How do you determine match points by hand?

[Blueridge]

I am trying to figure out how to by hand determine match points. I cannot find a method described anywhere, but maybe I am not looking in the right place. I look at the match results and cannot figure out how it is done. I looked in the rule book, but could not divine any help there.

[HoMiE]

(points - penalties) / time = hit-factor for every competitor

the highest hit-factor wins the stage and gets 100% of the stage points

you then take your hit-factor diveded by highest hit factor to get percentage and multiple by stage points to get your stage points.

Example: Stage has 10 IPSC targets, 100 points possible

Shooter A - 100 Points / 10 seconds = 10 HF

Shooter B - 90 points / 12 seconds = 7.5 HF

Shooter A wins stage and gets 100 points

Shooter B is 7.5/10 = .75 = 75% = 75 stage points

This is done for each division, for each stage, then add them all up.

Hit-factor and stage points are usually carried out to 4 decimal places

Edited October 9, 2007 by HoMiE

[LChico]

I am trying to figure out how to by hand determine match points. I cannot find a method described anywhere, but maybe I am not looking in the right place. I look at the match results and cannot figure out how it is done. I looked in the rule book, but could not divine any help there.

This is copied from a pamphlet I give to new shooters at our club. You can see all the information at New Shooter Info on my website. I tried to give examples that would make sense to someone new. Many did not understand how shooting all A's on a stage worth 60 points did not automatically translate into 60 stage points once the stage results posted.

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To calculate HIT FACTOR, divide your points by the time. Hit Factor tells you how many points you are earning per second. If you took 30 seconds to shoot a 60 point stage, you have a hit factor of 2.000, and if someone else took 10 seconds to earn those same 60 points, his hit factor is 6.000.

Stage Percentage is calculated from Hit Factor. The competitor with the highest hit factor gets 100% for the stage, and the STAGE POINTS for the shooter with 100% will always be all the points available for that stage.

The Stage Winner is the shooter with the highest HIT FACTOR. All the other shooters are ranked below the stage winner, in order of HIT FACTOR. To get a Stage Percentage, your hit factor is divided by the highest hit factor for the stage. The total number of stage points that you earned for a stage are based on the total points available, multiplied by your stage percentage. Going back to the example above, your hit factor of 2.000 is 1/3 of the fellow who shot 6.000, so if he won the stage & got 100% (all 60 points), then you shot 33% of the leader, and earned 20 stage points.

Another example, a Stage is worth 100 points. You shot real carefully, but real slowly. You earned 100 points for the stage. The fellow who was first place for that stage only earned 80 points, but was fast. Once hit factors and stage percentages are calculated, you are at 50% for the stage, and the fast fellow is at 100%. The stage points will only award you 50 STAGE POINTS, (50% of 100) and the fast shooter gets 100 STAGE POINTS.

At the end of the match, we add up the stage points for every shooter, and get MATCH POINTS. The shooter with the most match points wins, and gets awarded a 100%. Your match point total is divided by the match winner's total match points. This is how we calculate a total MATCH PERCENTAGE.

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Hope that helps.

Linda Chico (L-2035)

Columbia SC

[mactiger]

Not exactly.

For hand calculation--

Hit Factor = Total points shot-penalties (if any) / time. Truncated, not rounded, to 3 decimal places

e.g.: 112 points - 10 points (procedural)=102 points, shot in 16.55 seconds. 102/16.55=6.163. HF=6.163 (points per second)

Stage Factor= the total points possible for the stage, divided by the high hit factor (HHF)= Stage Factor (SF) truncated to 3 decimal places

e.g.: if the total points for the stage are 120, then SF for the stage is determined by dividing 120 by the High Hit Factor.

Assume the HHF is 8.152. Therefore, the SF is 120/8.512 = 14.097

Stage Points = HF X SF, for each competitor.

e.g.: 8.512 x 14.097= 119.996, which is rounded to 120 for the person who "won" the stage.

The remaining Hit Factors are multiplied by the Stage Factor to determine stage points.

For the competitor above, with the HF of 6.163, his stage points are: 6.163 X 14.097 = 86.879

This is "grading on the curve", or statistical normalization--comparing everyone's HF to the HHF in order to get a points value.

