What Is Draw Bias in Horse Racing?

Racecourse viewsSimply put, draw bias in horse racing refers to the presence of an advantage or disadvantage gained from starting in a particular stall, or more often, group of stalls (low, middle or high). In flat racing, horses are allocated a specific stall, or gate, from which they need to enter in order to start the race.This allocation is performed at random, unlike during many athletics events for example, so you do not have a situation where the favourites always end up with the most optimal draw.

You can easily spot which stall a horse will begin the race from by checking the racecard. Just note that the draw will usually not appear well in advance, often it is made just a day or two prior to the race start. We have included an example below so you can see yourself where to find it.

Finding the Stall on the Racecard

Draw bias example: Roman MistIn this case the horse, Roman Mist, will begin from stall number 3, the smaller number in brackets on the left. The larger number five beside the three is a separate number used mainly for the purposes of referencing. If placing your bets with an on-course bookmaker for instance, you would typically say £10 on 5 rather than £10 on Roman Mist.

Regardless of whether the course is anti-clockwise or clockwise, stall number one will refer to the spot by the inside rail. For decades this had not been the case at right-handed courses but in 2011, the British Horse Racing Authority announced the changes, partly to bring the nation in line with the rest of the world. We can tell you that it saves a lot of potential confusion when carrying out draw bias analysis!

In the event a horse pulls out of a race, after the draw has been already determined, their stall will simply remain vacant rather than every other horse shifting up one. It is for this reason you might see the odd race where there is a substantial gap between two particular horses as they fling themselves out of the gate.

Why Bother Using Starting Stalls?

Horse race starting stalls

Credit: mikle / Bigstockphoto.com

We have spoken a lot about the starting stalls/gates in the above section and you may be asking yourself why even bother with them? They are quite cumbersome for starters and require staff to physically move them to the starting point of a particular race. You also need ‘stall handlers’ to help get horses into their correct spot and to keep them calm as some can get a little restless due to the restricted space. Indeed, it is not uncommon for it to be very difficult to get all the horses into the stalls, with various techniques and devices used to urge, cajole or even almost force horses into place.

They are also quite expensive units given each stall has an electromechanical release system, all designed to open simultaneously at the press of a single button. York racecourse spent a six-figure sum to get a 22-stall starting gate all the way from Australia in 2018 and of course these contraptions all need maintaining too.

The Benefits

There are two main reasons why the stalls are used (and subsequently why a draw is made). One is fairness. The old-fashioned method of getting horses to line up behind a rope or tape is rather imperfect. You will find that some horses are touching the rope but others are not, instead stuck behind other horses.

By having doors that release at exactly the same moment, every horse has an equal chance to get their nose in front first. The older systems also have a greater tendency to produce false starts with some horses jumping the gun, quite literally. With nowhere to move, horses in flat races do not have this opportunity and a fair start is guaranteed first time, every time.

No Stalls Used in NH Races

You will not see stalls used in jumps racing and this is because these contests do not take place over sprint distances. Indeed, the shortest NH race is some two miles, whilst flat races can be just five furlongs, with most of the prestigious flat contests not too much longer or shorter than a mile.

Just as when humans race at the athletics track, starting stalls, or blocks for humans, are only necessary for the sprint distances. Over longer distances the start is less pivotal and because runners, equine or human, have plenty of time to make up any lost fractions, a rope or take is fine.

When Should I Look Out for Draw Bias?

Horse race start

Photo © mikle / Bigstockphoto.com

Virtually all flat race meetings across UK and Ireland across will use starting stalls and will allocate horses a specific stating position. That said, there are some flat races, usually the longer contests, that do not use stalls. We would expect any meeting on the flat to host at least a couple of events run over a distance where draw bias might have a potential impact (usually races from five furlongs, up to about 1m2f).

Look further than this and you will not find much in the way of insightful results because the more there is to run, the less impact the starting position has. At some courses you can see some minor trends at 10 or even as far as 12 furlongs but this is what we would consider to be the absolute upper limit.

