Series Comebacks – What are the Odds?

Posted by Ari in Frozen Assets,Uncategorized on April 23, 2009 — 2 Comments

Teams have trailed 3-1 in a series and won 20 of 229 times, 8.7% of the time. Not all 3-1 deficits, however, are created equally. For example, Washington should have a better than 8.7% chance to come back from a 3-1 deficit (thanks Puck Report).

How do you calculate what a team’s chances are to come back from a series deficit (besides looking at their series odds at a sportsbook)?

Let’s use the Washington-Rangers series as an example:

Step 1: Figure out the odds on Washington to win each game.

I recommend Covers. They have the historical odds and results of games dating back to the 1995-1996 season. Also the line for tomorrow’s game is available at any online sportsbook.

Game 5 line: Washington -185

Game 6 line (estimate based on earlier games): Washington -120

Game 7 line (estimate based on earlier games): Washington -195

Step 2: Convert those odds from American into European Style odds.

American odds use + and – to indicate whether a team is a favorite or an underdog. European odds use decimals, and are the same style of odds used in Canadian sports lottery parlay games such as proline. You can find an odds converter here.

Game 5 odds: 1.54

Game 6 odds: 1.83

Game 7 odds: 1.51

Step 3: Multiply the odds together.

Since all three events need to happen in order for the Caps to win the series, odds are determined by multiplying each event.

1.54*1.83*1.51 = 4.26= 1 in 4.26

Step 4: Use the odds converter to determine the percentage chance of an event with odds of 4.26 happening.

4.26 = 23.47%

Summary

Washington’s % Chance to win the series = 1/(odds win G5 * odds win G6 * odds win G7)

OR

1/(1.54*1.83*1.51)= 23.47%.

  • Bob Roberts

    I think the odds for the Caps will change dramatically with a Monday-like win tonight. They need to do what the Ducks did last night and show themselves again what they can do. Confidence can be a very fragile characteristic, and one that defies any connection to ability half the time despite being essential to success.

    BUT — there are no other games tonight (Drew’s scheduling for Gary now?) = spotlight on #8. And is he due?

    I’d love to know the odds of him having a 3 or more point night based on his pattern of busting out after dry spells both on the scoreboard and in the limelight.

    Ironic though that an emotional last-minute/OT hard-fought win would likely result in a 50-50 chance of the Caps going on a roll and winning the series and going quietly in game 6 in my opinion.

    Or the RANGERS could “Do the Ducks” and shut ‘em down. That would mean Rangers-Bruins right? Well, that’d be over fast.

    The math IS elegant, ABC, thanks for it and I’ll take your word for it.

  • http://www.illegalcurve.com Ari

    Caps now have a 70.2% chance of making the next round.