Quote:
Originally Posted by Mike F
Has anyone seen any retrospective analysis determining whether the odds this site gives actually turn out to be accurate?
The way they fluctuate based on single results, my gut tells me they're somewhere between unreliable and (mathematically) baseless
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Actually, by far, the most mathematically sound.
Instead of predicting, based on models and past events, they run monte carlo simulations of the remaining games.
If you are unfamiliar with those, they simply run future scenarios over and over (millions of times in this case).
There are only so many possible outcomes for any given game. The simulations tally up results of each iteration and the results are counted.
So if the simulation runs one million times, trying different outcomes for each game, and the total number of times that the Flames end up making the playoffs is 800,000, there would be an 80% chance that they make the playoffs. Put another way, based on all the possible ways that the games play out, in 80% of those possible ways or scenarios, the Flames make the playoffs.
No biases. No assuming that a model represents reality in any way, or correlates to anything. Just run outcomes and add them up.
The site does this two ways: random (50-50 chance of any team winning a particular game); and weighted (based on home and away records, etc)
The reason that the odds are swinging wildly now is that there are only a few games left. In order for the Flames to makes the playoffs, the more they win the better. If they win tonight, the odds then include only the scenarios whereby tonight was given a win. If they lose tonight, the odds change to only the scenarios where tonight was given a loss.
Early in the season, if you lose a game, there are still dozens of games to make it up. So odds change only fractionally. But now if you lose, there are only 3 more games to make it up. So the outcome makes a huge difference.
Once it gets down to the last game, the odds include only that game. Imagine a scenario where if you win, you're in and if you lose you're out. That game would have a swing of 100%: up to 100% with a win and down to 0% with a loss.
We are getting closer and closer to that scenario, making each game hugely significant to the final outcome.