Hi, could someone please explain how the Performance Index is computed and for what purpose it is used in Championship Standings, Promotion to EX, etc? I couldn't find it in the rule book. Thanks.
I'm not sure how it's computed in full, but I believe the reason behind it is to help curb buying a #1 plate by just entering all the races. I don't think in anyway it stops it, but it helps bump up those better riders who can't show up to every race and nock off a few points from those that can afford every race weekend and race.
It seems to be:
[(T-A)/T]*1000 = performance index
where T = the total number of people in your races - including you.
A = the total number of people that finished ahead of you.
Quote from: tzracer on May 08, 2008, 01:19:42 PM
It seems to be:
[(T-A)/T]*1000 = performance index
where T = the total number of people in your races - including you.
A = the total number of people that finished ahead of you.
I reiterate my earlier feelings......OW :banghead: OW :banghead: OW :banghead:
Quote from: backMARKr on May 08, 2008, 01:24:43 PM
I reiterate my earlier feelings......OW :banghead: OW :banghead: OW :banghead:
What is it again that you teach? :)
Quote from: tzracer on May 08, 2008, 01:48:47 PM
What is it again that you teach? :)
History, Government, Sociology, Psych....you know...nice, easy, non abstract math, type subjects :biggrin:
Quote from: backMARKr on May 08, 2008, 01:52:58 PM
History
Serious question to satisfy my curiosity - was there a math requirement for a history degree?
Quote from: tzracer on May 08, 2008, 01:56:19 PM
Serious question to satisfy my curiosity - was there a math requirement for a history degree?
I had to fulfill two math requirements for my Bachelor's in Modern Social History at Southern. I took a Pre-Algebra and an Algebra course.
I tried desperately to get my brother to take my finals for me in both. He's an architect and all that black-art evil math comes easy to him. :err:
Quote from: backMARKr on May 08, 2008, 02:01:05 PM
I had to fulfill two math requirements for my Bachelor's in Modern Social History at Southern. I took a Pre-Algebra and an Algebra course.
I tried desperately to get my brother to take my finals for me in both. He's an architect and all that black-art evil math comes easy to him. :err:
LOL! All this time I did not know I was dealing in the black arts.
ISTR taking about 38 credits of math starting with 200 level calculus as an undergrad (double major - BS physics and math). Even took some while in grad school (MS physics).
I have done worse than figuring out the PI formula.
Quote from: tzracer on May 08, 2008, 02:09:53 PM
LOL! All this time I did not know I was dealing in the black arts.
ISTR taking about 38 credits of math starting with 200 level calculus as an undergrad (double major - BS physics and math). Even took some while in grad school (MS physics).
I have done worse than figuring out the PI formula.
I think at this point, between both my history degrees, I have 35-40 hours of history, most is either Constitutional History or Social History. I have 15-20 hours in Pol Sci too...So I am extra BORING, just ask my students.
:biggrin:
Quote from: backMARKr on May 08, 2008, 02:21:52 PM
I think at this point, between both my history degrees, I have 35-40 hours of history, most is either Constitutional History or Social History. I have 15-20 hours in Pol Sci too...So I am extra BORING, just ask my students.
:biggrin:
More math and physics. Chicks dig physics.
Quote...Chicks dig physics.
Until they hit about 30 that is!
Quote from: tzracer on May 08, 2008, 02:34:30 PM
More math and physics. Chicks dig physics.
Doomed to be uncool my entire life... :lmao:
Quote from: Russell2566 on May 08, 2008, 02:42:33 PM
Until they hit about 30 that is!
And that is a problem?
Quote from: tzracer on May 08, 2008, 02:34:30 PM
More math and physics. Chicks dig physics.
Funny, I remember taking as an undergrad 5 semesters of Calculus, Linear Algebra, Differential Equations, 2 semesters of Discrete Math, and Numerical Analysis, combined with Probability & Statitiscs, Decision Modelling, and Financial Derivatives Calculus as a grad student, and all of that quite possibly having the opposite effect with chicks (except for the chicks in the math classes, who by and large were the type from which attention was not always sought).
