Calculating house edge for parlays

[CanuckG]

If I want to calculate odds for each leg in a parlay to find the house edge of the entire parlay vs market price how would I go about doing that?

Say I have 4 legs and they're -110 and a competitor has those 4 legs at -105.....how can I calculate the house edge for both?

[dmm]

I would convert each leg into an implied probability, then multiply all those together to get a probability for the entire parlay. Compare that to the implied probability of the offered price of the parlay to see the book edge.

This calculator is handy for quickly converting to implied probability:

https://www.pinnacle.com/en/betting-resources/betting-tools/margin-calculator

Maybe post an example of the parlay you're looking at?

[danmam]

"The Logic of Sports Betting" has a section on how to calculate this. I posted a link to the PDF version of the book here. It's in Part I, page 28 of the PDF.