davejb
Dam
The effect of weight isn't linear - a bold statement that is impossible to prove no doubt, but one I'm happy to believe having seen all sorts of fun and games.
The problem with weight, in my view, is that it will affect different horses differently - a 7lb rise might easily blunt the effort of a middle distance runner whilst having a much lesser effect on a sprinter, equally a horse that is 2 hands bigger than a second horse will probably be hampered less than the smaller one by any given weight change. Maybe if we could express it as a fraction of the weight (actually mass of course, physics head on there for a minute) of the horse we might find the curve flattening a bit. (For curve I suspect we should substitute the words 'random wiggle').
In the end we are approximating for the general effect of a given mass on a horse's ability to run fast - carrying no weight at all the horse will have a maximum speed it cannot exceed, we are estimating how much slower it will run with a load on its back.... and that can never be better than an approximation.
You can even argue that horses are big strong creatures and it is silly to imagine 5lb being noticeable - but I think the existence of handicap races and experience of watching races shows that whilst sort of logical and believable in theory it doesn't seem to be borne out in practise.
As some may remember I produced Beyer figures for the all weather tracks last year for a few months, not adjusting for weight carried, and I found the results weren't very good.... to a degree this was probably down to the differences between tracks, which of course makes a fair difference to their effectiveness compared to the US..... here a horse will pogo around from track to track, and the tracks vary quite markedly, while in the US you are looking at a horse that is stabled at a track and runs there, making (I would argue) it much easier to compare one run with another. Towards the end of my experiment I decided that, apart from any other consideration, ignoring weight was not making things any more reliable.
Lengths per second - from the distance of the race (suitably adjusted for rail movements), the standard time for that distance, and the length of a horse you can work out a very accurate lengths per second figure. Unfortunately calculating the standard time for a distance at a track is a bit of an art form to put it mildly, there is endless debate about the length of a horse, and to be honest the actual distance run varies a bit even without rail movements. So, we can compile an accurate figure no problem, except all three of our variables are just that - variable. So lengths per second is also an approximation. For what it's worth Mike's lps figures and the BHA's own figures (available from the BHA site) aren't miles apart, and Mike's have the benefit of being individual to the track and distance whilst the BHA's are 'one size fits all'.
Amateur races won by some poor horse carrying Porky Mc Bladder (14 stone 8 lb in his socks) - call it 10-0 as Mike says, they'll end up with a rating that is a better fit than by rating them 2 stone or whatever higher..... it'll save you backing Porky in the Ascot Gold Cup by mistake.
Dave
The problem with weight, in my view, is that it will affect different horses differently - a 7lb rise might easily blunt the effort of a middle distance runner whilst having a much lesser effect on a sprinter, equally a horse that is 2 hands bigger than a second horse will probably be hampered less than the smaller one by any given weight change. Maybe if we could express it as a fraction of the weight (actually mass of course, physics head on there for a minute) of the horse we might find the curve flattening a bit. (For curve I suspect we should substitute the words 'random wiggle').
In the end we are approximating for the general effect of a given mass on a horse's ability to run fast - carrying no weight at all the horse will have a maximum speed it cannot exceed, we are estimating how much slower it will run with a load on its back.... and that can never be better than an approximation.
You can even argue that horses are big strong creatures and it is silly to imagine 5lb being noticeable - but I think the existence of handicap races and experience of watching races shows that whilst sort of logical and believable in theory it doesn't seem to be borne out in practise.
As some may remember I produced Beyer figures for the all weather tracks last year for a few months, not adjusting for weight carried, and I found the results weren't very good.... to a degree this was probably down to the differences between tracks, which of course makes a fair difference to their effectiveness compared to the US..... here a horse will pogo around from track to track, and the tracks vary quite markedly, while in the US you are looking at a horse that is stabled at a track and runs there, making (I would argue) it much easier to compare one run with another. Towards the end of my experiment I decided that, apart from any other consideration, ignoring weight was not making things any more reliable.
Lengths per second - from the distance of the race (suitably adjusted for rail movements), the standard time for that distance, and the length of a horse you can work out a very accurate lengths per second figure. Unfortunately calculating the standard time for a distance at a track is a bit of an art form to put it mildly, there is endless debate about the length of a horse, and to be honest the actual distance run varies a bit even without rail movements. So, we can compile an accurate figure no problem, except all three of our variables are just that - variable. So lengths per second is also an approximation. For what it's worth Mike's lps figures and the BHA's own figures (available from the BHA site) aren't miles apart, and Mike's have the benefit of being individual to the track and distance whilst the BHA's are 'one size fits all'.
Amateur races won by some poor horse carrying Porky Mc Bladder (14 stone 8 lb in his socks) - call it 10-0 as Mike says, they'll end up with a rating that is a better fit than by rating them 2 stone or whatever higher..... it'll save you backing Porky in the Ascot Gold Cup by mistake.
Dave
