(GRL10) HORSE RACING RATINGS: Back And Lay To A +538 Unit Profit

Information That's Not Generally Available Will Make You Profitable

Michael WildingAugust 3, 2020

8 1,234 7 minutes read

Horse racing ratings are an integral part of finding a profit from betting on the horses.

With more ratings for every horse than any other provider in the UK, we began a public analysis of each one in 2020, and are adding to them regularly.

You can see all the ratings in the series here.

Some will perform well and make insane horse racing profits on their own, others will not perform as well, but will indicate strong horses, and work excellently when combined with other factors.

In this post, we’re going to look at the GRL10 rating. This information is likely to be taken into account by the markets, as looking at past finish positions is going to give an idea of how good each horse’s last race was. However, how much it’s been taken into account, and whether there’s an advantage we can find in it, is what we’re going to investigate today.

What is this information?

It’s the number of Good Races in last 10 races.

It tells us how a horse has been performing in its most recent runs, and it allows us to compare this directly to the other runners in the race, to see if it’s been performing better or worse.

We also have rankings (Rnk) and difference from top (DiffTp) versions of this rating as well.

Before we dig in and see how it performs, let’s see…

WHAT HORSE RACING RATINGS’ STATS MEAN

We use a few pieces of information that help us to understand the performance of horse race ratings. Below you will find an explanation of these for reference.

SELECTIONS

The number of selections that have been found.

PROFIT

The profit, or loss, of the selections to Betfair SP with a 2% commission. Where Betfair SP isn’t available, we have used the SP odds.

WINS

The number of winners found in this sample of selections.

STRIKE RATE

The percentage of winners found from the selections.

ROI

Return On Investment. The percentage return made on turnover, based on betting 1 unit per selection.

A/E

Actual/Expected. Also known as the PIV (Pool Impact Value). This shows how many winners were found, compared to the number of expected winners (based on odds). If this figure is greater than 1, then we have an edge, less than 1 and we don’t!

CHI2

The chi square is a statistical test, which tells us how likely the results are due to chance or skill. 100% means the results are 100% based on chance, we want these to be as low as possible.

DOES THE GRL10 RATING MAKE HORSE RACING PROFITS?

Using data from 2018 to the present day, I’m going to start by breaking the ratings down into some relevant groups. Each of these groups has been designed to have roughly the same amount of runners.

GRL10 RAW PERFORMANCE

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	70932	-32.67	3940	6%	-0.05%	1.01	0.60
1	39230	-23.92	4463	11%	-0.06%	1.01	0.50
2	37792	-5.90	4470	12%	-0.02%	1.01	0.33
3	37769	-46.09	4394	12%	-0.12%	1.01	0.72
4	34236	-144.11	4049	12%	-0.42%	0.98	0.18
5	28600	-130.75	3517	12%	-0.46%	0.98	0.17
6	19721	-59.61	2599	13%	-0.30%	0.99	0.67
7	11283	-87.99	1528	14%	-0.78%	0.96	0.08
8	4838	-47.52	713	15%	-0.98%	0.95	0.14
9	1519	-19.07	244	16%	-1.26%	0.94	0.29
10	342	17.56	102	30%	5.13%	1.23	0.02

In terms of raw performance, we see a steadying increase in strike rate as a horse has more good races out of the ten, with a horse that has had a good race in all ten of its last runs winning over 29% of its races.

Interestingly, there’s a decrease in ROI the more good races a horse has had, which indicates that the market is well aware of this, and has taken it into account in the odds. Something that we would expect. The A/E confirms this picture.

However, horses that have had ten out of ten good races seem to be significantly under-valued by the market. The market expects them to win only 24% of the time, instead of over 29% of the time, and this has produced a small profit since 2018, with a whopping advantage of 23%!

It may also be worth investigating whether there’s any advantage in laying horses who have had between seven and nine good races in their last ten.

WE NEED MORE INFORMATION!

Based on the initial analysis, we know that this factor is going to require more information to be of any use to us.

We could look at a form rating, but GRL10 is already form based, so instead we’ll look at a speed rating.

I am going to choose the rank for SPDFIGLrAdj, since we’ve already investigated this rating here. You could use any other rating if you preferred, this is an example of what can be done with a single extra factor.

Here’s what we find…

RANK 1: SPDFIGLrAdj

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	20446	15.50	1366	7%	0.08%	1.03	0.28
1	4180	-1.84	603	14%	-0.04%	1.01	0.77
2	3814	96.21	714	19%	2.52%	1.17	0.00
3	4006	44.21	698	17%	1.10%	1.08	0.02
4	3717	11.18	663	18%	0.30%	1.03	0.38
5	3158	35.82	612	19%	1.13%	1.08	0.04
6	2348	22.12	463	20%	0.94%	1.07	0.13
7	1455	-9.06	286	20%	-0.62%	0.98	0.74
8	622	-3.47	132	21%	-0.56%	0.99	0.87
9	228	3.22	56	25%	1.41%	1.08	0.53
10	61	2.26	22	36%	3.71%	1.13	0.50

Of course, there’s a huge reduction in the number of selections, and we still see that increase in strike rate the more good races a horse has had. In fact, it’s now as high as 36% for horses that have had ten good runs in the last ten races, and are top ranked for SPDFIGLrAdj.

