Up In Weight - Better Chance!!!!

[TESTAROSSA]

I read with interest an article written in this months edition of PPM by columnist E.J Mimmis about weights.

He was replying to a question which asked how do horses that have been beaten by a certain horse get a significant weight pull in there next meeting but that certain horse still beats it.

His reply was that he thought the bigger the rise in weight from last start the bigger the advantage.

He went on to say "... weight was one of a number of factors that i researched , finding a weight increase a far more positive factor than a weight decrease , as the follwing statistics , which are based on hundreds of thousands of individual horses runs , show:

Horses dropping weight by 3.5kg or more: 6.2% strike rate.

Horses dropping between o.5kg and 3kg:
7.4% strike rate.

Horses carrying the same weight:
7.8% strike rate.

Horses rising in weight between 0.5kg and 3kg:
11% strike rate.

Horses rising in weight by 3.5kg or more:
13.9% strike rate."

I thought those statistics were so unbelievable at first i had to re-read it to make sure i was reading it right.

In my ratings approach i gave horses rising in weight by 2.5kg or more a penalty while giving horses dropping by more then 2.5kg a bonus , i think i will be re-thinking that approach very closely now.

What does everybody else think about those statistics?

[noel]

testarossa,
interesting stats....there are varied opinions as to the effects of weight...stats show topweights win the most number of starts (as a ratio to the number of starters) and in fact an english writer called russell clark believes the disadvantages of weight are much overrated....he cites his own stats on english races which show much the same trend as you did....on the other hand i have followed with interest neil's weekly stats on horses carrying 59kg or more...they distinctly show a marked loss if you back these horses ....i wonder what the stats would be with topweights carrying less than 59kg??

[Dr Pangloss]

Below is a UK article backed by comprehensive statistics confirming that, from one race to the next, horses going up in weight win more races.

http://www.flatstats.co.uk/articles/weight_in_horse_racing.html

[Equine Investor]

I am can confirm that this is correct on strike rate.

I am currently doing an analysis myself on weights and the impact of them over three years of saturday metro racing, when I finish, I'll post the results here.
It won't be for at least a week as I'm only a quarter way through it and it's very time consuming, but already this pattern seems correct.

E.J. has some great statistics he uses but some of his conclusions leave a lot to be desired given his statements on the Ausrace message system.

[osulldj]

I have for a long time now largely discounted the effect of weight and since that time my profit has improved, partially because I believe weight doesn't have the effect people believe, but perhaps more importantly that everyone else still considers it important, which creates windows of value opportunity for me sometimes.

I can support EJ's stats in PPM with my own work from some time ago...which if I present them in the same categories as him show:

(Based on 3 years of NSW/QLD/VIC/SA Metro racing).

* < -3.5kg's = 6.5% SR and -25.5%POT

* -0.5 to -3.5kg's = 8% SR and -22.9%POT

* Carrying the same weight: 8.5% SR and -17.9%POT

* +0.5 to 3.5kg's =11.5% SR and -19.4%POT

* >+3.5kg's = 13.6% SR and -19.7%POT

Statistically speaking, EJ is of course right, a weight increase is a positive statistical factor and a decrease is a negative factor. EJ was answering a specific reader question and did so in an excellent manner but excluding that, these figures about weight change in isolation of other factors add no value to the handicapping process. They do nothing to help us make profit.

In racing, weight change takes place in the context of class changes i.e. easier or more difficult opposition from race to race. The reason then that horses rising in weight win more isn't because extra weight speeds them up, its because more often than not it means they are contesting an easier (or at worst same) level of race as previous. Taking this further, the reason horses higher in the weights win more is purely because they are better than the opposition, not because having a higher weight makes you run better.

So weight cannot be considered in isolation in a handicapping process and I believe anyone who applies penalties or bonuses based on weight changes or amnount carried alone is making a fundamental error in race and horse assessment.

The real issue in racing is whether the horse has the ability to win at the given level of race. If you are assessing weight it must be more in the context of the change in class and the horses ability to compete at that level.

If a horse is dropping in weight, it should not receive a bonus nor an autmoatic penalty because the stats say its a negative factor.

The view we must take is to assess whether the horse has the ability to win at that level of class, if it doesn't, then no amount of weight reduction will help it so why apply a bonus? If it has proven capable of winning at that class with the same or more weight in the past, then why would we apply a penalty for its weight reduction from last run?