Perhaps I should have taken some Renaissance Art classes or something...
Getting back to the main subject, so the Perf Index is really just a rider's results normalized on a scale of 100 per race performance (multiplied by 1000 instead of 100 for some reason), for the purpose of having a standard gauge across events. I'm guessing it is then a straight arithmetic mean for the overall cumulative Performance Index score within a class or overall? Not perfect, given variability in grid position, race positions, difficulty based on grid size, etc, are not factored, but still better than nothing and understandable.
You took all that math and couldn't figure out how to calculate PI :)
Chick dig physics, not math.
PI is the fraction of riders you beat + you times 1000.
I have not checked in a while (and don't really care since I mainly just race USGPRU), but ISTR that the PI is a running total, not averaging the PI from each race.
That is
[total(T-A)/totalT]*1000 where totals are for all races being calculated.
Probably use 1000 so it is like a batting average.
So,help me understand this point system. If your goal is to acheive 400 points in one season to be advanced to expert, then is it your overall points accrued or is it the "adjusted points" that count toward your season points???? I am totally confused right now and my kid (the actual racer in the family) will be devastated if he finds out you have to have 400 "adjusted" points to advance. Mom and I have agreed to be the financing behind next season only if he can make expert by the end of the season. If adjusted points have to add up to 400 to be advanced,I am afraid next season will be a dream but not a reality.
I want to say it's 400 points IIRC, not 400 "adjusted by PI" points to bump to expert....
Quote from: tzracer on May 08, 2008, 05:10:41 PM
You took all that math and couldn't figure out how to calculate PI :)
Chick dig physics, not math.
PI is the fraction of riders you beat + you times 1000.
I have not checked in a while (and don't really care since I mainly just race USGPRU), but ISTR that the PI is a running total, not averaging the PI from each race.
That is
[total(T-A)/totalT]*1000 where totals are for all races being calculated.
Probably use 1000 so it is like a batting average.
No, of course I understood the arithmetic, I was just questioning the validity of the calculation as an accurate representation of performance because of the lack of other quantifiable causal factors, e.g., the assumption of linearity between difficulty (success, i.e., finishes) and grid size - that's all.
But given it's intended purpose and it's limited use, it's probably fine as-is.
My only question was whether the ongoing performance index overall or by class is straight arithmetic mean of the PI results from all previous races in a region or class, which it seems to be.
I believe advancement is based on actual points not adjusted.
So if I competed in every race that I possibly could every race weekend and even with dismall finishes I could still be bumped to EX because I had 400 overall points? Hope that makes sense. Not sure how the bumping up part works. Figure it will be a while before I have to worry about getting to that level since I can only run a partial season this year.
Quote from: AC1108 on May 08, 2008, 11:41:09 PM
So if I competed in every race that I possibly could every race weekend and even with dismall finishes I could still be bumped to EX because I had 400 overall points? Hope that makes sense. Not sure how the bumping up part works. Figure it will be a while before I have to worry about getting to that level since I can only run a partial season this year.
According to section 2.4.4.4 of the 2008 rulebook:
Any Amateur rider who scores 400 points within a 12 month period [will receive a promotion to Expert]
Subsection A:
CCS reserves the right to deny Expert status to any Amateur who meets the Series Championship or Race of Championship criteria [referring to the other subsections of 2.4.4]
and has not shown the experience and ability for expert competition.So, I think that means "yes," you could run a bunch of events, get 400 total points, and be promoted. You could also win a Series Championship, finish in the top 5 of a RoC event, be an Expert in one of the other sanctioning bodies which CCS accepts for reciprocity, or simply do really well as an AM and get bumped mid-season at your request or if CCS notices your performance and offers the bump. However, I'm pretty sure that the CCS staff reviews the bump list at the end of each year, and interim requests, and invokes the "experience and ability" clause as they judge prudent.
