Chester Draw & Pace Bias: Part 2
This is a follow up article to the Chester piece I wrote in April, writes Dave Renham. In that article I concentrated on sprints of between five and seven furlongs; here I am will look in detail at the extended 7f trip and the 1m 2f distance.
As I am writing this (on May 4th), I feel sad because this week would have signalled the Chester May Meeting which is one of my favourite meetings of the year. The signs are, however, that racing may be back quite soon with Germany and France hopefully set to start again in the near future. When it resumes here, racing will be behind closed doors but for everyone involved in the sport I am sure they will just be glad to get going again.
Since writing the first three articles in this draw/pace series there has been a useful addition to the Draw and Pace Analyser tools whereby you can now narrow down your query by year range. In the past it showed all years going back to 2009 and in order to look at more recent data I needed to use the Query Tool as well. This speeds my draw and pace research up especially when wanting to research time sensitive data.
What the new addition also means is that I can look at the data in a slightly different way using a method I first saw in Nick Mordin’s excellent book, ‘Winning Without Thinking’. He looked at data in five-year batches which is a good way to try and compare things more effectively. This method also potentially highlights whether patterns or biases are changing, and offers more reliable sample sizes.
Below is an example of this method based on 7f handicap data from Goodwood, which I hope illustrates his idea neatly. Back in the late 1990s and early 2000s Goodwood’s 7f trip provided me with plenty of winning bets, many of them forecasts and exactas on horses drawn closest to the rail; but the officials got wise to the bias and managed to even it out a little for some years. However, back in 2015 or so I started to notice that the low draw bias was beginning to reappear.
Here is a table using five-year batches of data with percentages for each third of the draw as well as A/E values. The full 11-year data is shown at the top of the table for long term comparison:
I have highlighted in green the low draw data which shows a big change from the first five years (2009-2013) in terms of the low draw bias gradually getting stronger. Having said that I know that 2018 and 2019 have both seemingly started to show a decline again in the strength of bias - this is just beginning to be shown in the 2015-2019 data. The next couple of years may well determine whether Goodwood are increasing efforts once again to level out the ‘draw playing field’. Hence I really think splitting year data in this way is a useful tool for comparisons and I will aim to use it in articles where it is appropriate.
So time to delve back into Chester’s stats. As before I am using some of the tools available on the Geegeez website, those being the Draw Analyser, the Pace Analyser and the Query Tool. The main period of study goes back to 2009, but as before I will examine a more recent data set (2015 to 2019) in detail, too, where appropriate, as well as using the new 5-year comparison method.
I will be focusing once again on 8+ runner handicap races and, as stated in the first paragraph, looking mainly at the extended 7f trip and 1m2f. The draw will be divided into three equal sections or thirds (low, middle, high) and non-runners have been taken into account with draw positions adjusted accordingly. The pace data is split into four groups: led, prominent, mid division and held up.
Chester 7 1/2 furlongs (8+ runner handicaps)
When analysing this trip on Geegeez Draw Analyser you need to look at the 1 mile distance to get this extended 7f data. Otherwise if you key in 7 furlongs you will get the 7f data from the last article. This is because the actual distance is 7f 127 yards, which is closer to a mile than seven furlongs.
Since 2009 there have been 115 races that have qualified which is a decent sample. Here are the 11 season overall draw splits:
There appears to be a slight edge towards lower draws but, compared with the 5 – 7f data, we can see that this 7½f distance offers low draws far less of an advantage.
The A/E values are shown below for this period:
A fairly even playing field here so, despite the small low draw edge in terms of percentage wins, it looks like the bookmakers have that well factored into their prices.
It is time now to look at each draw position broken down by individual stall number:
Perhaps no real surprises here given the draw thirds data. There does seem to be something to be gleaned from looking at the each way placed percentages: combining the figures for horses drawn 10 or wider they have made the frame (i.e. won or placed) just 16% of the time. Their combined win A/E value is also low at 0.55. Compare this with horses drawn 1 to 9 who have placed 30% of the time with an A/E value of 0.88. It seems the long term data suggests that horses drawn 10 and above are at a fairly significant disadvantage to those drawn lower.
Onto a more recent data set looking at the past five seasons (2015-2019). Here are the draw splits for the 58 races that have occurred during this time frame.