If a horse is rising in weight and racing in a much easier class then we might conclude that it certainly has the ability to win and the weight will not be a hinderance. However if the horse is racing in similar class and only just managed to win last time, maybe the increase in weight is enough to bring it back to the field. Why would we apply a bonus in such a situation? Because the stats say a rise in weight is a positive factor and irrespective of other things, an increase in weight somehow magically improves a horses competitive ability in the upcoming race? I don't think so!

As you can see there is no easy answer, it depends on the context of the race and individual horse. That's why those who put faith in the search for statistical answers will in the long run always come up short. Not that I mind :smile:

They're my views anyway, interested in others comments. If time permits I will make another posting that examines class and weight changes when viewed together.

[osulldj]

EI, Unless you wish to, there is no need to go to painstaking amounts of work and time to research such statistics.

If you would like to see in anything in particular then I am happy to help and save you some of that work (without becoming your person data bunny :smile: I can analyse these type of things over thousands of past races with win, place and profits in a matter of minutes.

Just post what you would like and I will do my best.

[Equine Investor]

Thanks osulldj,

In fact your posting could not be truer and your assessment of statistics and how you apply them more accurate!

You cannot apply statistics solely on strike rate with out considering at least a few other variables.

Each race, in my opinion has to be treated as an individual event, but apply statistics based on the "weight" (pardon the pun) you give to each one.

The impact of weight over various distances has to be considered as well. Weight over 1000m or 1200m is vastly different to the impact of weight over 1800 or 2400m. This is where statistics can guide you in the wrong direction.

The reason that many of the topweights fail is not because of weight.
It is because they are weighted based on their best form not on their recent form. So you get out of form horses being given top weights and performing poorly.

They are then assigned topweight because they drop down a little in grade and are not at their peak formwise.

The ones that do win are usually in good form but have had luckless runs or beaten by a smaller margin.

So the stats are not a good guide if you only consider the raw data.
If you were to consider topweights which were beaten by less than two lengths at their previous start, over various distances I think you'd be get a better guide to the impact of weight.

As always it's the bigger picture to consider.

[Equine Investor]

If you would like to see in anything in particular then I am happy to help and save you some of that work (without becoming your person data bunny :smile: I can analyse these type of things over thousands of past races with win, place and profits in a matter of minutes.


Thanks for your offer ossulldj, but I'm doing a rather involved study. It would be unfair to ask for such detail. In other words I am considering weight with other variables.

For example:
1. Strike rate of each weight per race.
2. Strike rate of each weight per runner.
3. Strike rate of both of the above over every individual distance.
4. Strike rate of all the above over sex.
5. Strike rate of all the above over age.
6. Rises and falls in weight for each of the above.
It just goes on and on.
:eek:
It's more for my own curiousity than anything else as I'm kind of a stats nut and look at how best stats can be refined and applied to be useful.

[Neil]

Here are a few points to consider:

1. An increase in weight will NEVER improve a horse's performance.

2. An increase in weight will ALWAYS reduce a horse's performance.

3. The opposite applies for a decrease in weight.

4. The issue is whether the weight increase fully penalises the horse for the drop in class.

5. Similarly the issue is whether the weight decrease fully compensates the horse for the rise in class.

6. Some of the best long term bets may well be improving horses rising in class and dropping in weight.

<font size=-1>[ This Message was edited by: Neil on 2002-11-29 12:37 ]</font>

[Bhagwan]

Stats on wt increase.

0-3.5kg=28%SR -19% Loss on turnover
4-5kg=40%SR +26.6% Profit on yurn over
5.5-16kg 36%SR -6.8% Loss on turnover

[osulldj]

My earlier post above made the point that weight changes must be considered in the context of the class of opposition a horse is racing against.

Stats show that horses rising in weight win more than horses falling in weight, but that doesn't mean you should treat a weight increase as a positive or negative factor in your handicapping.

Weight changes up or down offer no value from a handicapping point of view without consideration of class, or for that matter other factors like fitness, distance etc. (as EI pointed out in his post).

