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What is the formula to translate from betfair's back/lay for exit/remain to percent likelihood of each outcome?
by dzdt 10y ago
What is the formula to translate from betfair's back/lay for exit/remain to percent likelihood of each outcome?
- selectron 10y agoThis site does the calculation: https://electionbettingodds.com/brexit.html https://electionbettingodds.com/brexit.html
- danielvf 10y agoYou can go to the graph on betfair and "invert axis" to see the actual probability.
- joosters 10y agoImplied probability is 100 / odds
- BurningFrog 10y agoIf the odds are 4:1, I'm not sure what that means. 100/4:1 is a notation mystery. 25%?
- danbruc 10y agox:y or x/y means y / (x + y), so 4:1 is 1 / (4 + 1) or 20 %.
- dzdt 10y agoBut what do "back" and "lay" mean?
- danbruc 10y agoBack means you bet on something happening, lay means you bet against it happening.
- corin_ 10y agoBacking is betting on it to happen, laying is being the bookie for somebody else (i.e. betting against it happening). So if something is 4/1 and you back it, you'll win £4 for each £1 you wager. If you lay it, you'll win £1 for each £4 wagered. Betfair exchange is matching up people on both sides of the bet, with a margin of commission in between the back and lay values.