Monday, March 20, 2017

March 19, 2017

Biggest mover this week was the Columbus Crew with their 2-0 road win over DC United. Toronto and Atlanta also had good weeks. Toronto finishes on top of the Elo ratings, but Toronto, Dallas, and Seattle are close enough in points that I expect the leader to change quite a bit in the coming weeks. Likewise, the bottom five (Chicago, Vancouver, Minnesota, DC United, Salt Lake) are close enough that I'd expect them to flip roles weekly. Salt Lake gets the jeer this week.

Next week is an international weekend and MLS only has 3 games scheduled, so I may or may not update, depending on how interesting those results are.










Monday, March 13, 2017

March 12, 2017

A couple of interesting results from this weekend:

Los Angeles lost their second straight game to start the season, falling to a rating of 1496. This is the first time Los Angeles has been under 1500 since July 8th, 2012, and the worst rating they've had since June 20th, 2012.

Minnesota's massive 42 point drop by way of their 1 to 6 home defeat to Atlanta was the 19th largest single-game rating swing of all time - out of 5030 games played in MLS's history. We don't have to go back very far in time to see the last one to surpass it, though - remember that time Toronto beat NYCFC 5-0 on the road in the playoffs last November?

Minnesota is now ranked dead last on Elo Rating, End of Season Points Predicted, and Monte Carlo simulation. In addition, the change made a huge impact on the strength of West vs. East. The West's average of 1500.90 is the lowest it has been since April 20th, 2013.

Atlanta's outlook received quite a bit of boost due that game as well. They're now predicted to finish 3rd in the East and the Monte Carlo simulator has them at over a 80% chance to make the playoffs.

Three teams remain perfect through week 2: Portland, Houston, and San Jose from the West, and New York Red Bulls from the East.





Monday, March 6, 2017

March 5, 2017

The first week of the 2017 season is in the books, and the biggest winners are the New York Red Bulls, Dallas, Portland, and Houston. All four teams saw more than a 3.5 point increase in their predicted finish to the season. Dallas launches to the top of the Elo Ratings and Seattle slides down to 4th.

































In the Monte Carlo simulator, the Red Bulls and Dallas are front-runners for the Supporters Shield and Seattle's chances took a massive hit.


Monday, February 20, 2017

2017 MLS Season Prediction

Last season I stopped updating this site, though I maintained my rater and made periodic updates to Twitter (@AlanSchrader). This year I'm going to go for a compromise: less frequent updates on a more consistent basis. Maybe every other week or every month or something like that. We'll see what happens as the year plays out.

I also, admittedly, have a tendency to want to post less when Sporting Kansas City is doing poorly. If they are running the table, I'll probably be updating every week.

Anywho, before we get into the numbers I need to talk about a change to the rater I made this offseason. I've been extremely reticent to force Elo ratings to regress to the mean in the offseason. Most other sports Elo raters include this manual adjustment at the end of each season to allow for time off, personnel changes, etc. I've never included it because Elo's system is self-correcting and I've made the case that I like to watch those changes over the course of the season. For the past several seasons, I have noticed that the end-of-season ratings, when used in a Monte Carlo simulation of the following season before a single game has been played, give some extreme results. For instance, last year, Chicago ended the season with a rating of 1384, which after Monte Carlo simulation resulted in a probability of winning the Supporters Shield of 0% (and a chance of making the playoffs at just over 6%). On the other end, Seattle ended the season with a rating of 1629, which after Monte Carlo simulation resulted in a 36% chance of winning the Supporters Shield. While I do believe Seattle have a significantly higher probability of winning than Chicago do, I believe that spread is too extreme on both ends.

After playing around with several different factors in the rating formulas, I decided that the end-of-season regression to the mean was, indeed, the best way to fix this issue. I've retroactively added this to all years and now my rater acts as if I'd been doing this all along. One particular consequence to this revisionist history is every single Elo exhibit I've ever posted to this blog is now wrong. :D

So after redoing past calculations, implementing the end-of-season correction to year-end 2016 ratings, and loading in this season's schedule, we have the following exhibit with which to kick the season off:

































I have to admit these results seem much more reasonable than their predecessors. One thing I wanted to point out: Kansas City, Colorado, Portland, and Minnesota all have nearly identical ratings, and their predicted finish is almost entirely based on strength of schedule. That's a fairly good case study on just how much home/away matchups against certain teams play into these predictions, even when all four of those teams are playing in the same conference and have similar schedules.

Now on to the Monte Carlo simulation:




























These numbers are a lot more reasonable than the previous run (see the deltas for how much these numbers changed). While 5-1 odds for Seattle is probably too high and 667-1 odds for Chicago is probably too low, these are at least in the ballpark now.

Those are all of the words I have for now. If you made it this far, thanks for reading.

Monday, April 25, 2016

April 24, 2016

Los Angeles rises to the top with a convincing win over Salt Lake while Dallas falls to third after a big road loss to Vancouver. Toronto has the biggest gain of the week with 32 after an unexpected (at least in terms of Elo ratings) road win over Montreal.

Los Angeles now leads in terms of pure Elo rating, points prediction, and Monte Carlo estimation. Hard to dispute after their 5-2 thrashing on Saturday.



Monday, April 18, 2016

April 17, 2016

Two wins a piece give Dallas and Colorado the weekly honors, both moving up 36 points. Dallas finally overtakes a struggling Portland team for the highest Elo rating in the league. Colorado, however, still have a lot of room to make up before they are among the elite - their move puts them in 15th overall. Our biggest losers of the week are Kansas City, whose two losses - to Dallas and Colorado, wouldn't ya know - have them plummeting 31 points.

All predictions are coming up Dallas at this point in the season. In addition, the West Conference continues to distance itself from the East. This week saw the Red Bulls lose to both San Jose and Colorado, and Philadelphia lose to Seattle, creating the largest disparity between the two conferences so far this year.





Wednesday, April 13, 2016

April 10, 2016

Biggest positive movers this week are Kansas City and DC United, both grabbing 28 points to the good. Kansas City managed a 2-0 road result against the New York Red Bulls, while DC United managed a 4-0 home win against Vancouver. End of Season predictions change quite a bit this week: FC Dallas falls from 1st to 4th with a draw to San Jose, and Montreal is our new leader after a 2-0 home win over Columbus. Also of note: 2nd, 3rd, and 4th place are within 0.3 predicted points of each other, so there isn't much separating the leaders right now.

The Monte Carlo method is also putting Montreal on top, with Kansas City trailing closely.