Section 8.2.2 and 8.2.3 would indicate that the adjusted points are the riders' points multiplied by the performance index divided by 1000, and that adjusted points are used for the purpose of issuing regional top 10 number plates and championships, EX and AM alike for the latter.
Personally, I wouldn't want to be bumped to EX until my laptimes were such that I wouldn't be a danger to myself and the fast EX's on the track during EX races (although there are many cases now where AM's run with EX's, during 2 wave starts, etc).
Quote from: kl3640 on May 09, 2008, 12:25:56 AM
According to section 2.4.4.4 of the 2008 rulebook:
Any Amateur rider who scores 400 points within a 12 month period [will receive a promotion to Expert]
Subsection A: CCS reserves the right to deny Expert status to any Amateur who meets the Series Championship or Race of Championship criteria [referring to the other subsections of 2.4.4] and has not shown the experience and ability for expert competition.
So, I think that means "yes," you could run a bunch of events, get 400 total points, and be promoted. You could also win a Series Championship, finish in the top 5 of a RoC event, be an Expert in one of the other sanctioning bodies which CCS accepts for reciprocity, or simply do really well as an AM and get bumped mid-season at your request or if CCS notices your performance and offers the bump. However, I'm pretty sure that the CCS staff reviews the bump list at the end of each year, and interim requests, and invokes the "experience and ability" clause as they judge prudent.
Section 8.2.2 and 8.2.3 would indicate that the adjusted points are the riders' points multiplied by the performance index divided by 1000, and that adjusted points are used for the purpose of issuing regional top 10 number plates and championships, EX and AM alike for the latter.
Personally, I wouldn't want to be bumped to EX until my laptimes were such that I wouldn't be a danger to myself and the fast EX's on the track during EX races (although there are many cases now where AM's run with EX's, during 2 wave starts, etc).
If you were to be bumped before you felt you were ready because of lap times or inexperience, CCS will allow you to dispute your advancement, and possibly keep your novice status for another year. 8)
Quote from: hamurobby on May 09, 2008, 08:31:36 AM
If you were to be bumped before you felt you were ready because of lap times or inexperience, CCS will allow you to dispute your advancement, and possibly keep your novice status for another year. 8)
Of course you subject yourself to all the "sanbagger awards" in such a case. :biggrin:
Quote from: Tornado Bait on May 13, 2008, 04:27:08 PM
Of course you subject yourself to all the "sanbagger awards" in such a case. :biggrin:
There are some really fast Amateurs who are in their first full AM season, and they just haven't asked for advancement, though they certainly will make the bump list at the end of the season. Unless you're winning all of the AM races and then decline advancement when you make the off season bump list, it probably wouldn't be sandbagging since you wouldn't be winning too much anyway.
The real sandbaggers are those who cleaned up as AM's, then took a season off or something and come back as AM's instead of EX's and clean up.
Quote from: tzracer on May 08, 2008, 01:19:42 PM
It seems to be:
[(T-A)/T]*1000 = performance index
where T = the total number of people in your races - including you.
A = the total number of people that finished ahead of you.
That formula isn't adding up for me.
Quote from: ktd on May 30, 2008, 10:09:20 AM
That formula isn't adding up for me.
Why not?
10 riders. You finish first.
((10-0)/10) = 1 * 1000 = PerfInd of 1000
10 riders. You finish fifth.
((10-5)/10) = .5 * 1000 = 500 = PerfInd of 500
10 riders. You finish dead last.
((10-10)/10) = 0 * 1000 = 0 = PerfInd of 0
Quote from: kl3640 on May 30, 2008, 01:39:41 PM
Why not?
10 riders. You finish first.
((10-0)/10) = 1 * 1000 = PerfInd of 1000
10 riders. You finish fifth.
((10-5)/10) = .5 * 1000 = 500 = PerfInd of 500
10 riders. You finish dead last.