I have spent quite some time researching and writing about various racing topics and following are the outcomes of my own previous analysis and thoughts on these issues which I am happy to share and invite your comments on:

INTRO
======
I examined weight carried changes for runners in three categories:

* -1kg to +1kg on last start i.e. much the same weight.
* 1.5kg and greater increase
* -1.5kg and greater decrease

Of course there are multiple groupings one could use but to demonstrate the principles of weight and class these three groupings are more than suitable.

Along with weight increases, changes in class from the previous race were considered:

* Much easier class
* Moderately easier class
* Much the same class
* Moderately harder class
* Much harder class

These judgements were based on grouping of the class values assigned to each race in the database I use for my racing activities. This database covers every single TAB meeting held in Australia but as in my previous post, the data used for this work was all Metro races in NSW, QLD, VIC and SA over 3 years.

WEIGHT CHANGE STATISTICS
==========================

Overall stats for weight change in the groupings used are:

* -1.5kg's or more = 7.6% SR and -23.1% POT
* -1 to +1 kg's = 8.7% SR and -17.9% POT
* +1.5kg's or more = 12% SR and -20.6% POT

As statistics show, horses rising in weight win more than horses falling in weight. However the significance of weight change doesn't become meaningful until we consider class change as well.

HORSES FALLING IN WEIGHT 1.5kg's or Greater
===========================================

Following are stats for these horses according to their class change:

* Much easier class: 9.7%SR and -10.7% POT
* Mod easier class: 9%SR and -18.9% POT
* Much same class: 8.1%SR and -24.9% POT
* Mod harder class: 7.8%SR and -25.3% POT
* Much harder class: 6.6%SR and -23.5% POT

Overall: 7.6% strike and -23% POT

Interesting?

HORSES RISING IN WEIGHT 1.5kg or Greater
========================================

Following are stats for these horses according to their class change:

* Much easier class: 13.5%SR and -16.7% POT
* Mod easier class: 12%SR and -23.5% POT
* Much same class: 11%SR and -13.8% POT
* Mod harder class: 8.1%SR and -25.1% POT
* Much harder class: 4.7%SR and -58.9% POT

Overall: 12% SR and -20.6% POT

DISCUSSION
============

Remember that overall it is supposedly a positive factor that a horse is rising in weight and a negative one that a horse is dropping in weight.

Excluding profit for the minute, weight droppers only have a 7.6% strike rate, yet weight risers have a 12% strike rate.

But weight risers racing in moderately harder class only have a 8.1% strike rate and a shocking 4.7% strike rate when racing in much harder class. How then can a weight rise by itself be a positive factor?

Weight droppers who are going to race in moderatelly easier class have a 9% strike rate and if in much easier class a 9.7% strike rate, better than certain horses rising in weight. Again, how can a weight change by itself be considered a positive or negative factor?

HORSES WITH MUCH THE SAME WEIGHT -1kg to +1kg's
====================================================

Following are stats for these horses according to their class change:

* Much easier class: 11%SR and -13.7% POT
* Mod easier class: 10%SR and -22% POT
* Much same class: 9.5%SR and -23.5% POT
* Mod harder class: 8.4%SR and -21% POT
* Much harder class: 6.5%SR and -17.9% POT


SUMMARY
=========
A quick glance at these figures shows that we can make no conlusions about weight change that have any valid meaning to our work as form analysts and punters. Irrespective of weight, horse going up in class have a significantly inferior record.

Some people claim that rising in weight is meant to be a positive factor yet the worst profit figures from this analysis come from horses rising in weight who are racing in moderately harder or much harder class. Quite ironically the next worst comes from horses who are falling in weight that are racing in harder class.

This leads me to believe that the market "underestimates the importance of class" and therefore overestimates the winning chance of horses racing in harder class. Also implied is an overestimation of the impact of weight, particularly decreases in weight when a horse is rising in class.

While simple statistics by themselves cannot offer us any winning advantage, there is no doubt that as an analysis principle, CLASS is KING. As Pitsburgh Phil said, "show me the man who can class horses correctly, and I will show you the man who can make all the moeny he wants."

I advise anyone looking to build a reliable and successful form analysis process to focus on class as the primary element.

Some of my views on class were featured in Neils latest edition of Punt to Win, if you haven't already you can read more at:
http://www.propun.com.au/betting_advice.html

Needless to say I focus on class myself and determine it primarily through speed and pace, which with the assistance of good technology and racing intelligence offers me a legitimate and tremendous winning advantage.

