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Sportz
6th January 2005, 08:22 PM
Dr Ron,

Okay, this is the pricing method I was talking about. You might like to experiment with it a bit and see if it works for you.

You'll notice that it heavily favours horses near the top of the ratings (that's the way Don Scott used to do it) and doesn't even consider horses rated over 10 kgs behind the top rated horse. Well, if a horse is rated that far behind, you really shouldn't worry about it any way.

Firstly, you convert your weight ratings to a score out of 100 using this table I've made:

Top rated horse = 100 points
0.5 kgs behind = 85 points
1.0 kgs behind = 70 points
1.5 kgs behind = 60 points
2.0 kgs behind = 50 points
2.5 kgs behind = 44 points
3.0 kgs behind = 38 points
3.5 kgs behind = 33 points
4.0 kgs behind = 28 points
4.5 kgs behind = 24 points
5.0 kgs behind = 20 points
5.5 kgs behind = 17 points
6.0 kgs behind = 14 points
6.5 kgs behind = 12 points
7.0 kgs behind = 10 points
7.5 kgs behind = 8 points
8.0 kgs behind = 6 points
8.5 kgs behind = 4 points
9.0 kgs behind = 3 points
9.5 kgs behind = 2 points
10.0 kgs behind = 1 point
10.5+ kgs behind = 0 points

Here's an example race to show you:
No.1 - Rtg 59.0 = 100 points
No.2 - Rtg 57.0 = 50 points
No.3 - Rtg 56.0 = 38 points
No.4 - Rtg 54.0 = 20 points
No.5 - Rtg 53.5 = 17 points
No.6 - Rtg 56.5 = 44 points
No.7 - Rtg 52.5 = 12 points
No.8 - Rtg 50.5 = 4 points

Then you simply add up the scores of all the horses in the race to get a total. To get each horse's price you simply divide that total by each horse's score. In this case, the total of all the scores is 285, so you simply divide 285 by all the horses' scores, do a little rounding up or down and you get the following approximate dividends:

No.1 - $2.85
No.2 - $5.70
No.3 - $7.50
No.4 - $14.25
No.5 - $16.75
No.6 - $6.50
No.7 - $23.75
No.8 - $71.25

That is of course a 100% market. If you want to get a market which more accurately compares with TAB prices, you should actually multiply the total score of 285 by .85 and then divide that figure by each horse's score.

That's it. All you need is that points table and a calculator and it doesn't take long at all.

DR RON
6th January 2005, 08:29 PM
Thanks Sportz

Sportz
23rd February 2005, 02:31 PM
Ron,

I'm not sure if you were using my pricing method, but I know you recently said that you were having problems with getting accurate prices for your ratings. Well, I've been having similar troubles. I've found that with my new ratings I'm using, my top rated horses are coming up a bit too short. So I've had a bit of a tinker around and come up with a new 'Ratings to prices' table. Feel free to have a go at this:

Top rated horse = 100 points
0.5 kgs behind = 90 points
1.0 kgs behind = 80 points
1.5 kgs behind = 72 points
2.0 kgs behind = 64 points
2.5 kgs behind = 57 points
3.0 kgs behind = 50 points
3.5 kgs behind = 45 points
4.0 kgs behind = 40 points
4.5 kgs behind = 36 points
5.0 kgs behind = 32 points
5.5 kgs behind = 28 points
6.0 kgs behind = 24 points
6.5 kgs behind = 21 points
7.0 kgs behind = 18 points
7.5 kgs behind = 16 points
8.0 kgs behind = 14 points
8.5 kgs behind = 12 points
9.0 kgs behind = 10 points
9.5 kgs behind = 9 points
10+ kgs behind = 8 points
11+ kgs behind = 7 points
12+ kgs behind = 6 points
13+ kgs behind = 5 points
14+ kgs behind = 4 points
16+ kgs behind = 3 points
18+ kgs behind = 2 points
20+ kgs behind = 1 point

DR RON
23rd February 2005, 03:40 PM
Actually sportz, the problem was that the prices for my favoured ones seemed to come up a bit longer than I woulde xpect in reallity. But maybe I was not generous enough with some of my ratings, Will experiment with your updated table. thanks

Sportz
23rd February 2005, 04:03 PM
Oh okay. Well, not sure my revised table would be much good then. It would tend to slightly lengthen the price of favourites and shorten the prices of the roughies.

crash
23rd February 2005, 04:15 PM
Am I missing something here, or wouldn't you end up with a few groups all with the same price ? Going no further would be OK for 2 and 3yr. olds where a min. horse profile exists but beyond that age range the prices would become misleading.

I often use a similar method to get an initial [base] rating figure and then divide each runner's number into the total to obtain a probability as you both have done, but then I divide SR by 3 [add a 0 to SR] and adjust up or down according to good or bad stats [+10 for a win at the track or a -10 for no wins etc. as an example] and finally add this to the initial base rating and convert to price.

PS. I use a 1 to 10 method for my base rating without adding a 0 to the SR and use +1 or -1 for stats but I've worked it above to fit your methodology.

Try it out.

Sportz
23rd February 2005, 04:49 PM
Sorry Crash. I'm not sure I understand what you're talking about.

This thread is all about how to convert your final ratings to a price, not how you get your ratings in the first place. The table I've posted here is for use on Weight ratings, hence the reference to 'kgs behind'.

crash
23rd February 2005, 05:11 PM
Oh, Sorry Sports I see what you are doing now.

Sportz
26th February 2005, 09:28 AM
Speaking of converting Ratings to prices, there's a new Ratings price converter on the Puntmaster website.

Sportz
12th March 2005, 02:41 PM
Okay, well I've gone from having the top rated runners a bit too short to having them a bit too long, so I've made another slight adjustment to the table and I think I've probably got it just about right now.

Top rated horse = 100 points
0.5 kgs behind = 87 points
1.0 kgs behind = 75 points
1.5 kgs behind = 65 points
2.0 kgs behind = 57 points
2.5 kgs behind = 50 points
3.0 kgs behind = 45 points
3.5 kgs behind = 40 points
4.0 kgs behind = 36 points
4.5 kgs behind = 32 points
5.0 kgs behind = 28 points
5.5 kgs behind = 24 points
6.0 kgs behind = 20 points
6.5 kgs behind = 17 points
7.0 kgs behind = 14 points
7.5 kgs behind = 12 points
8.0 kgs behind = 10 points
8.5 kgs behind = 9 points
9.0 kgs behind = 8 points
9.5 kgs behind = 7 points
10+ kgs behind = 6 points
11+ kgs behind = 5 points
12+ kgs behind = 4 points
13+ kgs behind = 3 points
15+ kgs behind = 2 points
20+ kgs behind = 1 point