((10-10)/10) = 0 * 1000 = 0 = PerfInd of 0
I got you there. It just didn't match what they gave me.
That is for one race. Do the average your last race score with the latest race score?
I got to do my last score I think and average them.
Quote from: tzracer on May 08, 2008, 01:19:42 PM
It seems to be:
[(T-A)/T]*1000 = performance index
where T = the total number of people in your races - including you.
A = the total number of people that finished ahead of you.
Ok A = Total number of people that finished ahead of you. If I finished 5th 4 people finished ahead of me. Should A be My position as in your example?
Yes, you could enter a number of races however, you need to score points in order to apply that towards becoming expert.
Here are how the points are broken down per the 08 rulebook:
8.1 CCS POINTS - Points will be awarded based upon the fi nal results of each class
run at each race using the following scale:
First 35 Ninth 16 Seventeenth 8
Second 30 Tenth 15 Eighteenth 7
Third 26 Eleventh 14 Nineteenth 6
Fourth 23 Twelfth 13 Twentieth 5
Fifth 21 Thirteenth 12 Twenty-fi rst 4
Sixth 19 Fourteenth 11 Twenty-second 3
Seventh 18 Fifteenth 10 Twenty-third 2
Eighth 17 Sixteenth 9 Twenty-fourth 1
8.1.1 Points as described above are awarded based upon order of fi nish for all
riders, irrespective of number of entries in the class.
8.1.2 Points as described above are awarded based upon order of fi nish as
well as rider status (Expert or Amateur) except in those classes that
have no divisions
I'm just lost. sorry. Not even thinking of expert yet. Just learning the whole deal.
Supertwins they have me 8th 37points 474.3 PI
Formula 40 12th 35Points 615.4 PI
I was trying to figure the PI out using your formula out of curiosity of what it means.
Quote from: ktd on May 30, 2008, 02:32:34 PM
I'm just lost. sorry. Not even thinking of expert yet. Just learning the whole deal.
Supertwins they have me 8th 37points 474.3 PI
Formula 40 12th 35Points 615.4 PI
I was trying to figure the PI out using your formula out of curiosity of what it means.
I owe you an apology, I made a mistake that may have contributed to your confusion:
In my first example, I used A as the # of riders who finished in front of you. In the second and third, I used it as the absolute finish position. If in fact A is supposed to be the # of riders who finished ahead of you, what you could do is simply change the formula to substitute (P-1) for A where P is your finish position, as such:
( (T-A)/T)*1000=PI, and IF A=(P-1) then
( ( (T-(P-1))/T)*1000=PI
where
T=Total riders on the grid (I'm not sure if they use riders on the grid or entries, I think the former though)
P=Your finish (e.g., 5th place)
So if you finished 5th out of a grid of 10, then PI = ( ( (10-(5-1))/10)*1000=600.
I'm not sure if A is supposed to be the # of riders who finished ahead of you or the position in which you finished, although someone indicated earlier in this thread that it should be the # of riders who finished in front of you. If the former, then, even if you finished last, you'd get something for your PI (presumably a credit for just having completed the race). If the latter, then you'd get nothing for finishing the race dead last.
As far as your question about the PI over multiple events, I believe that it is just a rolling arithmetic mean of all previous PI's, irrespective of any factors outside of A or T. If you want to check CCS's math you could easily look at your previous finishes in a class this season, calculate the PI for each, and then average those PI's (add up all the PI's and divide by the # of events).
Where you may be getting confused regarding your standing in those classes is that you're mixing points with PI, and there is no relationship. As the 2008 Rulebook's section 8.1.1 (quoted previously in another post in this thread) indicates, the points are awarded without respect to the # of entries, i.e., a certain place finish gives the rider the same # of points in each event, regardless of the # of entries in those events.
