A really dumb question: why stage points and percentages

[Chills1994]

The guy with the highest cumulative hit factor for the match in his division wins?

Could someone 'splain that to me?

[AlamoShooter]

I don't think its a dumb question. but as best as I can tell it goes back to the foundation of IPSC/ USPSA

If each stage was worth an equal amount as in 100% points for each stage. with a short stage worth the same as a long field stage. The match would be , could be won on the small stages by speed shooting alone. and the winner could just be Ok at moving and shooting.

[Silver_Surfer]

Good question. I know it is what it is but I have lost matches because of this.

[rvb]

I don't think its a dumb question. but as best as I can tell it goes back to the foundation of IPSC/ USPSA

If each stage was worth an equal amount as in 100% points for each stage. with a short stage worth the same as a long field stage. The match would be , could be won on the small stages by speed shooting alone. and the winner could just be Ok at moving and shooting.

ditto.

a stage w/ only 30 possible points could have an insanely high hf. Imagine a bill drill w/ 30 points in 2 seconds = 15 hf vs a 150 point field course over 20 seconds = 7.5 hf. That makes the bill drill points "worth" WAY more per point than the field course if you just added hf. Would that be right? The % of possible points relates the score (hf) to the level of effort (number of available points). Basically the data is "normalized," which puts the different un-related data (hfs from different stages) on even keel.

-rvb

[Chills1994]

Hooray for Microsoft Excel and its autosum feature.

I did some poking around the 2008 Production Nat's results.

cumulative HF-wise they shake out like this:

1. Bob V 201.9048

2. Dave S 201.463 (wow that was a tight race between first and second )

3. Ben S. 197.1854

4. Angus 182.3464

5. Matt M 169.3371

Now, just for grins and giggles I took Matt M.'s cumulative HF and divided it by Bob V's winning C.H.F. .

The calculator spit out something like 83%, which IIRC is different than the 88% overall matchwise (stage points added together) that he ended up with.

I haven't exactly figured out where I am going with this info. At least not yet.

having come over from IDPA (yeah, I know... you all are doing this ) and the simplicity of its scoring system where like golf, the guy with the lowest score...err.. time... wins.... I have always been puzzled by why USPSA and EZ-win-score converts everything over to stage points and then percentages.

As far as things being normalized...uh... I'm still scratching my head over that one...

If all you're gonna do is add each shooters HF's for each stage together, what difference does it make?

I mean, if you really excell at stationary standards type stuff and get the highest HF for that stage compared to everyone else, shouldn't you be rewarded for that?

And if you are one of the guys who got spanked on the standards type stuff, well, you just discovered what you need to work on, what your weakness is.

I guess what I am thinking of this "normalizing" feature is that it levels out the peaks and raises the valleys. Or those folks whose super high HF's or super low HF's would typically be outliers now get pulled more into the bell of the bell shaped curve when their scores get converted over to stage points/percentages.

I might have to do some more piddling around with Excel and the autosum feature.

At this late hour, things just ain't sinking in like they should and I feel like a dog chasing its tail.

Good night, ya'll!

[HoMiE]

As far as things being normalized...uh... I'm still scratching my head over that one...

If all you're gonna do is add each shooters HF's for each stage together, what difference does it make?

I mean, if you really excell at stationary standards type stuff and get the highest HF for that stage compared to everyone else, shouldn't you be rewarded for that?

It makes a difference because every stage is not "worth" the same amount. Taking the HHF and "normalizing" (not sure if that is the correct word) 'weighs' the stages out based on how many points are available.

I guess what I am thinking of this "normalizing" feature is that it levels out the peaks and raises the valleys. Or those folks whose super high HF's or super low HF's would typically be outliers now get pulled more into the bell of the bell shaped curve when their scores get converted over to stage points/percentages.

Since you are tinkering around with excel, graph out the HF and the Stage Points. It does not distribute normally, or at least it does not look like a bell curve.

[XRe]

It makes a difference because every stage is not "worth" the same amount. Taking the HHF and "normalizing" (not sure if that is the correct word) 'weighs' the stages out based on how many points are available.

This - and the fact that it puts a big emphasis on ... high hit factor stages. Typically, stages that involve real shooting tests are not high hit factor. But, using hit factor as the absolute score means that stages that tend to score a high hit factor are now worth a lot more in the match than stages that have to be run slower or have a lot of running in them, or...

[dajarrel]

If I understand this correctly, the HF will give you an indication of how you did on a SINGLE stage as compared to the other shooters. As each stage has a different test of skills involving more or less targets each has to be scored seperately.

I would hate to know that I was bested in a match because a fellow shooter had an insanely fast trigger finger on one of the "in your face" 12 round stages while in the 32 round field course I smoked him handily. Only because the HF was so high on the short course and low on the field course????

If every stage was a fixed number of rounds with minimal movement and target relocation, adding HF's together would probably work but because all the stages would all be the same test of skills.