Please feel free to pass on your thoughts and comments. Discussing topics like this where we can all learn something from each other is what forums should be about.

[Equine Investor]

On 2002-11-29 13:21, osulldj wrote:
This leads me to believe that the market "underestimates the importance of class" and therefore overestimates the winning chance of horses racing in harder class. Also implied is an overestimation of the impact of weight, particularly decreases in weight when a horse is rising in class.

While simple statistics by themselves cannot offer us any winning advantage, there is no doubt that as an analysis principle, CLASS is KING. As Pitsburgh Phil said, "show me the man who can class horses correctly, and I will show you the man who can make all the moeny he wants."


Very good and thorough research osulldj.
It brings home something I have used and considered very important over the years.

Ranking in order of priority

1. Fitness 45%
2. Class 45%
3. Weight 6%
4. Barrier 4%

In other words a fit class horse can usually carry the weight and overcome a bad barrier given that you have a reasonable jockey on board.

A fit horse of lower class will usually beat an unfit horse of higher class.

(By fit - I mean performing to it's best and medically sound. There are class horses racing prone to sore backs, shin-soreness etc. They are race fit but not medically sound).

<font size=-1>[ This Message was edited by: Equine Investor on 2002-11-29 13:48 ]</font>

[Dr Pangloss]

Once again quality research presented in a most professional manner by all.

I don't mean to be pedantic but the notion of 'Class' got a thorough going over.

Correct me please, but is it not the fact that modern handicappers have relegated 'Class' secondary to the notion of 'Field Stength'. A cursory glance at the Wizard reveals the two are not the same thing.

Indeed, in 'Picking Winners' Part 8, Malcolm Knowles states, "The Field Strength provides an alternative and more accurate way of looking at CLASS change. A change in race class, per se, DOES NOT not give any indication of the difficulty posed. Previous wisdom assumed that a runner going up in class automatically faced a harder task. .....it is not the change in CLASS that needs to be considered, it is the change in RACE QUALITY that needs to be considered."

[osulldj]

Thats right Dr., we can no longer assume that a runner going up or down in class name is facing easier or more harder opposition.

The class changes quoted in my research are based on class or if you like to call them the "race quality" / "field strength" values in the database I use for my racing activities. These values are calculated by examination of the actual starters in each race and there overall record, weighted towards recent performances. So irrespective of the class name of the race the class values and therefore class changes I refer to in the analysis presented are based on the changes in quality of opposition a horse has faced from one run to the next....not the class name.

[Dr Pangloss]

Thanks for the clarification osulldj.

Continue to enjoy your weekly emails thankyou.

[Equine Investor]

Regarding Class and Field Strength:

Absolutely right.

If a horse is engaged in a race with equal class horses it loses all class advantage and you must find other selection criteria.

The advantage is when YOU assess a horse to have a class advantage even though it's form "on paper" is not the best. If you can find horses whose runs are better than what they appear AND have a class advantage, usually you are able to achieve over it's true odds and therein lies the value.

[Every Topic]

if we are to take these ideas to their ultimate conclusion - i.e. weight is essentially irrelevent, class is irrelevent and we should largely consider the strength of the field then I believe we would find that even that is a very difficult thing to accurately detail.
Perhaps such assessment would be, or should be, most accurate in those more isolated areas where the horses are running at the same track each week, under the same conditions, and against each other. Like at Rockhampton or Port Lincoln etc..

The other obvious factor that renders all other factors irrelevent is a horse with exceptional results, but there arent too many of them around.

It is an interesting topic though - and is consistent with my belief that you should seriously head in the opposite direction to that which excites the general racing public.

finally, I personally find the class system used for horse racing very baffling and inconsistent.

The answer would obviously be to award points to every runner in every race to build your own class system - but that would be a hell of a job.
Even if you set out to try to create such a system for one track where the runners met regularly I think it would be hell to devise - perhaps it would be an interesting excercise to embark on collectively.
Pick one track, with races once a week or once a fortnight where the runners are usually the same and try to build a classification system that pinpoints the better horses accurately.

any takers????

see ya
Every Topic

A few extra kilos only matters if there is little between the major chances and you can't split them, other than by weight.

Horses dropping in weight have a weak record because they are rising in class or out of form. Unless they are improving horses capable of the step up, don't back them based on a weight drop.