So a situation could exist where you have a lot of points relative to the # of events run in a class, but a low PI, because of a low # of entries. For example:
In a given class X, there are always 5 entries, and you consistently finish 4th in every event. After 10 events in that class, you'd have:
Points = 230 = (23 * 10)
PI = 400 = ( ( (5-(4-1)/5)
If, on the other hand, there were always 10 entries in that class, and you consistently finished 5th, after 10 events you'd have:
Points = 210 = (21 * 10)
PI = 600 = ( ( (10-(5-1))/10)*1000
The rulebook (Section 8.2) explains the use of points for determining class and overall championships, and the purpose of the Perf Indx (which appears to be limited to Regional Top Ten Numbers assignment and Regional Overall Championships, not individual class championships, if I'm reading the rulebook correctly).
Nobody has been able to tell me how the final P.I., that is multiplied against the points, is calculated.
An average of my per race P.I. is quite a bit higher that what was used to calculate my adjusted points last year.
103 and 131 point differences result with two different ways I calculated final P.I. compared to how CCS does it.
Quote from: SVbadguy on May 30, 2008, 09:37:18 PM
Nobody has been able to tell me how the final P.I., that is multiplied against the points, is calculated.
An average of my per race P.I. is quite a bit higher that what was used to calculate my adjusted points last year.
103 and 131 point differences result with two different ways I calculated final P.I. compared to how CCS does it.
How did you arrive at that - did they actually tell you what PI they used to calc your AP, or did you back in to the PI that they must have used by reversing the formula from the section 8.2.2 and 8.2.3 of the rules, using as one of the factors the non-adjusted points listed for you in the Championship Standings?
Perhaps I missed it, but I could not find in the 2008 Rulebook any reference to Performance Index other than in the below referenced two subsections, and they do not include the formula for calculation of the per-event PI itself, let alone the season average PI; rather, they only addresses how the PI is used for the determination within each region of EX Top Ten Numbers (with the caveat that regions run by affiliate organizations may have different processes for assigning Top 10 Plates) and Overall Regional EX & AM Championships.
...[Top Ten Numbers for Experts/Regional Overall Championships for EX/AM]
... are assigned in each series by overall points earned in all [Expert only for Top Ten Numbers, EX & AM for Overall Championships]
SS, SB, GP, and GT classes, multiplied by the riders [sic]
performance index and then divided by 1000. Expert Top Ten Numbers will be assigned to those riders who rank in the ten highest positions by adjusted points for each region/The rider with the highest adjusted point total will be declared the "Overall Regional Champion" in the Expert or Amateur category.
Note: Affiliated organizations may use their own system for issuing numbers.
It seems to be:
[(T-A)/T]*1000 = performance index
where T = the total number of people in your races - including you.
A = the total number of people that finished ahead of you.
It should be quite clear what A and T represent.
The total PI is not an average of you PI in each race. Total PI is calculated the same as for the individual races. T would be the total number of people in all your races, A would be the total number of all people that finished ahead of you in all races. The PI is a type of average, you do not average averages.
Also not all classes may be used to calculate your total PI. Classes such as supertwins is not used to calculate points towards the number one plate, these classes may not be used when calculating the total PI.
Quote from: tzracer on June 01, 2008, 08:01:12 AM
It seems to be:
[(T-A)/T]*1000 = performance index
where T = the total number of people in your races - including you.
A = the total number of people that finished ahead of you.
It should be quite clear what A and T represent.
The total PI is not an average of you PI in each race. Total PI is calculated the same as for the individual races. T would be the total number of people in all your races, A would be the total number of all people that finished ahead of you in all races. The PI is a type of average, you do not average averages.
Also not all classes may be used to calculate your total PI. Classes such as supertwins is not used to calculate points towards the number one plate, these classes may not be used when calculating the total PI.
Quite correct, A=(p-1), where p= your finish position - my apologies for any confusion.
Also, the calculation of seasonal PI by adding up finishes rather than averaging PI's would make sense, as it allows larger/smaller events to be weighted proportionately.