Bet2Master

At −110, a bettor has to win 52.38% of bets just to finish level. Win exactly half, and a run of 100 such bets at $110 each ends $500 down, even though the record reads 50 wins and 50 losses. That 52.38% is the break even win rate, and it is simply the implied probability of the price read from the bettor's side. This piece shows how to calculate it for any line and why a .500 record is a losing record at standard prices. Concept: the price sets the bar Every price a sportsbook posts implies a probability. Read from the book's side, that number feeds the vig calculation. Read from the bettor's side, the same number answers a more personal question: how often would a bet at this price need to win for the money to come out even over many repetitions? The two readings are identical. The implied probability of a −110 line is 52.38%, and the break even win rate of a −110 bet is 52.38%. Nothing extra has to be calculated. What changes is how the number is used. Formula For ...

A standard −110/−110 line has an overround of 4.76%, but a sportsbook that takes equal money on both sides keeps 4.55% of what was bet, not 4.76%. Both numbers describe the same margin measured against different bases. State revenue reports then publish a third figure, actual hold, which can land far from either in any given month. This piece separates the three. Concept: one margin, three bases Overround is the amount by which a market's implied probabilities exceed 100%. It is measured against probability. Theoretical hold is the share of total money wagered that the book expects to keep if the line is priced as posted. It is measured against handle, the total amount bet. Actual hold , the figure in state revenue reports, is what the book kept after results were settled, divided by handle. It is measured against what actually happened. The first two are fixed by the price. The third depends on outcomes and on which bets customers chose. Formula For each side, implied pr...

A standard American-odds point spread line of -110 on both sides isn't pricing a 50/50 event at even money. It's pricing it at roughly 52.4% implied probability on each side, a total of 104.8%, and that extra 4.8% is the vig, the sportsbook's built-in margin. This piece works through where that number comes from and how to calculate it on any line. Concept: what American odds actually encode American odds express a bet's payout relative to a fixed reference stake. A negative number, such as -110, states how much you must stake to win 100 dollars. A positive number, such as +150, states how much you win on a 100 dollar stake. Both formats encode an implied probability, and that implied probability, not the raw number, is what determines whether a line is fairly priced. Formula: converting American odds to implied probability For a negative line: implied probability equals the absolute value of the odds, divided by the absolute value of the odds plus 100. For a posit...

A baccarat tie bet carries a 14.36% house edge. A blackjack hand played with basic strategy carries roughly 0.40%. That's a 35 fold gap between two bets sitting on the same felt. House edge is the one number that makes bets across completely different games comparable, and most of what gets called "odds" in casual conversation isn't actually that number. Concept: What House Edge Actually Measures House edge is the casino's expected share of every dollar wagered over a large number of bets, not the probability of losing a single hand or spin. A game can have a high probability of winning individual rounds and still carry a meaningful house edge, because the size of the payout on a win matters as much as how often a win happens. Roulette's single number bet wins only 2.7% of the time on a European wheel, yet the house edge is a comparatively low 2.70%, because the payout on that rare win, 35 to 1, is calibrated close to fair odds. A coin flip proposition that...