IS THE EXACTA OVERLAY CHART CORRECT

[teddy]

HAS ANYONE NOTICED HOW OFTER THE BETS ARE OVERLAYS ON THE OVERLAY CHART THAT IS SUPPOSED TOBE AT A 50% PREMIUM?

EXAMPLE

COMBO 4-1 PAYS $18 FOR 4-5 AND 6-1.... CHART SAYS $16 IS AN OVERLAY

5 OF THE 6 COMBOS WERE OVERLAYED WITH THE 4-5 CHALK ON TOP. IS THIS THE CORRECT WAY TO READ THIS...


WINNING EXACTA WAS 3-1 AND 9-1 FOR $48.00

BY THE CHART THAT WAS A HUGE UNDERLAY.....

[riskman]

HAS ANYONE NOTICED HOW OFTER THE BETS ARE OVERLAYS ON THE OVERLAY CHART THAT IS SUPPOSED TOBE AT A 50% PREMIUM?

EXAMPLE

COMBO 4-1 PAYS $18 FOR 4-5 AND 6-1.... CHART SAYS $16 IS AN OVERLAY

5 OF THE 6 COMBOS WERE OVERLAYED WITH THE 4-5 CHALK ON TOP. IS THIS THE CORRECT WAY TO READ THIS...


WINNING EXACTA WAS 3-1 AND 9-1 FOR $48.00

BY THE CHART THAT WAS A HUGE UNDERLAY.....

First you have to figure what fair pay would be. The 50% premium most likely includes an average track take plus whatever edge you are insisting on ie. 20%.
What did the 50% chart say 3-1/9-1 exacta? Was it $90.

[teddy]

YES IT WAS 90...SO WHAT AM I MISSING...THANKS

[riskman]

YES IT WAS 90...SO WHAT AM I MISSING...THANKS

I am not the best one to explain this situation to you.Lets use a track that has a 20% takeout.
As stated above the first choice is offering odds of 3-1 and the second choice is going off at 9-1. What would be a fair pay exacta? The $2 payouts displayed on the tote include the 20% takeout.
The simple formula I use is:
Bet $2.x odds of first horse X odds of second horse + 1 =
Fair Pay.(the 20% take is excluded here or my bet size would have been 1.60.)
You can also do this with your own odds line if you prefer.
This is sort of crude but so am I :)
Add to this your preferred edge and work around this number. Example:
$2 x(3)x(9 + 1)=Fair Pay x 1.50=$90.(50% premium which is on the high side)
If you are betting more than one combination you have to add in your losing wagers.
Who said this was as easy game!

[Poindexter]

HAS ANYONE NOTICED HOW OFTER THE BETS ARE OVERLAYS ON THE OVERLAY CHART THAT IS SUPPOSED TOBE AT A 50% PREMIUM?

EXAMPLE

COMBO 4-1 PAYS $18 FOR 4-5 AND 6-1.... CHART SAYS $16 IS AN OVERLAY

5 OF THE 6 COMBOS WERE OVERLAYED WITH THE 4-5 CHALK ON TOP. IS THIS THE CORRECT WAY TO READ THIS...


WINNING EXACTA WAS 3-1 AND 9-1 FOR $48.00

BY THE CHART THAT WAS A HUGE UNDERLAY.....


The "exacta overlay chart" is based of of your own line(with no take), not the public odds that factor in the track take. So yes if happened to make the 4 4/5 on your line and the 1 6-1 on your line yes that would be an overlay. The math behind it is fairly simple. Let's take a hypothetical 4 horse field where every horse has an equal chance of winning(in your opinion).
Your line would look like this
1) 3-1
2) 3-1
3)3-1
4)3-1

Fair price on any combo would be $24 for $2 or the "overlay price" assuming you were looking for the 50% premium would be $36. How do you come up with that fairly simple. Horse 1 has a 25% chance of winning. If he wins Horse 2 has a (25% chance out of 75% probabilty of remaining contenders) chance of coming second. so .25 * .33. That equals 1 in 12 or 11-1 fair odds or fiar price of $24 for 2. You can use the same math with any combo on the chart. As mentioned by riskman to calculate fair odds, make your own oddsline. Fair value is odds of top horse x odds of bottom horse+odds ot top horse * $ amount of bet. So in my hypothetical 3*3=9 +3=12. $ amount of $2 makes $24 the fair payout or $36 the "overlay amount".

I never had success with exactas in thoroughbred racing using this approach.
Way back when I used to bet harness racing and did well with it.
I just do not feel it is an accurate model for thoroughbred racing(nature of the racing). But that is the math behind it which makes much sense. Be interested to know how many out there use this model and find it effective for them. It could be I did not handicap well enough to make it work. There is a lot more margin for error in a win overlay rather than in a Exacta overlay.

[BobD]

This approach is good but I try to add one refinement to incorpate those situations where the probability of the horses running second is not equal to a pro rata % of just beating the other runners. For example, if there is an anticipated speed dual where one of the dualers will go on and the other will drop out after losing the dual. They each may be 25% to win but once one goes on the other may be 5% to run second.

[formula_2002]

a odds=4/5
b odds =6-1

their probability =(1/(odds+1))/1.22
the 1.22= an adjustmente for the track tak out, in this case, that calculates to 18% (the pass line in craps is only 1.4%) :)

a prob x (b prob/(1-a prob))= exacta probablility
in this case the proability is 9.45%
or dollars odds of 9.5-1
a $2 exacta bet's fair return would be $21

[Robert Fischer]

And those are the win odds for each horse

And I think the win odds are "fair" for a=4/5 shot

$3.5 - $4

60% chance of winning.

a 6-1 shot that is by far the 2nd best horse in the race...

estimate 1 in 4 chance to run 2nd

.> $17 .

win wager gives you a 60% strike rate

demand high exacta probable

[Robert Fischer]

I butchered this post a little bit,

will try to add some important details and work it a bit more in accurate depth tomorrow. :ThmbUp:


And those are the win odds for each horse

And I think the win odds are "fair" for a=4/5 shot

$3.5 - $4

60% chance of winning.

a 6-1 shot that is by far the 2nd best horse in the race...

estimate 1 in 4 chance to run 2nd

.> $17 .

win wager gives you a 60% strike rate

demand high exacta probable

[teddy]

Well the overlay chart is based on my odds line. So I have to be better than the pubic at analyzing the chart to make it stick... ATR pro will highlight the overlayed exactas for you in great detail. For what they charge that has to be a bargain . I need to get that for daily doubles. Back to exactas, I think they will be few and far between overlayed to actual odds. Especially if the chalk is in the mix.

Regretfully I must add I played Daves method and hit two races in a row last night....flat bet the contenders. Up to 40 pts.