This tells a similar tale to the ’09-’19 figures but with a slight increase in the low draw win percentage. This small increase is not statistically significant and the A/E values again indicate a relatively level playing field in terms of potential profitability as shown below:
The five-year stats for individual draw positions are below:
Again it is only the each way percentages that catch my eye, mirroring the long term data (draws 1 to 9 with 32% of placed runners; draws 10 and above with 11.4% of placed runners).
Let us break down the draw figures using rolling five-year batches to compare the data in another way:
Looking at the table we can see that the low draw bias has been very consistent from 2011 onwards and it seems that in 2009 and 2010 for whatever reason low draws slightly under-performed.
Ultimately this is a course and distance where there is a slight low draw edge and, as indicated earlier, draws 10 and above look to be at a fairly significant disadvantage. Hence it should not come as a surprise that as the field size grows the bias towards low draws increases as does the bias AGAINST higher draws. Here are the data for fields with 12 or more runners for 2009 – 2019 (44 races in total):
In bigger fields I would be very wary of backing anything drawn high unless I felt the horse had a huge edge over the rest of the runners, or that its price more than justified the risk. The A/E values correlate neatly as we can see:
It looks therefore that we have a potentially playable draw bias when we get to 12+ runners. Indeed the bias does seem to strengthen when we increase the field size further, but of course the number of races becomes smaller and less reliable from a statistical point of view.
In the first Chester article I pointed out how exotic bets (forecasts, exactas, etc) over 5f would have proved profitable under certain circumstances. Once again I have delved into this area for this distance when the field size has been 12 or more. There are some interesting ideas that would have proved highly profitable during the period of study for these bigger field races:
a) perming the bottom four draws in 12 x £1 straight forecasts would have seen an outlay of £528 and produced returns of £627.49 meaning of profit of £99.49. The exacta paid more (potentially increasing profit by a further £130 to be precise), but exactas being pool bets are not always a good vehicle for draw-based bets: they can easily be ‘overplayed’ and the dividend suffers as a result;
b) perming the five lowest draws in 60 x £1 tricasts would have seen a significant outlay of £2640 but produced huge returns of £4845 meaning a healthy profit of £2205, and an ROI of 84%.
Of course, past profitable results are simply that – past results. However, I have made most of my profits over the years using these exotic bets on draw biased races and the profits quoted are not unusual.
Let us look at pace and running styles now. The overall figures (2009-19) are thus:
A very even playing field here, although hold up horses seem at a slight disadvantage.
I have checked ground conditions and there is nothing clear cut; however, field size does seem to make a difference as it did with the draw. If we look at 12+ runner races again we get the following pace results:
In bigger fields front runners have the best record and have an edge; meanwhile, hold up horses seem to really struggle.
Now a look at draw / pace (running style) combinations for front runners in these 7½f races. Remember this is looking at which third of the draw is responsible for the early leader of the race (in % terms):
Lower draws are more likely to take the early lead but with a run of around 1½ furlongs to the first bend horses drawn wider find it easier to contest for the lead should they wish too. What is noteworthy is that early leaders from low draws go on to win a far bigger percentage of races than those who led drawn in the middle or out wide (high). 58 horses have led from low draws with ten going onto to win the race (17.2%); 81 horses have led from middle or high draws with only six managing to go on to win (7.4%). It should also be noted that prominent runners from a low draw have a decent record, scoring more 15% of the time.
In conclusion, lower draws do have an edge but it is only when we get to bigger fields (12+) that the bias looks playable. Not only do bigger fields increase the edge for low draws, they decrease the chances of high drawn horses. Pace wise the only bias seems again to occur in bigger fields where front runners have an advantage while hold up horses find it very difficult to win.
Chester 1 mile 2 1/2 furlongs (8+ runner handicaps)
There were 94 qualifying races at this distance from 2009 to 2019. The 1m 2f 70 yards distance has been shortened by 5 yards since 2009, not that that would make any difference. Here are the draw splits:
Low draws definitely have had an edge over the 11 seasons, while there seems little in it between middle and higher draws. Let’s look at the A/E values to see whether this bias is appreciated by bookmakers:
No real edge it seems from a punting perspective with an extremely level set of A/E values. Let’s see what the individual draw positions offer:
The lowest six draws seems the natural cut off point in terms of win strike rate, and the A/E values for draws 1 2, 5 and 6 are decent. However, only draw 5 has made a ‘blind’ profit.