Then, the points for each competitor are summed, giving total match points. Percentage of overall finish is determined by dividing the competitors match/stage points by the stage winner's points, or the match winner's points.

EZWinScore does carry these out to 4 decimals, I think. I believe that they are still truncated, not rounded, within the program.

Anyway, it's the way that the person who shoots the most points in the least amount of time is determined to be the winner.

Hope this helps.

Troy

[Badkarma]

Page 5 of the our club's 101 booklet.

"Scoring

An explanation of the mystery.

????????????????????????????????

As in the days of yore...only those who have shown themselves to be worthy (or had a calculator) were given the secret to scoring a stage. All others were deemed too foolish to be given the task. Thus it went for many years...shooters doomed to be ruled by the interpretations of others! In this age of darkness there was seen a glow of truth,honesty and education, and so it is passed to you. Carry proudly the torch of knowledge.

1. A shooter’s score* divided by time results in a value called the hit factor.

2. The highest hit factor for the stage is deemed to be worthy of the full points possible.

3. All other hit factors are a percentage of the high hit factor and receive the appropriate percentage of the possible score. This value

becomes your match points for the stage. [(your Hit factor/ the highest hit factor) x points avaiable for the stage.] Repeat for each

stage.

4. Match winners are determined by the person with the highest number of matchpoints."

[Blueridge]

I thank all for the explanations that they have given to clear my confusion.

[professor]

Not exactly.

For hand calculation--

Hit Factor = Total points shot-penalties (if any) / time. Truncated, not rounded, to 3 decimal places....

Troy

"Not exactly" indeed.

From the "Bible" [current edition of the January 2004 Edition Rule Book]:

9.2.3.1 A competitor’s score is calculated by adding the highest

value stipulated number of hits per target, minus penalties,

divided by the total time (recorded to two decimal places)

taken by the competitor to complete the course of fire, to

arrive at a hit factor. The overall stage results are factored

by awarding the competitor with the highest hit factor the

maximum points available for the course of fire, with all

other competitors ranked relatively below the stage winner.

9.2.5 Stage results must rank competitors within the relevant Division

in descending order of individual stage points achieved, calculated

to 4 decimal places.

9.2.6 Match results must rank competitors within the relevant Division

in descending order of the combined total of individual stage

points achieved, calculated to 4 decimal places.

Note that this edition of the rule book doesn't discriminate between hand calculation and calculator computation. It just specifies time to the nearest 0.01 seconds and stage points "calculated" to 4 decimal places.

Even people talking about "hand" calculating stage results are usually talking about using a pocket calculator to do the division and multiplication. And the majority of calculators automatically calculate to the inherent capability of the internal processor, which is typically 10 significant digits.

As an engineer, starting out in the 60's, we routinely used slide rules that resulted in multiplication & division calculations with 3 significant digits. "Hand calculating" really was multiplying out numbers with paper and pencil, and long division using all the significant digits you needed to achieve a stipulated precision.

When I started in this sport, I was taught the "hand calculation" method of getting hit factors and stage points, etc. And I think it was stipulated in the rulebook as Mac stated above, 3 decimal digits, truncated rather than rounded. [Just as power factor calculations still truncate rather than round, for a number close to the critical values. E.g., 164.9999 is truncated to 164.9 and fails to make major, rather than being rounded to 165.0 and making major].

Anyway, the inherent precision of the numbers you get for HFs, HHFs, and stage points are limited by the precision of the times going into these calculations. Everyone's TIME is recorded to the nearest 0.01 seconds, an accuracy of +/- 0.005 seconds. That produces an individual HF that is accurate to +/- 0.0050 hit factor units, even though it is reported to a precision of +/- 0.0001. Carrying these numbers into the calculation of Stage Points, we end up dividing 2 hit factors, each with this same accuracy and precision, and multipling by the maximum stage points, which is an integer number of about 30 to 160. The resulting Stage Points of every stage in a match are accurate to about +/- 0.2 stage points, even though they are reported to a precision of +/- 0.0001 points.

Did I mention that Dave S beat Max M by 0.1412 match points, 1767.5842 to 1767.4430 points, for the Production Division win at the Nationals this year? That's less than the statistical accuracy of the match point results for just one stage, and there were 18 stages at the Nationals.

