Online Ratings Progress

[Marcus]

It's been a long time coming, but here is the latest online calculator for your ratings.
http://www.archery-forum.com:16080/maths.lasso

At this point you eneter in your rating, distance, arrows and face size and it spits out your group diviation, arrow average and distance score. This is just the second step to getting the system working the way we have planned.

Thanks to Jim for his help on this one. It's a tough one.

[Eberbachl]

Nice one Marcus and Jim, I just tried it with some made up figures....works great, I'll have to actually find out some real figures to test it with :wink:

[Aarleks]

Works right-on for me. Nice one.

[Juggs]

how do you work out what your rating is

steve

[Marcus]

At this point you kinda have to do it backwards.

Coming up in this project:

Selecting your round or distance shot
Being able to enter your score and getting a rating returned (instead of the other way around)

The first bit is just labour, the second bit requires a fair bit of coding and planning to do.
This project is being done in my spare time so forgive the time it is taking. If anyone has a feature request let me know.

[Marcus]

You can now type in your rating (say 95) and select your round (at this point Mens and Ladies FITAs) and get lets of info. Check it out.

[Kuru]

Cool idea !

[Eberbachl]

That's great, but it seems to give me a score of over 8000 for a Ladies FITA :?

[Marcus]

what rating did you put in?

[Eberbachl]

A rating of 97 gave me a score of a little over 8000 for the Ladies FITA, a rating of 95 gave me a score of just a touch under 8000...

[Marcus]

fixed, put rong info into database. thanx

[Eberbachl]

Cool dude, no problem, is it much work now to add rounds?

[Marcus]

nah just got to do it. should take about 30mins to do. I have to work on the field aspect too!

[Eberbachl]

Yep, cool...It'll be goo dto see probable scores for round right here :D

[DrRalph]

At this point you kinda have to do it backwards.

Coming up in this project:

Selecting your round or distance shot
Being able to enter your score and getting a rating returned (instead of the other way around)



Try this:

http://macnab.anu.edu.au/cgi-bin/rating.pl

Enter your score, select the round and your division and it returns a rating and AA classification. It is only valid up to a rating of 100, so the AIS teams may not be able to use it at the moment.

I can extend it up to a rating of 125 or say 200 :) if anyone really needs it.

DrR

[Marcus]

Thanks. Is this based on a look up table? If so that's not what I'm after (however it is good don't get me wrong). I would love to have it calculate results that are not in the lookup table.

However I will bookmark this one as it is very very handy, thanks

[DrRalph]

Thanks. Is this based on a look up table? If so that's not what I'm after (however it is good don't get me wrong). I would love to have it calculate results that are not in the lookup table.

However I will bookmark this one as it is very very handy, thanks

Oh I see, you are right. But I do use an excel spreadsheet that implements the AA ratings formulae to make the lookup tables, which is how I would extend the tables to any rating you want. The XL sheet works for arbitrary arrows, target face and distances.

With a bit of work the tables could be generated on the fly for arbitrary targets and distances. I have even used the spreadsheet to make up tables for rounds like the York and Philladelphia with their 9,7,5,3,1 scoring.

I figured a lookup table was sufficient for people shooting standard rounds. You are right though, it would be cool to be able to enter say a score for 72 arrows at 70m on an 60cm face (our in-house Adaminaby round!) and get an AA rating. It could give new round experimenters a way to guage things. How about a 110, 90, 70, 50m super FITA for compound archers?

Cheers
DrR

[Flehrad]

So what does group deviation actually mean?
Is it the deviation distance from the center X to the furtherst arrow?...
In mm?....

Cos my rating of 79 (for a pratice Sht Canberra I did today) was really accurate (within 2 points - scored 841, calculated 839).
But it had 77, 59 and 42 listed in deviation.

So my arrows were 77mm deviated at 50, 59mm deviated at 40 and 42mm deviated at 30?......

[DrRalph]

From looking at the AA rating calculations, I think they are in mm, and they are the radius of the circle that you can expect about 2/3 of your arrows to land, ie +/- 1 standard deviation on a normal curve.

ie, a deviation of 50mm radius says about 2/3 of your arrows landed inside a circle 10cm in diameter, smaller than the 12cm 10 circle.

Did you break any arrows? :-?

[Flehrad]

Not that time.
Because I had pins!!!
Yay.
It's the second time that my vector pins on my triples have saved a shaft because Aarleks smacked one of my shafts good down the center at 30m and left the pin slightly bent and a nifty groove down it.
Just stuck on another pin nock, good as new (the slight bend didn't effect the nock going on, or how it shot because it still grouped the same, at least at 50m with my shooting :lol: )

42mm at 30m deviation. I'm happy with that. :D

[Marcus]

Dr Ralph
Can you set your program up to go to 120 perhaps? A rating of 100 isn't very high and it would be good to know how far over some can get.
Is that difficult?

thanks

[James Park]

The AA formulae are all in mm.
The "Standard Deviation" is the Standard Deviation of the Normal distribution used in the modelling. As noted, it is the radius (in mm) of the circle from the centre of the group within which about 2/3 of your arrows will hit.
Using the AA formulae, you can go directly from a rating to a score for any face size, scoring system, distance, etc., quite easily.
The more difficult calculation is to go from a score to a rating, which is what my Visual Basic program does. Generally, this is the more useful direction to have the calculation, but it is not easy to do because the equations are too difficult (at least for me) to invert. Hence, my program does it by iteration. Having programmed it, I can deal with ratings from 0 to infinity, and am not stuck with integer ratings but can do fractions as well (eg rating = 107.35).

