Run Style Bias in Non-Handicap Chases
In this fourth and final part of my investigations into run style bias in National Hunt racing, I'll look at the effect of pace, or run style, in non-handicap chases, writes Dave Renham.
The previous three parts can be found below:
- Run Style Bias in Handicap Hurdles
- Run Style Bias in Non-Handicap Hurdles
- Run Style Bias in Handicap Chases
Run style is all about the position a horse takes up early in a race. Here at geegeez there is a pace section which splits the early positions of horses into four groups. The groups are called Led, Prominent, Mid Division and Held Up. Each group is also assigned a numerical value starting at 4 for led, and then 3 for prominent, 2 for mid division and 1 for held up. Essentially, ‘led’ means horses that led the race early, also known as front runners; ‘prominent’ equates to horses which race close up behind the leaders; ‘mid division’ refers to those racing in the middle portion of the field; while ‘held up’ covers the cohort close to or right at the back of the pack.
For this piece I will look at races with seven or more runners – for the other articles I used eight as my cut off, but non-handicap chases too often have smaller field sizes so I wanted to increase the overall data set. Indeed, despite including seven-runner races, in recent seasons the average number of qualifying races per year has been less than 100. That's quite a difference from the 2009 season when there were 226 qualifying races. Note also that hunter chases have been included in this dataset.
Overall Run Style Bias in Non-Handicap Chases
The first set of figures I wish to share with you are the overall run style stats for all National Hunt non-handicap chases in the UK from 1/1/09 to 31/7/21. These have been sourced from the excellent Geegeez Query Tool:
There is a definite advantage to early leaders / front runners here, with prominent racers notably second best. Horses that race mid division or are held up have remarkably similar records, both poor in relation to those campaigned more forwardly.
The strike rates for each run style section have stayed extremely consistent over the last 12 years or so, as the following bar charts illustrate. As with previous articles I have split the non-handicap chase data into two in order to compare 2009 to 2014 run style results with those for 2015 onwards. The bar chart below compares the win strike rates (SR%) over these time frames:
The difference in percentages is not significant when factoring in the reduced field sizes, so we can reasonably expect these run style patterns to continue in the coming season and over the coming years.
Onto the A/E values now and their comparison over the two time frames:
Again, there is very good correlation within the respective run style groupings.
The general pattern is clear, so let's drill down into different areas to see what differences, if any, there might be. With the data being consistent enough across the two halves of time I will analyse these areas over the whole period (Jan 1st 2009 to July 31st 2021).
Run Style Bias in Non-Handicap Chases by Distance
I have split all race distances into three groups, as I did in the previous instalments in this series: the groupings are 2m 1f or less, 2m 2f to 2m 6f, and 2m 7f or more.
2m 1f or less
The shorter distance races seem to accentuate the front running bias. In addition hold up horses perform more poorly than the 'all distance' group. The stronger front running bias can be appreciated more clearly perhaps by comparing SR%, A/E values and Impact Values (IV) between these 2m1f or less contests with races of 2m2f or more:
Let us now split the last two groupings up and you will see they are similar, still giving an edge to front runners:
2m2f to 2m 6f
2m 7f or more
One factor to keep in mind in non-handicap chases is that there can often be a significant ability bias; that is, the horses at the front are frequently a good bit better than some of those at the back.
Run Style Bias in Non-Handicap Chases by Course
Let's move on to specific racecourses. The problem when slicing data to the course level is that sample sizes are quite limited, especially when focusing on specific course and distance combinations.
Only twelve specific course and distances have hosted thirty or more qualifying races during the period of study. These are the strongest front running biases from that small group:
Chepstow 2m 7f or more
At Chepstow they tend to race over 3 miles exactly (officially, at least). Twice in the last 12 years they have raced over further. Here are the run style splits by strike rate:
Leaders seem to have enjoyed a huge edge at the Welsh venue. The A/E values back this up from a betting perspective:
Front runners enjoy an A/E value of over 2.00 (2.16) with all other run styles falling well below 1.00.
Exeter 2m 7f or more
At Exeter they race over 3 miles only. Here are the front running strike rates:
While not as strong as the Chepstow bias, it is still far more beneficial for a horse to be ‘on the front end’. Moreover, the prominent racer stats are strong, too, suggesting that this is not an easy C&D over which to come from off the pace. A/E values for the same now:
Again, we see good correlation, backing up previous observations. There is a less striking disparity between front of pack racers and later runners than at Chepstow's longer distance, but it is still comfortably the difference between long-term profit and the poor house.
