Common mistakes in system creation – the numbers may not appear what they seem to be.

It is often said that knowing when not to bet is just as important as knowing when to bet. In fact, it is something that should be imprinted on your mind.

I know a lot of people who bet far too much and they really do not know when to draw stumps on their days’ punting activities. It is easy to do and is all too common.

Most pro punters are very selective, often sitting out days or weeks at a time until they find the bet they have been waiting for and then they go in, usually to fairly hefty stakes.

The same can be true of system creation. It can be a very worthwhile pastime and you see many a system on the market that promises you untold riches if you first part with your own hard-earned cash. Many of these are just cons. Others are genuine but simply do not perform when put to the test.

Researching your own angles and creating your own systems on the other hand can be very rewarding. However, it is not without its pitfalls. One of the common mistakes is judging the potential of a system based solely on strike rate, profit and loss (P/L) or a combination of both.

When researching an article on horses running again within 7 days, I came upon many a good example of an apparent system that seemed to return a hefty profit at an excellent strike rate.

However, when looking deeper into the actual results, the reality was somewhat different in terms of any potential future profits. I thought it would be a good chance to use these examples to illustrate some of the pitfalls of system creation.

The System

We are going to be looking for a system for horses returning to the track within 7 days of their last run. Given the time of year we will stick to flat turf races and HRB allows us to dig as far back as 2003. These are the core elements of the system to give us something to work with. We are also going to look at those horses that won their last race as these are often turned out again quickly before the handicapper can give them a new official rating.

First, looking at the last few seasons, you typically see around 400 to 500 last time out winners racing within 7 days of winning (i.e. they are turned out after 1 to 7 days of their win) and the strike rate is about 22% for the win and around 47% for the place. In other words, just under 1 in 4 last time out winners that are turned out again within 7 days manage to follow up, and around half of them land place spoils.

Horse Race Base has data for Betfair SP from 2008 onwards and, interestingly, backing these runners blindly would have returned very healthy level stakes profits at Betfair SP in 2008, 2009, 2010 and 2011. Punters and bookies alike appeared to have cottoned onto this and since 2012 there has been four losing years and two winning years.

However, the number of bets and strike rate is consistent since 2008 and that certainly gives us something to work with to see if we can unearth some patterns lurking beneath those numbers.

The first angle I want to explore is the winning distance of the last time out winners. The more impressive the win, and the greater the winning margin, the greater the hike in the weights from Mr Handicapper. However, prior to reassessment he can only dish out a maximum penalty. For example, if a horse is due to go up 10lbs and runs within a week under a 6lb penalty, then they are effectively 4lbs “well in”.

The first thing to note from the table below is that there is a steady increase in strike rate corresponding to increasing winning distance. This fits with horses being “well in” when running under a penalty. Horses that won their previous start by up to 2 lengths have an approximate strike rate of 15% to 20% in their next race. Horses that won by 2 to 3 lengths have a 26% strike rate and those that won by 3 to 4 lengths have a 30% strike rate. Those that won by more than 4 lengths all have a strike rate of 29% or higher. We can ignore the eleven last time out winners who won by a country mile as they are few and far between and the sample size is too small to make any inference.

The other thing to note is that the P/L figures for industry SP are based on data going back to 2003 and the P/L for Betfair SP only goes back as far as 2008, hence the discrepancy. Looking solely at Betfair SP we see a level stakes profit for all last time out winners that won by a short head to 4 lengths (with the one exception of the group that won by a neck). In comparison, we see a loss at industry SP pretty much across the board with the one standout exception of those that won by 3 to 4 lengths, where a level stakes profit of £41.65 was made. To try and make more sense of this data I have recalculated the numbers for winning distance from 2008 onwards so we can get a direct comparison between industry and Betfair SP. Seeing as betting to industry SP is largely irrelevant and betting to Betfair SP is commonly employed, we will concentrate on 2008 onwards.

