These ideas/rules are not mine. I have collected them from this forum and made them concise in this post.

There is more to testing systems then throwing a bunch of rules and then hoping for them to hold up in the future. Look for posts by Angry Pixie and wesmip1. These two seem to know how to analye systems.

A couple of pointers.

1. The number of selections needed to cofirm a system is usually effected by the odds of the selections. A system based on favourites might only need 2000 selections for confirmation. I system on long shots might need 10,000.

2. Use the chi square test to determine how luck has affected the results.

3. Test over at least a years worth of results and check the progression holds especially over the last month or two. If your lost in the last month of testing be very careful with it.

4. When testing over at least a years worth of results you want to see at least 8 or more months showing a profit. Preferably 10 or more.

5. Plot out the bar graph of X bets of the POT and check it looks like a bell curve. If its not showing a bell curve you have not tested enough. If it does show a bell curve check the middle of it sits to the right (positive) of 0. X bets should be at least 30 bets or 5/(1/[average odds]) and no more then 5% of the total number of bets.

If it passes all the above tests then you have found a long term keeper.

Excellent posting UB.

Concise it is however, so 1 or 2 questions if I may...

1. How big a sample with a strike of say 75%-80% ?

2. Do you have an equation for this so that we can check different SR's

3. Please clarify your logic regards point 5 in relation to sample size and odds

X bets should be at least 30 bets or 5/(1/[average odds]) and no more then 5% of the total number of bets.


Cheers LG

PS any chance of a resurrection for the system tester in 2013?

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The trick isn't finding profitable angles, it's finding ones you will bet through the ups and downs - UB

Good post UB.

I used to be a big believer in Bell Curves, but thanks to advice from iirc Angry Pixie & other reading etc, not so much these days - provided the chi-test looks ok with a good sized sample that's probably good enough.

Another approach that may help is to drop the top & bottom 10% of SP's from results & see how it holds up.

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"Now let me get this straight - Whatever I do don't bet this horse?"

I go with gut feel but I would need at least 300 for a 75% strike rate.
You could use at least 200 winners as the general rule. So if your strike rate is expected to be 75% then you get a winner every 1.33 races determined by 1/.75. So in this case you would want at least 266 selections.

See above.


You determine your POT for each expected 5 winners as a minimum. So if you had average odds of $10 then it would require at least 5/(1/10) = 50 selections. If your average odds was $2 then you require at least 5/(1/2) = 10 seelctions.

Personally I use a minimum of 30 bets per sequence. Lets assume I havea system which has 900 bets tested. I can divide this up into 30 bets each sequence. You work out the profit for each 30 bets sequence and plot it on a bar graph. You should see most of the POT's be around a certain figure and show a bell curve. If it doesn't show a bell curve then you have not done enough testing.


I do need to get this going again. I haven't had a chance to set it up though.

I think you need to use the chi test but it is suseptible to back fitting. The bell curve analysis ensures that there are enough results tested. If the bell curve is smooth then you should be right. If its jagged or has no shape you are likely to have backfitted results.

Yes, that's the approach I used as well UB, using the Bell Curve confirm Chi-test results to satisfy myself I hadn't back-fitted, however I found that depending on grouping size the bell curve could vary wildly, & that was with large sample sizes (>5000 races, grouping sizes from 25 to 50), so I lost confidence in it.

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"Now let me get this straight - Whatever I do don't bet this horse?"

Thanks for feedback UB.
Also some good balancing points from you NR.

I will venture further into testing the short end of returns from here.

Cheers LG

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The trick isn't finding profitable angles, it's finding ones you will bet through the ups and downs - UB

Nothing wrong with these ides if you have the data to test on, but what if you have some ides you want to test?

A few years back a post was made for testing systems without a data base.

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thanks Shaun. Very useful for those who don't collect the data.

The problem with most punters is trying to gather the the sample size, for which some members will try to compensate by testing back 12 years.

I've tried to explain that in getting a true POT, in reality you need thousands of bets for a system to properly gauge its performance. So does that mean you would need quite a few 1000 years to achieve that with a system like one with 20 bets per year?

This isn't possible, and so many people report that their system didn't work when it might be a winning system.

Even if you have a system with 50% strike rate the possibility of having 10 losses in a row is very real possibility

Most people tend to launch into a system after it has exhibited great performance, given that a system has a stable line of performance any deviance ABOVE this line will be followed by a deviance BELOW this performance line. SO guess what most people cop when they start ? Yep, the natural deviance to below the performance line to return the system to its normal average performance.

There is no answer to help you gauge the performance of your systems so that you can be absolutely certain, unfortunately!

So stick with your systems, if that is your punting method. For me I test over 5 years into portions because at the end of the day - the horses don't understand all the figures and trainers have change of styles, weights change and jockeys have bad runs. Each to their own and don't get convinced by others your methods are incorrect.