Final odds to index race competiveness

[TrifectaMike]

I believe that we can all agree that the final odds "contain" ( is a refection of) all known information about a particular race. Threfore, would it not be an unreasonable assumption that the level of race competiveness can be inferred by the final tote odds?

For our purpose, let's view the pari-mutuel system as one "grand" bookmaker and odds-setter. Let me give this entity a human characteristic and call it, "The Man".

"The Man" is very sharp indeed and quite good at his job. He reasons that if he had a race with with an infinite number of horses with an equal amount of money bet on each horse, he would define this as a perfectly competitive race. If on the other hand all the money were bet on a single horse, he would define this as the "most" uncompetitive race. Obviously theses are two extremes and highy unlikely conditions, but this will give him some bounds to work from.

"The Man" fiddles somewhat with the odds and draws some conclusions.

1. A race with a heavy favorite should be classified as less competitive.
2. A race with more balanced odds should be classified as more competitive.
3. Maybe I can use this classification for future reference.

The more "The Man" thinks about it, the more he likes the concept. It is not based on actual race outcomes (not race class, not pace of race nor time of race). It is based on the final odds distributions.

After a bit of pencil scratching he settles on the following formula for the classification:

sum {1/[O(i) +1]^2}/N

O(i) Odds of the ith horse
N Number of entries

The larger the value, the more uncompetitive the race.

Mike (Dr Beav)

[DeltaLover]

Originally Posted by TrifectaMike

I believe that we can all agree that the final odds "contain" ( is a refection of) all known information about a particular race.

I believe that we can all agree that the final odds "contain" ( is a refection of) all known information about a particular race.

I totally disagree.

'All known information' about a race is a composite of the public and insider domain.

The proportion of these two sources of information is impossible to be known before or after the race.

In other words a betting stable will have a totally different impact to the final odds than a non betting one.

Even more than this someone can make a point about the various derivatives of the 'public' info .

A good handicapper can detect a betting angle that generates an huge overlay while his bankroll does not allow him to bet enough to correct the value leaving some of it unexploited....

[Saratoga_Mike]

DL - excellent post.

[Some_One]

Originally Posted by TrifectaMike

I believe that we can all agree that the final odds "contain" ( is a refection of) all known information about a particular race. Threfore, would it not be an unreasonable assumption that the level of race competiveness can be inferred by the final tote odds?

For our purpose, let's view the pari-mutuel system as one "grand" bookmaker and odds-setter. Let me give this entity a human characteristic and call it, "The Man".

"The Man" is very sharp indeed and quite good at his job. He reasons that if he had a race with with an infinite number of horses with an equal amount of money bet on each horse, he would define this as a perfectly competitive race. If on the other hand all the money were bet on a single horse, he would define this as the "most" uncompetitive race. Obviously theses are two extremes and highy unlikely conditions, but this will give him some bounds to work from.

"The Man" fiddles somewhat with the odds and draws some conclusions.

1. A race with a heavy favorite should be classified as less competitive.
2. A race with more balanced odds should be classified as more competitive.
3. Maybe I can use this classification for future reference.

The more "The Man" thinks about it, the more he likes the concept. It is not based on actual race outcomes (not race class, not pace of race nor time of race). It is based on the final odds distributions.

After a bit of pencil scratching he settles on the following formula for the classification:

sum {1/[O(i) +1]^2}/N

O(i) Odds of the ith horse
N Number of entries

The larger the value, the more uncompetitive the race.

Mike (Dr Beav)

I think the problem with the assumption is that different people have different infomation, a morning line based on Beyer figs will be different then those using HDW, Bris or Thorograph. Then you have the pedigree, jockey, trainer info. It's what makes this game so great, so many ways to play.

[TrifectaMike]

Originally Posted by DeltaLover

I believe that we can all agree that the final odds "contain" ( is a refection of) all known information about a particular race.

I totally disagree.

'All known information' about a race is a composite of the public and insider domain. This is true, but irrelevant to the metric.

The proportion of these two sources of information is impossible to be known before or after the race. This is not true, but also irrelevant to the metric.

In other words a betting stable will have a totally different impact to the final odds than a non betting one. Irrelevant.. The final odds are simply just that final odds by definition. I don't get the point.

Even more than this someone can make a point about the various derivatives of the 'public' info . This is in conflict with your first point.

A good handicapper can detect a betting angle that generates an huge overlay while his bankroll does not allow him to bet enough to correct the value leaving some of it unexploited.... This is true, but also irrelevant to the metric.

Help me out, becuase I seriously don't get what your are attempting to say in relation to this thread.

Mike (Dr Beav)

[TrifectaMike]

Originally Posted by Some_One

I think the problem with the assumption is that different people have different infomation, a morning line based on Beyer figs will be different then those using HDW, Bris or Thorograph. Then you have the pedigree, jockey, trainer info. It's what makes this game so great, so many ways to play.

FINAL Tote-Odds are FINAL tote-Odds!

Mike (Dr Beav)

[GameTheory]

Originally Posted by TrifectaMike

Help me out, becuase I seriously don't get what your are attempting to say in relation to this thread.

I think something along the lines of "the final odds mean something different in each race depending on who bet that race and what info they were using and how much money they had, and since you can't tell what the mix of factors and money was that contributed to the final odds for each race, it is basically a garbage statistic, and so therefore will any metric be that is based on it, or at least the one you are proposing." That's my guess, anyway...