But where is the fun in that?

just my opinion

dj

[Jim Norman]

Using just the Hit Factors as your score is not a good idea. Build a match with three stages like El Prez, Bang and Clang and Can You Count and then add in two long 32 round field courses with some really long shots and a couple disapearing targets. HHF on these may be 3-5 where the first three are 12-17. You can trash the Long Courses and still win.

By assigning points, either the available points as determined by the round count (Each shot is 5 points, HHF get the whole of the available and the rest of us get the number of points based upon the percentage of our hit factor vs the HHF) OR assign each stage an equal value (100 Points?) and your "Match Points" are equal to your percentage of the stage winner's Hit Factor.

Method one essentially makes each shot in the match count the same, method two makes each stage or skill set equal.

Many 3-GUn (Multi-Gun) matches use the "All stages equal" method (or a slight variation as in Horner, where a one gun stage is 100 points, a two gun is 125 and a three gun is 150).

Both of these systems work well and generally the top shooter will win in either. We have actually checked one against the other and there are a few flips, but very few and generally they do not affect the outcome of division or class winners.

Me, I would change to the "Add up your percentages" method, but I am not in a position to do so, so I accept the HHF gets all the points and the rest of us get a number of points based on our percentage method. It is a bit harder to explain, but it has been this way so long that the easiest explanation we have found is: Shoot more A's faster and you win.

Jim

[Graham Smith]

Interesting question considering that classifications are strictly based on hit points.

What I do know, based on the limited number of matches I have shot, is that the system in use is tough for me to fully understand. Never the less, by converting to percentages what it does seem to do is to more-or-less "smooth out the curve" and make every stage as equal as possible by ranking the shooters using a consistent scale (1 - 100). And from my limited point of view, it also seems to end up with the better scores at the top and the poor scores at the bottom.

Whether this is "fair" or not is stuff that arguments are born out of.

Then again, life isn't fair and there's not much I can do about that either

[ChuckS]

Interesting question considering that classifications are strictly based on hit points.

I am not sure what you are saying here. Your classifier score is your hit factor. Your classifier % is a ratio of your hit factor to the high hit factor of record for that classifier. Not just points.

Later,

Chuck

[sslav]

Me, I would change to the "Add up your percentages" method, but I am not in a position to do so, so I accept the HHF gets all the points and the rest of us get a number of points based on our percentage method. It is a bit harder to explain, but it has been this way so long that the easiest explanation we have found is: Shoot more A's faster and you win.

Jim

Basing it on percentages is the same as saying that every stage is worth 100 points. This equates short, medium and long courses in value. It is better than just adding up HFs but I think it still falls short in objectively evaluating match performance.

Lets take the following example - a match includes the following three stages. Stages one and two are short courses requiring 8 rounds each. Stage three is a standard exercise consisting of two strings, each stings is 8 rounds. If we go by stage percentages only then the shooter who wins the two short courses has a lead on the shooter who won the standard exercise. Each was the best over the course of two draws and 16 rounds fired. Why does one have a lead in the match over the other? Under the existing system they would be tied in points, which is how it should be.

I think the current system is rather good for all its complexity. I feel that it effectively "grades" you evenly on every single shot you fire during the match.

[Graham Smith]

I am not sure what you are saying here. Your classifier score is your hit factor. Your classifier % is a ratio of your hit factor to the high hit factor of record for that classifier. Not just points.

Poorly worded on my part. What I meant was that it is your hit factor as opposed to your weighted percentage (or whatever it is called) that is used to determine your classification.

Altho, now that I think about it, what is the difference between the percentages used in a match and the percentages used in ranking your classification?

[JThompson]

This is a great question and one I have always scratched my head over... it seems to reward stand and blast over field course, and shooting on the move. I would think it would be the other way round, or equal.

[ChuckS]

I am not sure what you are saying here. Your classifier score is your hit factor. Your classifier % is a ratio of your hit factor to the high hit factor of record for that classifier. Not just points.

Poorly worded on my part. What I meant was that it is your hit factor as opposed to your weighted percentage (or whatever it is called) that is used to determine your classification.

Altho, now that I think about it, what is the difference between the percentages used in a match and the percentages used in ranking your classification?

Your match stage percentages are based on the ratio of your hit factor to the high hit factor for the stage. You get that fraction of stage points for that stage. If the HHF is 10 and you get a 5 you get 50% of the max available points for that stage. The points from all the stages of the match are added up to get your match points. Your match percentage is the ratio of your match points to the highest match points.

[Lee King]

Poorly worded on my part. What I meant was that it is your hit factor as opposed to your weighted percentage (or whatever it is called) that is used to determine your classification

Your classifier score is for a single stage as opposed to a match where you have anywhere from 3-10+ wildly disparate stages. Every person who has shot any given classifier was faced with exactly the same challenges (presumably). Maybe someone could enlighten me as to how the top % is determined. Is it simply the 1 guy who has the highest HF on that classifier? Or is it a combination of the top X shooters?