Cheltenham 2m 4f and 2m 6f
Combining these two trips across the two courses (New and Old) at Cheltenham shows that that even with the fiercely competitive racing, and the individual track nuances, front runners remain the value:
As you might have come to expect the A/E values mirror the above run style split:
These are the three strongest course and distance run style biases I could find with big enough datasets. There will doubtless be others but some 'flyers' will need taking due to the small samples.
Run Style Bias in Non-Handicap Chases by Race Class
With such limited useful data at the course level, I decided to explore alternative areas. Class of race is something I have analysed before in relation to run style, but never in non-handicap chases. I decided to split the class of race into three groups, namely Classes 1 and 2, Classes 3 and 4, and finally Classes 5 and 6 (including the majority of hunter chases). Here are my findings for strike rates:
Now this is interesting. The orange bars, showing Class 3 and 4 run style results, clearly indicate at this class level the front running bias is at its strongest. Looking at the lowest class group (5 and 6) there is a front running edge but it is somewhat diminished. The highest Classes (1 and 2) have very similar figures for front runners and prominent racers. Those forward groups still have the edge on hold up horses but the bias is less potent than with the Class 3 and 4 group.
There are many ways one could interpret these findings. I am going suggest the following.
Firstly, in Class 1 and 2 races, these are often more competitive and hence it may be harder for front runners to repel later running challengers with a touch of quality. In Class 5 and 6 races, I surmise that front runners have less ability and, as such, are unable to sustain their pace throughout the whole race, thus fewer end up winning.
Finally, then, Class 3 and 4 races may then be the sweet spot, with horses that lead early having enough ability to see a race out while being faced with slightly lesser calibre rivals compared with Class 1 and 2 contests.
The above is, of course, just one interpretation and I may be wrong. Racing, and particularly analysing and betting on racing, is as much about opinions and theories as it is cold hard data.
Run Style Bias in Non-Handicap Chases by Field Size
My next port of call was to look at field size to see if smaller or bigger fields had any bearing on run style stats. I have again split the results up into three groups – races with 7 or 8 runners; those with 9 to 11 runners; and those of 12 or more runners.
For field size one needs to look at A/E or IV values rather than strike rates. Strike rates give an inaccurate comparison as seven-runner races are going to produce higher strike rates across the board than, say, twelve-runner races. I've used A/E as it offers an indication of market potential, higher numbers (above 1.0) leaning towards a suggestion of future profitability.
The bar chart below compares each section.
The data suggest that there may be less of an edge to front-runners in mid-sized fields (9 to 11). Unlike with the class data, I cannot offer a ready explanation for why this might be the case. I had expected smaller fields to do quite well in terms of front runners due to the limited competition numbers wise, but I had not expected bigger field races of 12 or more runners to be on a par with 7- or 8-runner races, however.
Run Style Bias in Non-Handicap Chases by Going
I wanted to study the going to see if faster or slower ground conditions made a difference. Here, I have split the data in two – firstly good going or firmer; secondly good to soft or softer. The bar chart shows the findings. The blue bars are good or firmer; the orange good to soft or softer:
One could argue there is a slightly stronger front running bias in softer conditions, as well as it seeming to be harder to win from the back or near the back (held up) when the turf is wet. However, the differences are relatively small so I'm not fully confident that this is the case.
Trainers showing a Front Running Bias in Non-Handicap Chases
Let's finish off by looking at trainers' front-running percentages. Below is a table highlighting the percentage of runners from a given trainer that front run. This type of information can be very useful when trying to work out which horse might lead early in a race, especially when there is little evidence in the form book. Here I have included those trainers with at least 50 runners under the conditions (7+ runner non-handicap chases, 2009 to end July 2021) :
There are some huge variations!
Donald Mc Cain’s runners lead over 39% of the time, just about four out of every ten runners; and Rebecca Curtis also seems to favour the front running option: not only do 31% of her horses take the early lead but 30% of those which lead have gone onto win their respective races.
Run Style Bias in National Hunt Racing Overall Summary
Looking at the four articles in this series as a whole, I hope readers can see the unarguable edge that front runners have in National Hunt racing. It is true that some front running biases are stronger than others, but in every article, thanks to a bit of extra digging, useful angles and stats have emerged to be deployed throughout the autumn, winter, spring and beyond.
If you have never personally researched run style angles or ideas, I really recommend doing so. Geegeez gives you the tools to unearth profitable pace/run style angles that very few other punters know about. And the great thing is, gathering and crunching data on Geegeez is a quick (and, dare I say it, fun!) process. Gone are the days of scrolling through formbooks and looking at one race at a time.
When you do find something interesting, or if you have any ideas you’d like me to research, please post them in the comments below.
- DR