[Ganchrow]

(All comments, criticisms, and suggestions welcome.)

Betting Tools Questions and Comments Thread

[Ganchrow]

Originally Posted by Tchocky

Excuse me if I sound like an idiot but the only ones I understand are the parlay calculator and U.S./Decimal odds converter. Can someone please explain all the other ones?

I'll start off with the Freeplay Value Calculator, which, as its name implies, figures the value of a freeplay bonus based upon betting and hedging at specifioed prices.

For example let's say that a book offers you a $200 freeplay which you bet at +200 and hedge -215, You'd enter $200 into the "Freeplay Size" box, +200 into the "Freeplay Line" box, and -215 into the "Hedge Line" box.

When you click "Calculate" you see that the proper amount for the hedge bet would be $273.02 and your locked-in profit would be $126.98. This means that you would have captured 63.49% of the notional ($200) value of the freeplay.

Now compare that to the same $200 freeplay, bet at -110 (entered into the "Freeplay Line" box) and hedged at +120 (entered into the "Hedge Line" box). After clicking "Calculate" you see that the proper hedge bet under these circumstances would be $82.64 and the locked-in profit would then be $99.17. This means that you would have captured 49.59% of the notional value of freeplay.

The conclusion which could then be drawn from this is that betting a freeplay at +200, and hedging at -215 would be a better usage of the freeplay than betting at -110 and hedging at +120.

[Ganchrow]

Originally Posted by betso

Ganchrow or anyone else, could you please explain to me the usage of the Poisson, Reverse Bet and Round Robin Calculators?

I am familiar with the Poisson distribution for random numbers, but not really how it is being used in a practical betting context. Thanks.

One variable Poisson calculator:
Let's say a book is offering up a prop bet on an event you to believe to be Poisson -- let's say the number of 3-point attempts made by the Knicks in a particular game. The line 15.5o -105 15.5u -115.

You think that the based on historical averages the expected number of Knicks 3pt attempts is actually 15.2. Is th under bet positive expectation?

Solution:

1. Select "One Variable" radio button
2. Enter 15.2 into "Expected Average" text box
3. Enter 15.5 into "Proposition" text box
4. Click "Calculate"
5. We see that the probability of hitting the under ("Less than 15½") is 54.7611%, corresponding to a fair money line of -121.05
6. Since you'd only be laying -115 on the bet your edge would be positive. (How positive? Your edge would be 54.7611% * 100/115 - 45.2389% = 2.3794%)

Two variable Poisson calculator:
Let's say a book is offering up a prop bet on a combination of events, each one of which you to believe to be Poisson and independent -- let's say the number of 3-point attempts made by the Knicks in a particular game versus the number of 3-point attempts made by the Nets in a different game. The line line is Nets -1½ -110, Knicks +1½ -110.

You think that the based on historical averages the expected number of Knicks 3pt attempts is 15.2, and the expected number of Nets 3pt attempts is 17.0. Is Nets -1½ positive expectation?

Solution:

1. Select "Two Variable" radio button
2. Enter 15.2 into "Event A Expectation" text box
3. Enter 1.5 into "Spread" text box
4. Enter 17.0 into "Event B Expectation" text box
5. Click "Calculate"
6. We see that the probability of hitting the Nets -1½ ("A +1½ < B") is 52.0527%, corresponding to a fair money line of -108.56
7. Since you'd have to lay -110 on the bet your edge would be negative. (How negative? Your edge would be 52.0527% * 100/110 - 47.9473% = -0.6267%)

The reverse bet and round robin calculators respectively calculate reverse bet and round-robin risk, max win, and situational win/loss amounts given a notional bet amount, underlying lines, and outcomes.

[Ganchrow]

If you're like me, you frequently reuse many of the same excel sports betting formulas. I've compiled a few related to odds manipulation into this Excel template file as VBA functions. Eventually, I plan to greatly expand on these.

Here are the included functions:

1. US2Dec(USOdds) (usage 1): Converts US-style to decimal. So US2Dec(-110) = 1.909090909
2. US2Dec(range of USOdds) (usage 2): Converts an array or Excel range of US-style odds to decimal parlay odds. So US2Dec(-110,-110) = 3.644628099
3. Dec2US(DecimalOdds): Converts decimal odds to US. So US2Dec(1.909090909) = -110.
4. US2Prob(USOdds) or Dec2Prob(DecimalOdds): Converts from US or decimal odds to probability. So US2Prob(+100) = Dec2Prob(2.0000) = 50%.
5. US2Hold(range of US Odds) or Dec2Hold(range of Decimal Odds): Calculates theoretical hold based on an Excel range of US or decimal odds. So if cells A1 and A2 are both -110, US2Hold(A1:A2) = 4.54545%.
6. {US2Real(range of US Odds)} or {Dec2Real(range of Decimal Odds)}: (array function) Returns an array of zero-vig probabilities based on an Excel range of US or decimal odds. So if cells A1 and A2 are both -110, if B1, B2, and B3 were set to the array formula {=US2Real(A1:A2)}, B1 and B2 would both have the value of 50%, and B3 would have the value of the theoretical hold (4.54545%).
7. ProbUS2Edge(Probability, USOdds) or ProbDec2Edge(Probability, DecimalOdds): Calculates edge based on win probability and US or decimal odds. So ProbUS2Edge(55%,-110) = 5%
8. EdgeUS2Prob(Edge, USOdds) or EdgeDecimal2Prob(Edge, DecimalOdds): Calculates win probability based on edge and US or decimal odds. So ProbUS2Edge(5%,-110) = 55%.
9. ProbEdge2US(Probability, Edge) or ProbEdge2Dec(Probability, Edge): Calculates US or decimal odds based on probability and edge. So ProbEdge2US(55%,5%) = -110.
10. US2Exch(US Odds, Commission) or Dec2Exch(Decimal Odds, Commission): Calculates sportsbook equivalent lines given either US or decimal odds and sports exchange commission.
11. ExchUS2Hold(range of US Odds, Commission) or ExchDec2Hold(range of Decimal Odds, Commission): Calculates theoretical hold including sports betting exchange commissions based on an Excel range of US or decimal odds. So if the values of cells A1 and A2 both equal -102 ExchUS2Holds(A1:A2,2%) would equal the theoretical hold theoretical on the -102/-012 market inclusive of 2% exchange commission (a value of 1.961%).

If you want these functions to be available every time you start Excel you'll need to save the Book.xlt template file in your Excel XLStart directory ("C:\Program Files\Microsoft Office\OFFICE11\XLSTART\" by default for Excel 2003). (If the file already exists you shouldn't overwrite but instead choose a different name as in the next paragraph. Alternatively, if you know what you're doing, you could manually add the Excel VBA functions or module to your preexisting Book.xlt file).

If you want these functions to only be available only by request then save the file under a different name in the XLStart directory. For example, if you saved the file as Ganchrow.xlt, then by clicking "New" on the "File" menu, you'd be able to select the template "Ganchrow" and have all the above functions available.

Download Book.xlt from this thread

[WWTSblows]

By the way, I wanted to say thank you for these. By far, the best single source of calculators for this stuff.

[20Four7]

Why did this stop being a sticky? I'm sure it was for a while.

[cobra_king]

Originally Posted by 20Four7

Why did this stop being a sticky? I'm sure it was for a while.

It's easily accessible on the SBR Live Lines page, on the right hand side, half way down the page!