[ALL CIRCUITS GO]

Originally Posted by TrifectaMike

I believe that we can all agree that the final odds "contain" ( is a refection of) all known information about a particular race. Threfore, would it not be an unreasonable assumption that the level of race competiveness can be inferred by the final tote odds?

For our purpose, let's view the pari-mutuel system as one "grand" bookmaker and odds-setter. Let me give this entity a human characteristic and call it, "The Man".

"The Man" is very sharp indeed and quite good at his job. He reasons that if he had a race with with an infinite number of horses with an equal amount of money bet on each horse, he would define this as a perfectly competitive race. If on the other hand all the money were bet on a single horse, he would define this as the "most" uncompetitive race. Obviously theses are two extremes and highy unlikely conditions, but this will give him some bounds to work from.

"The Man" fiddles somewhat with the odds and draws some conclusions.

1. A race with a heavy favorite should be classified as less competitive.
2. A race with more balanced odds should be classified as more competitive.
3. Maybe I can use this classification for future reference.

The more "The Man" thinks about it, the more he likes the concept. It is not based on actual race outcomes (not race class, not pace of race nor time of race). It is based on the final odds distributions.

After a bit of pencil scratching he settles on the following formula for the classification:

sum {1/[O(i) +1]^2}/N

O(i) Odds of the ith horse
N Number of entries

The larger the value, the more uncompetitive the race.

Mike (Dr Beav)

----


My math is not great, so can you give an example of how the formula you settled on looks when there is a heavy favorite versus when there is not a heavy favorite? I can't figure out where that info is taken into account. thanks.

[TrifectaMike]

Originally Posted by GameTheory

I think something along the lines of "the final odds mean something different in each race depending on who bet that race and what info they were using and how much money they had, and since you can't tell what the mix of factors and money was that contributed to the final odds for each race, it is basically a garbage statistic, and so therefore will any metric be that is based on it, or at least the one you are proposing." That's my guess, anyway...

The final odds are a garbage statistic. REALLY?

Mike (Dr Beav)

[GameTheory]

Originally Posted by TrifectaMike

The final odds are a garbage statistic. REALLY?

Mike (Dr Beav)

A) I didn't say I agreed with it, I was just trying to put out there what I think others are likely thinking.

B) I followed up that bit with something about "at least in regard to the metric you are proposing", i.e. your metric seems to make the assumption that a horse that (for example) is 2-1 in a five horse race is "equal" to any other 2-1 horse in some other five horse race, but of course that 2-1 is determined by the betting, and the betting in those two races was done by a totally different (more or less) group of people for totally different (more or less) reasons, and those people had totally different (more or less) amounts of money to play with, so that equality assumption needs some justification, doesn't it?

[Dave Schwartz]

Mike,

So, if I am understanding what you are saying, you are building a metric which demonstrates (theoretically) the competitiveness of a race as viewed by the current state of the tote board.

Yes?


Dave

[ALL CIRCUITS GO]

thats what I am trying to understand..

given equal fields of 5 horses, how do you adjust the metric to show that in one race the 2-1 favorite faced horses with odds of 4-1, 5-1, 6-1, and 7-1 while in the other race the 2-1 faced horses with odds of 2.5-1, 3-1, 3.5-1, and 3.75-1; and how is that shown?

maybe its there and I don't see/understand the maths.

also, how do you account for the fact that the two races come up 'competitive', yet in one race the favorite finished 1st and in the other the favorite finished 5th. Was the public wrong? Or was it the horse?

looks like a starting point, but where can it lead?

[GameTheory]

Of course the basic idea is nothing new -- I think a few of the programs out there have an entropy stat that is similar (not sure if they actually use Shannon's entropy formula or not, but basic idea is the same). Doesn't HTR have a volatility index based on the ML which is basically entropy? (Pre-race stat).

[TrifectaMike]

Originally Posted by GameTheory

A) I didn't say I agreed with it, I was just trying to put out there what I think others are likely thinking.

B) I followed up that bit with something about "at least in regard to the metric you are proposing", i.e. your metric seems to make the assumption that a horse that (for example) is 2-1 in a five horse race is "equal" to any other 2-1 horse in some other five horse race, but of course that 2-1 is determined by the betting, and the betting in those two races was done by a totally different (more or less) group of people for totally different (more or less) reasons, and those people had totally different (more or less) amounts of money to play with, so that equality assumption needs some justification, doesn't it?

That is NOT what the metric is saying!

Mike (Dr Beav)

[TrifectaMike]

Originally Posted by ALL CIRCUITS GO

thats what I am trying to understand..

given equal fields of 5 horses, how do you adjust the metric to show that in one race the 2-1 favorite faced horses with odds of 4-1, 5-1, 6-1, and 7-1 while in the other race the 2-1 faced horses with odds of 2.5-1, 3-1, 3.5-1, and 3.75-1; and how is that shown?

maybe its there and I don't see/understand the maths.

also, how do you account for the fact that the two races come up 'competitive', yet in one race the favorite finished 1st and in the other the favorite finished 5th. Was the public wrong? Or was it the horse?

looks like a starting point, but where can it lead?

The metric is measuring what you said and I bolded it.

Mike (Dr Beav)