One other major consideration when it comes to draw bias is the number of runners involved in a race. Generally, you will not find much analysis that takes place on fields featuring fewer than eight or 10 horses. With fewer horses than this there does not tend to be much in the way of meaningful bias, largely because the participating horses are not very spread out. So, as a rule, you should only give draw bias its full consideration when you have a minimum of eight horses.

Is There Draw Bias for Jump Racing?

Draw bias analysis does not take place for National Hunt (jumps) races. For starters, as said, hurdles and steeplechases have a minimum distance of two miles and over this sort of distance, where a horse begins, width wise, has virtually no impact. Even if they held shorter races though, there is no telling where a horse might start as there are no starting gates and thus no draw.

Horses just find a spot by the tape before being sent off on their way when the gun fires. Some inevitably end up having a poor start stuck right at the back (perhaps a couple of lengths back in bigger races) but it’s impossible to predict which horses that will affect, though of course some horses may be known as being especially good or bad starters.

There are such things as National Hunt flat races, also know as bumper races, that tend to be around two miles long but you can see them as short as 12 furlongs. Just like with jump racing though, horses begin in one big clump rather than starting stalls, partly because these bumpers are meant to serve as practice for eventual jump horses. Therefore, you cannot carry out any gate analysis for these contests, even if you wanted to.

Draw Bias Terminology

Terminology

Detailed draw bias analysis is not something that tends to pop up during your typical conversation about racing. Even the pundits do not tend to cover it in much detail, certainly not to the level that is possible and you may see on specialist sites. Everyone has their own method for picking horses but if draw bias is something you really want to factor in, it can all get quite statistical. By crunching lots of numbers you can create various different ways of looking at draw bias and its potential impact.

ROI Figure

One of the commonly mentioned metric is the return on investment (ROI) figure. A ROI figure of +20% shows us that an equal stake across horses within a particular group e.g., ‘low stalls’ would see you claim a 20% profit margin. While a useful indicator to see overall profit/loss trends, the slight issue with ROI is that all it takes is a couple of big money winners to skew the overall picture.

Impact Value (IV)

It is for this reason that we consider Impact Value (IV) to be a superior metric. If things were perfectly fair, each draw (low/mid/high) would have an IV of 1.00 across a large set of analysed races. This indicates that horses across all stalls have performed, on average, as well as they should have done, no better no worse. Scores close to 1.00 (0.9 to 1.1) indicate very minimal difference which is unlikely to be of any statistical significance whatsoever. It is only when an IV reaches around 0.8 (or lower) or 1.2 (or higher) when would we begin to pay close attention.

A rating of 0.8 for low drawn runners for instance would indicate they are at a noticeable disadvantage. Conversely, a rating of 1.2 for mid drawn runners shows this is a beneficial place to start. Naturally, there is correlation between IV and ROI. Where IV is low, for example high runners at Beverly across 5f (0.62), the ROI is also poor at -48% (data taken from April 2011 to April 2021).

What Causes Draw Bias?

Beverley Racecourse

Beverley Racecourse has the most pronounced draw bias (Photo © Paul Glazzard / geograph.org.uk)

British racecourses really do come in all shapes and sizes and that is part of what makes the sport so fascinating. For a one-mile race, some courses might allow horses to simply run in a straight line. At others though, competing thoroughbreds may face a sharp bend just two furlongs in, or sometimes even sooner.

The Shape of the Course

The positioning and sharpness of any full bend or even partial curve is often one of the biggest contributors of draw bias. If you spend half a race on the turn, being out wide means a lot more distance to cover, at least relative to the overall length of the race. The location of any cambers or ridges is also something that can play a part, as can the extent of surface kickback on all-weather courses.

State of the Turf

You also have to give some consideration to the state of the turf. Certain areas on certain courses can for example, drain better than the rest of the track and therefore they tend to be quicker. This is why in some races (flat and jumps) you might see jockeys drift towards the outside rail. As a result, you will inevitably find that conditions on the day often influence the extent of any draw bias, in either direction.

This also means that courses may only a particular bias under certain conditions, for example when the going is soft or worse. It can also explain why sometimes the draw bias may operate counterintuitively, for example favouring horses drawn on the outside of a bend.