When we concentrate on those last time out winners whose winning distance was up to 4 lengths we are left with the following figures since 2008.

Whilst the P/L is pretty good at Betfair SP, the return on investment is a shade under 7% which will not appeal to many people but in reality is not bad at all. The thing that you have to do next is to look at the yearly breakdown of results, which are quite interesting:

You can see that there have been four standout years. In 2008 the P/L to Betfair SP was £59.76. In 2010 the level stakes profit was £65.33, rising to £109.61 in 2011 and finally in 2013 the profit was £53.91. What is interesting is that the years 2014 to 2017 (currently the end of May as I write this) show a combined loss (albeit not a huge one).

The strike rate does not appear any different from year to year so I can only suggest that last time out winners are now either overbet or the bookies have dived for cover. It is most likely a combination of both. Perhaps the majority of casual punters having a wager look no further than recent form.

We have lumped together those last time out winners returning after 1 to 7 days, so it is worth splitting those out to see if there is any pattern with respect to the actual days since they last won.

From the results above we see that those returning within 5 days have a better strike rate than those who returned after 6 or 7 days. Although the results are shown as 6 to 10 days, this is just the sub-category that HRB uses and it is essentially 6 to 7 days as we specified no more than 7 days off the track in our core system criteria.

Looking at Betfair SP we see that the majority of the profit comes from those racing after 4-5 days and 6-7 days. That may be a result of the fact there are just far more runners who return after this length of time compared to those turned out again more quickly. Personally, I would say there is not much difference given the relative strike rates across the different time frames and I would move on from here.

Race class is always an interesting angle and I have looked at last time out winners since 2008 returning to the track within 7 days across the different race classes. It may be that we have to go hunting in the bargain basement as the table below shows:

Concentrating on strike rate (Win %) and you can see that the horses racing in the lowest grades have a 26 to 30% strike rate. This compares with about 10 to 18% in classes 1 to 3 and about 22% in class 4. Clearly, exploitation of handicap marks is easier at the lower end of the scale. Combing classes 5 and 6 we get the following results:

The return on investment is a couple of percent higher than we saw previously when backing runners blindly. As always when looking for any potential system you should not be drawn in by the bare figures for strike rate and P/L and always break the results down by year to see if things have changed in recent times.

When we do this we see that this type of system worked really well from 2008 to 2011 and has then tailed off completely. As we mentioned earlier, this is most likely a factor of the bookies not taking any chance on those runners turned out again quickly and the punter who looks no further than that last time out win.

Whatever the case, it looks like it is becoming increasingly difficult to turn a profit from backing last time out winners returning to the track within 7 days, even in the basement classes.

Even if we revisit those that won by anything up to 4 lengths on their last start and add that into the class 5 and class 6 angle, we see similar results. Whilst the overall figures from 2008 to present day look encouraging, the recent years have not been anything to write home about.

There are a few other angles worth exploring. The first is the age restriction for handicap races.

Now we begin to see something interesting, with the 3yo+ handicap race being responsible for pretty much all the profit, albeit from the vast majority of races. However, once again when we look at the yearly breakdown of results we see the same pattern emerging in that what once worked well appears to have stopped working:

If you had run this as a system from 2008 to 2011 you would have been quids in. You could also have been forgiven for thinking you had found the holy grail of betting systems with a 20 to 25% strike rate and yearly profits to boot.

This is not the case anymore and this is another example of the changing landscape of the betting world. Bookies are sharp when it comes to shutting such profitable systems down. The strike rate has not changed so the horses are still winning as expected. However, the value has long since gone and prices on last time out winners being turned out again quickly are best described as prohibitive.

Herein lies one of the problems of system creation and of following profitable systems over a cliff. Things that worked a few years ago, just no longer work anymore. The horses don’t know this and they keep winning as you would expect, but the value has been squeezed out of the markets and the profits appear be a thing of the past.