One could argue that, because it generally takes 6 classifiers (not counting initial) for a shooter to be classed, why shouldn't the classifiers themselves be weighted? I.e. Baseball Standards (3-14) vs. Can You Count (6-03). If you have a MD who is predisposed to always choose the hoser classifiers could your classification be artificially high? But don't forget if conditions are right, your major match final % itself can be used as a classifier score.

[ChuckS]

Maybe someone could enlighten me as to how the top % is determined.

That very subject is currently being flogged to death here: http://www.brianenos.com/forums/index.php?showtopic=74817

[Nik Habicht]

Graham,

Hit Factor as it applies to a club match and to classification:

El Prez is the classifier. You shoot a 4 HF. A local B-Class wins the stage in your division with an 8 HF. You shot 50% of his score, earning 30 of the [60] available points, which are added to the other stage's points you earned to determine where you finish in the match.

Your 4 HF is submitted to Sedro Woolley and entered in the database. The National HHF for El Prez in your division is 12. The update runs and a 33.3% score is entered for you....

Thw difference between the two numbers is that in the local match you're being measured against who showed up that day and their performance on that stage. For classification, you're compared a National Standard....

[Lee King]

To add a little to what Nik said and compare to other methods of classification, I shoot pool in the APA. Our handicaps (equivalient to classification) are calculated based on your last 10 wins and how many times to the table it took you to win them. But because you rarely play outside your home area, your handicap is VERY local. It's a problem when/if you play well enough to get a slot to the nationals. A good friend of mine is one of the top dogs around here and and equivalent to a M shooter (in our sport). He got SLAYED by a much lower handicap (C shooter equiv) when he got out to the nationals. I'm sure there could be better ways to manage a classification system. But of the two I have experience with, IF you're going to have handicaps, I like that they are national and somewhat standardized. I feel confident a C shooter here is a C shooter anywhere.

[rvb]

I realize normalize may not have been the correct word. I HATED stats and probability in both undergrad and grad school. boring stuff. but I think you understand the point I was trying to make.

Another thing to consider.... two stages, a 6 rounds 15 hf stage and a 30 round 7 hf stage. Compare what happens if a gun pukes before the first shot so they are both zero'd? Would you think it's "fair" to loose 15 "hf points" for not taking 6 shots vs losing 7 "hf points" for not taking 30 shots? The current system weights the points appropriately, imo.

-rvb

[LJE]

The guy with the highest cumulative hit factor for the match in his division wins?

Could someone 'splain that to me?

There is no such thing as "CUMULATIVE HIT FACTOR" for a match. High hit factor is used ONLY TO CALCULATE the number of STAGE POINTS awarded for a specific stage. Stage points are totaled to determine a shooters MATCH POINTS. It is the shooters MATCH POINTS, or "CUMULATIVE STAGE POINTS" that defines the match winner.

LJE

[rgkeller]

The present system weights the importance of each shot in a match equally.

[professor]

Another aspect of the HHF scoring is the way penalties and procedurals affect your hit factor.

If you miss a shot in our sport, you can make it up in maybe 2/10 to 3/10 of a second [assuming you have the bullets in your gun and you realize you missed the shot while still in a position to make it up]. If you don't make it up, it is a deduction of 10 points on your point score, and another 5 off because you didn't score the alpha that you could have gotten with the makeup shot. That 15 point deduction causes a decrease in your hit factor for the stage which depends on the total points available for the stage, and the time that you took to shoot the stage. On a short course with only 30 points, that single miss will cost you half your potential points, and cut your hit factor for the stage in half. On a 150 point field course, the same miss will only reduce your potential points by 10 percent, so your hit factor for the stage only goes down by 10 percent.

Other sports [bianchi cup, IDPA, etc.] penalize you with extra time added for a miss or for not scoring an alpha hit. A miss on any target "costs" you the same whether its in a speed shoot or in a field course. Those sports place a much higher premium on alpha hits and on not getting misses, nohits, and procedurals than USPSA does. After doing a lot of comparisons between scoring methods, our hit factor system is a lot more forgiving of misses/non-alpha hits/nohits/procedurals than any other scoring method. In essence, the scoring method rewards shooting fast, if not perfectly accurately. Of course, the difference between the top competitors can come down to a fractional point, but a single non-alpha doesn't knock you out of the possibility of winning the match [as happens in Bianchi Cup].

[DrShooter]

Hit factors are not good to work with when combining scores as many have pointed out. Especially if a fixed-time stage is in the mix. There, your hit factor is equal to your points. Try normalizing a HF=119 stage with a 32 round HF= 3.6 stage. Going through the points available and order of finish route does a good job of handling the different meanings of HF for a whole match.