The downside… there has only been 61 selections since 2018, which is less than 2 selections per month, for a low return on investment.

However, we’re now starting to see an advantage in the middle of the range of GRL10 ratings

Horses that are ranked first for SPDFIGLrAdj and have had between two and six good runs out of their last ten races, have not only made a profit of +209.54 units, but have an average advantage of 1.09 (or 9%). This is pretty good, although the ROI is still low. But, with an average of 18 selections a day, there’s still plenty of scope to refine this further.

RANK 2: SPDFIGLrAdj

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	6081	21.10	416	7%	0.35%	1.07	0.15
1	3074	-7.11	412	13%	-0.23%	1.00	0.95
2	3426	17.01	549	16%	0.50%	1.05	0.24
3	3843	18.19	612	16%	0.47%	1.05	0.22
4	3519	26.05	583	17%	0.74%	1.06	0.11
5	3026	-5.51	497	16%	-0.18%	1.00	0.93
6	2175	46.11	414	19%	2.12%	1.14	0.00
7	1365	-1.56	242	18%	-0.11%	1.01	0.89
8	638	11.97	138	22%	1.88%	1.11	0.16
9	183	-5.92	34	19%	-3.23%	0.86	0.33
10	61	4.91	24	39%	8.05%	1.28	0.15

All the GRL10 horses scoring 2 to 6 have made a profit again, with the exception of horses having 5 good runs in the last ten. However the strike rates and A/E ratios have dropped.

HOW DO DIFFERENT RACE TYPES AFFECT THIS RATING?

The following tables show the different performance of GRL10 ratings, where the SPDFIGLrAdj is top ranked.

NH FLAT

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	1389	-1.76	143	10%	-0.13%	1.00	0.97
1	397	-3.56	86	22%	-0.90%	0.97	0.77
2	119	4.74	37	31%	3.99%	1.16	0.28
3	33	-2.30	6	18%	-6.98%	0.73	0.37
4	13	2.46	6	46%	18.93%	1.73	0.11
5	8	-1.22	0	0%	-15.29%	0.00	0.23
6	1	0.62	1	100%	62.39%	2.75	0.19
7	1	-0.33	0	0%	-32.79%	0.00	0.48
8	1	-0.09	0	0%	-9.09%	0.00	0.75
9	0	0.00	0	0%	0.00%	0.00	0.00
10	1	-0.39	0	0%	-39.48%	0.00	0.42

CHASE TURF

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	119	1.80	12	10%	1.52%	1.20	0.51
1	273	8.99	43	16%	3.29%	1.29	0.07
2	443	32.83	100	23%	7.41%	1.52	0.00
3	631	29.59	135	21%	4.69%	1.31	0.00
4	726	6.58	147	20%	0.91%	1.06	0.42
5	746	8.58	157	21%	1.15%	1.07	0.32
6	558	9.88	134	24%	1.77%	1.09	0.24
7	351	-1.40	87	25%	-0.40%	1.00	0.97
8	135	-0.31	34	25%	-0.23%	1.00	0.98
9	59	8.30	26	44%	14.07%	1.50	0.01
10	14	1.85	7	50%	13.23%	1.38	0.29

FLAT TURF

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	12523	-7.89	776	6%	-0.06%	1.01	0.85
1	1676	4.77	234	14%	0.28%	1.04	0.56
2	1406	14.01	215	15%	1.00%	1.09	0.19
3	1467	-0.78	206	14%	-0.05%	1.01	0.87
4	1291	8.24	204	16%	0.64%	1.06	0.38
5	1045	-4.82	159	15%	-0.46%	0.98	0.83
6	803	5.18	134	17%	0.64%	1.06	0.49
7	533	-1.41	91	17%	-0.26%	1.00	0.99
8	238	-2.57	41	17%	-1.08%	0.95	0.74
9	96	-1.56	17	18%	-1.63%	0.93	0.73
10	26	0.98	9	35%	3.77%	1.14	0.65

HURDLE TURF

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	787	10.46	73	9%	1.33%	1.19	0.12
1	986	-5.46	152	15%	-0.55%	0.98	0.77
2	1071	27.47	239	22%	2.56%	1.15	0.02
3	1050	14.75	230	22%	1.40%	1.08	0.18
4	935	16.51	220	24%	1.77%	1.10	0.12
5	736	27.88	187	25%	3.79%	1.19	0.01
6	519	-0.83	107	21%	-0.16%	1.01	0.95
7	269	-5.07	54	20%	-1.89%	0.92	0.51
8	113	-2.29	28	25%	-2.03%	0.93	0.67
9	29	-3.32	5	17%	-11.43%	0.61	0.18
10	10	0.03	4	40%	0.26%	1.01	0.97

