system, at least to some degree, recognize when a player has demonstrated remarkable improvement when it recalculates the entire body of work.

Matches are discounted with age but other than that the player has only a single rating. He does not have a "two years ago" rating. That means his matches from two years ago will be treated at his present rating but somewhat discounted for age.