Look at the going data there have only been 20 races on good to firm or firmer, but my impression is that any low draw bias is less potent under such conditions. The win percentages are more even and the win and placed figures see just 2 more placed efforts for low draws compared with high. Such a small number of races means it is simply a hypothesis, however.
Onto the last five seasons now. There have been 43 qualifying races since 2015, with the draw splits as follows:
A more even set of figures in the more recent past with low draws only marginally best in win percentage terms. And the A/E values:
Low draws have proved to be poor value over the past five seasons despite still winning more races. The individual draw figures for 2015 to 2019 look like this:
Draws 1 and 2 have a really poor record in the more recent past and checking back from 2009 to 2014 both stall positions actually made a blind profit. This illustrates how religiously backing individual draw positions can be a real roller coaster and in general too risky long term.
Let us now look at the draw figures for 1m 2f using the five-year comparison method discussed earlier:
The five year batch data seem to back up what the 2015 to 2019 figures had suggested: that the low draw bias has been gradually diminishing. I am not sure why this has been happening – it may just be down to chance and it will be interesting to see what results the next couple of seasons bring.
A look pace and running styles now. Here are the overall figures going back to 2009:
These figures show that front runners have a significant edge which, considering the distance, is unusual. In general in flat races, the longer the distance the less successful front runners are. But Chester's very tight, always on the turn, configuration does make it harder for horses to pass without travelling further and using up more fuel.
A win percentage for front runners of nearly 20% really caught my eye. To illustrate this pace bias more clearly, the average win percentage all UK courses over the 1m 2f distance (8+ runner handicaps) stands at 12.8% (A/E 1.09; IV 1.39). Only Beverley and Wetherby have a better win strike rate for front runners at this trip than Chester; and we can probably ignore Wetherby because there have been so few races (just 11) on their recently opened flat track. At the other end of the scale, front runners at this distance at both York and Epsom have won a meagre 5% of races.
As the field size gets bigger the pace bias strengthens a little: in races of 11 or more runners, front runners have won just over 25% of them (12 wins from 47 runners). Meanwhile, in terms of ground underfoot conditions, as with the extended 7f trip, it is difficult to pinpoint whether the going makes any real difference.
Now a look at draw / pace (running style) combinations for front runners in 1m 2f Chester handicaps (2009 – 2019):
It is easier for lower drawn horses to take the early lead but, in terms of these runners going onto win, strike rates are similar: low drawn front runners win 21.8% of the time; those who lead early from middle draws have won 20% of the time, high drawn front runners 19.2% of the time.
Chester longer distance races (8+ runner handicaps)
Looking very briefly at distances beyond 1m2f:
1m 4f - front runners over 1m4f do have an edge, winning around 16% of the time (A/E 1.50), but there is no draw advantage for any ‘third’ (47 races in total)
1m 5f – only 23 races at this trip and from the limited data front runners have a slight edge. There is no draw bias.
1m 7f 195yds or more – front runners have an edge even at this trip winning over 15% of the time (A/E 1.57) while hold up horses really struggle (3 wins from 125) producing an A/E of just 0.30. As the field size increases hold up horses find it even harder winning 0 races from 74 in races of 12 or more runners. In terms of the draw low draws actually seem to have a small edge which seems to increase in big fields. There have only been 30 races in total though so it is impossible to fully confident about these findings.
That concludes our investigation into draw and pace at Chester racecourse. As has been shown, there is a generally strong bias towards low draws and/or front runners, with the bias being emphasised in bigger fields.
- DR
Another well researched piece by Dave and very interesting but to be honest Chester is not a track I have wanted to get involved at over the years as just too quirky and way too many hard luck stories are in evidence on a regular basis but having said that will watch with interest when they race there again…
Excellent work Dave , i look forward to more of this from the other courses !
Good read this is my local track and I know it can be tricky to find winners but I still favour low draws and front runners. Keep up the good work.
Would be really helpful if a link to coarse articles could be put on the racecourse information .Ie when you click on Chester racecourse info the link to this article or articles is there
It is there John, like all other Chester pieces, in the section on the page called Chester Racecourse News.
Same for all tracks. Always has been.
Matt
Thanks Matt seems that long since I looked at a racecourse for selection process I had forgotten what information is there .
No Problem John. I am working on making it a bit more obviously there – one of many project plates spinning currently.
Matt