There's a lot to be said for stipulating the margin of difference producing a virtual tie for just such cases.

More digits in the calculations are not going to help. Reporting times to the nearest .001 second would help, if the timers have the capability for that accuracy, and if the ROs can maintain a consistent distance from the competitor at start and end of the stage.

Edited October 17, 2007 by professor

[Alan Meek]

[Flexmoney]

If you go to the USPSA website...click on 'Addtional Content'...then click on 'Classifier Stage Diagrams"...you can then click on the pdf file for any of the classifier stages. The second page of the pdf file has a score sheet...which also serves as a work-sheet for doing the scores by hand.

http://www.uspsa.org/classifiers/index.html

[mactiger]

Not exactly.

For hand calculation--

Hit Factor = Total points shot-penalties (if any) / time. Truncated, not rounded, to 3 decimal places....

Troy

"Not exactly" indeed.

From the "Bible" [current edition of the January 2004 Edition Rule Book]:

9.2.5 Stage results must rank competitors within the relevant Division

in descending order of individual stage points achieved, calculated

to 4 decimal places.

9.2.6 Match results must rank competitors within the relevant Division

in descending order of the combined total of individual stage

points achieved, calculated to 4 decimal places.

So, I guess I missed the 4 decimal places thingy, huh? Was the rest right? Can I get an A-, professor?

I never remember whether it's 3 or 4 decimal places--thanks for the detailed explanation. My head hurts now.

Seriously-very well done.

Troy

[Joe4d]

Figuring by hand,,,,,,,,,,,,,,,,,,,,,,,,,

Step 1 "HAND" your scoresheet to the scorekeeper.

Step 2, Scratch your head and wonder why you keep getting beat by people who miss really quickly.

[AlamoShooter]

Figuring by hand,,,,,,,,,,,,,,,,,,,,,,,,,

Step 1 "HAND" your scoresheet to the scorekeeper.

Step 2, Scratch your head and wonder why you keep getting beat by people who miss really quickly.

now thats funny

[dcarter]

Thats what I want to know. I can figure my stage and match points. What I want to know is, before I shoot, when I should really burn it up or pace myself for the points. I got my _ss handed to me on a couple stages at the Western PA match this year by people who didn't have nearly as good hits on paper. Please don't make my head hurt with the answer. I'm not very good at math. I need to take off my shoes to count to ten.

[Joe4d]

forget all the formulas, day in and day out, a second is worth 10 points, you could do a bunch of figuring and come up with 8.9886446 and then try to deal with that number, or just round it to 10, From what I have seen points really dont matter only thing that matters is time as long as you are hitting paper somewhere.

[Flexmoney]

Joe,

On average, nobody is shooting 10 points per second.

Dan, I did the math for your W.PA match. You averaged a 5.5 hit factor, or 5.5 points per second. That is about one Alpha hit per second. Of course, you can pull the trigger way faster than that. So, where does the time go?

Time is made up on moving through a stage smoothly and efficiently.

[AlamoShooter]

The scoring does seam to have a 10 point per second on the short cours. Like one with 60 points =If your not at 6 seconds and under you dont even have an A class score.

Allso after an ipsc event the other day , that my wife shot as my birthday request.

I got an interesting "point of view" from my her about scoreing. She has shot over 130 matches but just two IPSC events. The prospective was "if Minor scores less on the paper, thin a no shoot should not score the same for Minor as it does fro Major". I guess thats related to match points

And she did not hit any no shoots. She likes the way ICORE scores no shoots.

[get2now]

The scoring does seam to have a 10 point per second on the short cours. Like one with 60 points =If your not at 6 seconds and under you dont even have an A class score.

Allso after an ipsc event the other day , that my wife shot as my birthday request.

I got an interesting "point of view" from my her about scoreing. She has shot over 130 matches but just two IPSC events. The prospective was "if Minor scores less on the paper, thin a no shoot should not score the same for Minor as it does fro Major". I guess thats related to match points

And she did not hit any no shoots. She likes the way ICORE scores no shoots.

I like her thinking... Minor score for penalty targets...

Gary