HUNTER CHASE

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	13	2.92	5	38%	22.49%	2.51	0.02
1	23	-0.57	2	9%	-2.50%	0.79	0.72
2	21	0.99	5	24%	4.69%	1.26	0.56
3	32	3.26	9	28%	10.20%	1.60	0.12
4	31	2.93	11	35%	9.45%	1.38	0.21
5	27	0.54	9	33%	2.00%	1.08	0.79
6	16	2.35	7	44%	14.66%	1.53	0.18
7	9	-0.91	2	22%	-10.15%	0.69	0.52
8	4	-0.51	1	25%	-12.85%	0.67	0.60
9	1	0.80	1	100%	80.02%	5.45	0.03
10	0	0.00	0	0%	0.00%	0.00	0.00

ALL WEATHER FLAT

GRL10	Selections	Profit	Wins	Strike Rate	ROI	A/E	Chi2
0	5572	11.46	354	6%	0.21%	1.05	0.33
1	818	-5.41	86	11%	-0.66%	0.95	0.64
2	752	16.29	118	16%	2.17%	1.18	0.05
3	790	-0.87	110	14%	-0.11%	1.01	0.94
4	716	-25.23	74	10%	-3.52%	0.75	0.01
5	595	5.20	100	17%	0.87%	1.07	0.46
6	449	4.21	79	18%	0.94%	1.07	0.50
7	290	-0.05	51	18%	-0.02%	1.01	0.91
8	130	2.72	28	22%	2.09%	1.12	0.49
9	42	-0.93	7	17%	-2.22%	0.89	0.74
10	10	-0.20	2	20%	-2.05%	0.92	0.89

More than anything else, this gives us an insight into the dynamics of different race types, and how many horses have had different numbers of good races in their last ten.

For example, any horse racing in a Chase Turf race that has had nine or ten good races in their last ten runs should be taken very seriously. We can’t make much profit focusing on them alone, but if you see one of them running, then you know they don’t appear often, and when they do, they win a huge number of the races they’re in.

Chase Turf races also produce the best overall results, but the volume of selections is low. If you like micro-systems, then there’s a number to be had here, but it isn’t for me, and I wouldn’t break this down by race type.

WHAT ABOUT LAYING HORSES?

Let’s not forget, we had some strong possible lay bet selections in horses who had between 7 and 9 good runs in their last ten races. The logic being, that the market had adjusted for this, but the odds have over-compensated and are now too low.

Just calculating the profit on these runners, laying at Betfair SP with a 2% commission, a whopping profit of +262 units profit would have been made since 2018.

This could have been further increased to +374 units profit, by removing the top four ranked SPDFIGLrAdj horses, and still getting an average of two selections a day.

IN SUMMARY

The GRL10 rating is a rating, which allows us to easily see how well a horse has performed in its last ten races. This information is available in a horse’s form, by looking at each runner’s past performance, and seeing the position it finishes in, and the distance from the winner.

This means the market has taken account of it.

However, we found that by combining this information with horses that were top ranked for SPDFIGLrAdj, a profit of +209 units could be made for horses that have had between two and six good runs out of their last ten.

There was a big advantage of 9% in these runners, but they had a low ROI of 1.23%.

We then investigated different race types, but found very little of interest outside of Chase Turf race, which had comparatively small numbers of selections.

Finally, we looked at the possibility of laying horses who had between seven and nine good races in their last ten. This was done on seeing that these runners had a low advantage, most likely due to the market being aware that they were strong runners, and the odds reducing more than they should.

These runners made a profit to lay bets, and that profit was increased by limiting the odds to 15.00 or less.

We then increased this profit even further, by only focusing on those selections which were also ranked worse than fourth for the SPDFIGLrAdj, and we got a final profit of +374 units.

These selections have a strike rate of 86% across an average of two selections a day, with a return on investment of 2.66% per bet.

That’s a total of +583 units profit since 2018.

We got these results by:

Finding back-to-win selections with two to six for GRL10 and are ranked 1 for SPDFIGLrAdj
Find lay selections that have Betfair SP odds of no more than 15.00, have seven to nine GRL10 and are ranked 5th or worse for SPDFIGLrAdj

You could take this further by researching how this rating performs under different race conditions, or alongside other ratings.

Let me know if you consider how many good races a horse has had in its last ten runs, by leaving a comment below.

The GRL10 and SPDFIGLrAdj horse racing ratings are available to RA Pro members on the Standard race card. In only a few seconds you can create a custom race card with the ranking version of this horse racing rating on it.

If you’re not yet a member of RA Pro, you can register here.

You can practice this approach, and develop it further for zero-risk, at Aldermist, the world’s only LikeReal Racing platform. Any system or strategy that is profitable at Aldermist will also be profitable on live racing.