[James Park]

Another thing worth bearing in mind is that the diameter of the arrow is allowed for in the AA formulae so that you can deal with line-cutters properly.
However, when we first created the formulae (back in the early 1970's), everyone was using X7 aluminium arrows, so we included an average arrow diameter of 7 mm, which is too large for today's target archery, and too small for today's indoor archery.
Hence, in my program I have that size as a default, but let the archer enter a different size if he wishes so that he can evaluate the benefit of large arrows (for indoor) or the penalty of skinny ones (for example).

[DrRalph]

Dr Ralph
Can you set your program up to go to 120 perhaps? A rating of 100 isn't very high and it would be good to know how far over some can get.
Is that difficult?

thanks

Sure, That Korean shot a rating of 117 with his 337 at 90m, and you compound shooters can even exceed that.

I'll run the tables up to a 155 or so rating and let you know when it is done.

I can also put in the indoor rounds.

I'll have a go at it in the coming weeks, I'll be a bit snowed under with work after my July conference.

[DrRalph]

While I have not finished extending the tables above 100 Ratings, for you elite types out there :) Here are my calculations for the main FITA rounds up to perfect 1440 scores, from where the AA rules leave off...

Rtg MFITA WFITA
155 1440 1440
154 1440 1440
153 1439 1440
152 1439 1440
151 1439 1440
150 1439 1440
149 1439 1440
148 1438 1440
147 1438 1440
146 1438 1440
145 1437 1440
144 1437 1440
143 1436 1439
142 1436 1439
141 1435 1439
140 1434 1439
139 1434 1438
138 1433 1438
137 1432 1438
136 1431 1437
135 1430 1437
134 1428 1436
133 1427 1435
132 1426 1434
131 1424 1434
130 1423 1433
129 1421 1431
128 1419 1430
127 1417 1429
126 1415 1428
125 1413 1426
124 1411 1424
123 1409 1423
122 1407 1421
121 1404 1419
120 1402 1417
119 1399 1415
118 1396 1413
117 1393 1410
116 1390 1408
115 1387 1406
114 1384 1403
113 1381 1400
112 1377 1397
111 1374 1394
110 1370 1391
109 1366 1388
108 1362 1385
107 1358 1381
106 1354 1378
105 1350 1374
104 1345 1370
103 1341 1366
102 1336 1362
101 1331 1358
100 1326 1354

[DrRalph]

Folks,

The ratings lookup for a round score page at:

http://macnab.anu.edu.au/cgi-bin/rating.pl

has been updated to include indoor round (with inner 10s as well) and all the rounds are now rated up to perfect scores and hence maximum ratings possible. For example a perfect 180 score for a 18 arrow 70m matchplay would need a rating of 138!

Now all you 100+ rating recurvers and compund archers can compare performances in different rounds. ie is a 593 inner 10 FITA-1 better than a 716 FITA 70m round? :fadein:

I hope one day to be able to make use of this extension!

[Clare Barnes]

While I have not finished extending the tables above 100 Ratings, for you elite types out there :) Here are my calculations for the main FITA rounds up to perfect 1440 scores, from where the AA rules leave off...

The AA Rule Book actually goes up to a 125 rating for most rounds, on page 21 of Chapter 4 for FITAs and various other pages for other rounds. :-?

[DrRalph]

Oh yes, sorry Clare. I pasted too much above :oops: AA does give up to 125 for the FITAs. (plus a select few other rounds, field rounds and the Indoor FITA rounds)

My online one used to stop at 100, and I was upgrading it for Marcus. Now I've taken all the target and indoor rounds on the web page up to perfect scores in each round. Should last a while I hope.

[CMB50]

Marcus,

I can't get your link to work. Is it still current?

[DrRalph]

See also my new palm pilot app, (thread in target and indoor). :)

[CMB50]

I had a quick look at it, but don't have a palm pilot. :(

[Marcus]

http://www2.archery-forum.com/maths.lasso

should work

[CMB50]

Yep, works fine.

Thanks. :D

[Marianne Rieckmann]

Using the AA formulae, you can go directly from a rating to a score for any face size, scoring system, distance, etc., quite easily.
The more difficult calculation is to go from a score to a rating, which is what my Visual Basic program does. Generally, this is the more useful direction to have the calculation, but it is not easy to do because the equations are too difficult (at least for me) to invert. Hence, my program does it by iteration.
I have been looking at the original turbo pascal code ( I think it was written by Malcolm Kay back in 1985). I understand it goes from rating to score, generating the AA tables that we all use.
I have come up with the same problem, in trying to do a direct calculation from score to rating... trying to invert the equations... not much progress yet.

Has anyone made any progress with this equation ? Is it possible ?

[James Park]

Marianne,
It is a complicated non-linear equation and a major problem to invert. I do not expect anyone to be able to invert it. Much easier to just do it by iteration as I have done.

[Marianne Rieckmann]

Ok, thanks Jim.
I will not waste the time trying to invert. Just do some sort of iteration, a B tree lookup maybe...
Thanks again,
Marianne