Sample Size Visibility

One final point to stress here is that if draw bias does exist, it should be visible over a large sample size. By only looking at five or 10 races, you are in danger of finding trends that are simply random fluctuations, rather than an indicator of inherent course bias. After all, the draw bias usually only makes for a fairly minor disadvantage or advantage in the grand scheme of things.

It is not akin to being saddled with an extra three stone. To spot something that is significant, but still a relatively small factor, you need a large sample size. There is no magic number for this, it is simply a case of the more races you have, the more confident you can be with your conclusions.

Is Draw Bias Present at Every UK/Irish Racecourse?

Southwell Racecourse

Southwell Racecourse is one of fairer courses in terms of draw bias (Photo © Chris / geograph.org.uk)

As we have already established, draw bias is strictly reserved for flat races, usually no more than eight or nine furlongs long. The next question to ask is if draw bias is a factor across all shorter-distance flat racing? The answer to this is no. There are many UK and Irish courses out there that are what we would consider to be very ‘fair’. This means a horse’s chance of success are not influenced, in any significant way, by their starting position. It is at these courses where you do not need to consider the draw when placing your bets.

There are plenty of other courses, which are inherently “unfair”, with certain stalls far more sought after than others. The extent of draw bias at these venues varies quite a lot too. In some cases it is fairly mild with only a small advantage gained from certain positions. As we will discuss more below though, at others it plays a huge role and a poor draw can be a tricky obstacle to overcome.

‘Famous’ Draw Bias Courses

Chester Racecourse

Chester Racecourse (Photo © N Chadwick / geograph.org.uk)

There are two fairly undisputed kings of draw bias, Chester and Beverley:

Chester & Beverley

At both, there is a major disadvantage to being drawn further out wide. Due the extremely sharp and circular nature of Chester’s course, known to fans as the Roodee, the bias strikes across just about all distances.

For races 5f to 8f that featured at least 10 runners between May 2011 and September 2020, the winning % for low drawn horses was 14.2% compared to just 5.3% for high drawn. At Beverley, the bias is only really for 5f sprints as this takes place on a straight (ish) course with a slight right hand dog-leg. Here low drawn horses posted a win rate of 11.4% with high drawn runners successful just 5.4% of the time.

Thirsk

Another course that that tends to feature in draw bias conversations is Thirsk, even if the extent of the bias tends to be a little overexaggerated. Despite it having a straight one-mile track, decade long data taken from races featuring at least 10 runners shows a distinct advantage for a mid/high draw horse.

Goodwood

When looking at all events between 5f and 8f, low drawn runners post a low impact value of 0.79 and a 6.5% win rate. Finally, we would also like to give Goodwood a mention. Although many are aware of the bias that exists here, its impact is often understated. Using the same search criteria as with Thirsk, low drawn runners won 10.3% of the time compared to 4.4% for high drawn.

Is Draw Bias Accounted for by the Bookies?

Bookmakers factor in a whole range of things when determining odds for a particular race. If the draw is one of their considerations though, then the stats show they are not doing a particularly great job. To give you a very distinct example, at Goodwood (discussed above) high drawn runners reported a -57% ROI compared to -1% for low-drawn runners.

This goes to show that typically horses starting from the outside are priced far too short and generally represent poor value for money. It is worth bearing in mind that betting activity does shape the odds too, so while a horse may start at 10/1, they could end up at 6/1 by the time the race starts if punters flood to back it. The end result is still the same though in that certain draws are just significantly less likely to turn a profit in the long run.

A Final Word

We believe that draw bias is a largely underrated tool in the arsenal of any punter. It is possible to get very detailed and informative draw statistics that can help pick up trends most other bettors are not taking into account. At some courses, draw bias is very real and it can ultimately shape the nature of a contest significantly. This is especially true given that many races are settled by no more than a length or two. A good draw can easily be worth these kinds of small distances.

That said, while draw bias definitely has its value, it should not be used as the main deciding factor in your bets. All the draw does is tip the scales one way or another, at some courses only slightly. There are so many other considerations you can factor in such as horse form, trainer form, course record, distance record, handicap, headgear changes, selected jockey, expected race pace, going etc. With so much to take into account, we can understand why some people simply like to stick with their gut feeling!