THE POWER RANK

MLS 2011 Playoff Preview

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MLS playoffs
More parity than last year
Red Bulls as spoilers?

The MLS regular season has ended, so now it’s time to look at what The Power Rank can tell us about the playoffs. First, the good news: despite the point differential between conferences, in which Eastern Conference champions Sporting KC (#3) would have finished 5th in the Western Conference, there’s actually quite a bit of parity between the conferences. It worked out this year that 5 teams from each conference qualified for the playoffs, and indeed 9 of the rank’s top 10 made the playoffs. The lone exception was Columbus (#11) edging out the Fire (#10), but both play in the east.

Now for the bad news: the true elite teams, LA (#1) and Seattle (#2), both reside in the west, so fans will not be treated to a championship game pitting these sides against each other. This fact alone reveals the foolishness of the playoff system in a league in which each team plays every other team exactly twice. Because of this format, The Power Rank shows that the first playoff match featuring New York (#6) traveling to FC Dallas (#8) might be one of the most critical postseason matches. If Dallas wins, then the winner of Columbus at Colorado (#9) will play LA in the Western Conference semifinals. The Galaxy would be expected to score 0.8 more goals than the Rapids and a whopping 0.98 goals more than the Crew over a two game playoff. In contrast, KC would be favored by only 0.34 goals over Dallas.

However, if New York wins, the situation would be quite different. The Red Bulls are the most underrated squad by points based on their rank. Because they took the final playoff spot, if they beat Dallas, they will play LA. Even so, the Galaxy should still have a 0.62 goal advantage, but KC could potentially have as much as 0.56 goal edge if the Crew pull off the upset. In this bizarre scenario, the Galaxy end up with only a slight advantage over Sporting KC despite besting them by 16 points during the regular season.

Of course, a possible playoff round against the New York could be the least of LA’s concerns. In the one guaranteed marquee match up of the conference semifinals, Real Salt Lake (#4) will take on the Seattle Sounders (Seattle has a 0.5 goal advantage), setting up what could be one of the best matches of the playoffs if LA ends up winning their semifinal. Home field advantage for the Galaxy could be crucial as they would only edge the Sounders by the slightest margins on a neutral field: 0.01 goals. The Eastern Conference playoffs should still be exciting, as Philly is only a 0.12 favorite versus Houston, while KC would only have a 0.10 goal margin if the Union emerge from their semifinal. However, as has been the case for the past few years, the Western Conference champion will most likely be deserving of the MLS cup.

MLS Blog 19 October 2011

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How to determine
Individual awards?
And do they matter?

As the MLS season enters it’s final week, discussion of season awards begins to dominate the airwaves almost as much as talk of the playoffs.  While the playoffs offer a great spectacle, one has to wonder at the value of individual awards in a team sport.  Of all the player honors MLS hands out, two are clearly the most quantitative: the Golden Boot, going to the player who scores the most goals, and the Goalkeeper of the Year.  Typically, the best keeper judged by some combination of their goals allowed average (GAA) and their number of saves.  The GAA metric is clearly not a function only of the keeper, as a strong defense will prevent shots from even coming his way.  While goals scored and saves made are not perfect measures either, they at least correspond to an action taken by a player (albeit at the discount of actions taken by other players).

So the question is:  does having a player who scores a lot of goals or a keeper who makes a lot of saves correspond to being highly ranked?  To answer that question, we performed a regression of rank versus number of goals scored by the most productive player on a team and the number of saves their keeper made.  For an apples to oranges comparison, we considered the total number of saves rather than that by a single keeper, which is reasonable since most teams rely on just one person between the sticks anyway.  While the correlation coefficient for the number of goals scored by the top goal scorer has a coefficient of 0.023, that number is statistically insignificant (for those who care, the R-squared value is 0.058 and the p-value is 0.33).  What this means is we cannot discern a clear connection between having a one good striker and being highly ranked.  Why?  Well strikers don’t score goals, teams score goals, and the object of soccer is to have the team score a lot, not necessarily an individual.  There is also some evidence from other sports that having one good player actually reduces the value of his teammates (see “Wages of Wins” by David Berri, Martin Schmidt, and Stacey Brook).  So while the Golden Boot is fun for fans, having the winner doesn’t guarantee a successful season.

In contrast, measuring the number of saves by a keeper does have a statistically significant impact (R-squared is 0.34, p-value is 0.011):  it correlates to a lower ranking with a coefficient of -0.009.  The statistics indicate this only accounts for part of a team’s performance, but still this result seems counter-intuitive.  However, the reason is quite clear.  A keeper with a lot of saves is a keeper who gets a lot of opportunities to block shots, hence, someone who’s goal is under a lot of pressure.  So a keeper who saves the average percentage of shots will have more saves if he plays behind a poor defense… but opponents will still score more goals.  Hence, measuring the number of saves is actually a better measurement of the incompetence of the team’s defense rather than the skill of the keeper.

However, we can’t resist suggesting a few players worthy of some accolades.  While the Power Rank can’t determine who generated the most value over the course of the season (yet!), it can suggest places to look.  In addition to providing an absolute rank, a team’s offensive and defensive abilities can be individually assessed.  The top 5 teams in each category are in the tables below, with the value being the expected number of goals scored or conceded against an average opponent. 

Defensively, the LA Galaxy (#1) are best by 0.27 goals, so someone on their defensive side would make sense.  Goalkeepers Donovan Rickets and Josh Saunders essentially split the time this year, and the Galaxy tend not to play with someone in a strictly defensive midfield role.  Therefore center-back Omar Gonzalez seems the best choice of this group as the anchor of their defense.

Meanwhile, the top ranked offense is owned by the Seattle Super Sounders (#2).  In terms of standard statistics, two of their players have distinguished themselves:  Fredy Montero (12 goals, 8 assists) and Mauro Rosales (5 goals, 13 assists).  Because they are both so good, it’s hard to declare one of them as being the most valuable, especially when they are only 0.06 goals better than the next best team, DC United (#12).  While Charlie Davies has scored 11 goals for the Screamin’ Eagles, their side really picked up with the addition of Dwayne Derosario.  The Canadian has scored 12 goals for DC along with 7 assists (he also had 3 goals and 5 assists with Toronto (#18) and New York (#6) this year).  These numbers make him a good choice offensively.  Between the two, Gonzalez would be a better honoree because this has been a defensive season, and LA’s defense is so much better than that of their closest competitor.  However, the MVP is often an “Offensive Player of the Year” award (right, Heisman committee?), and DeRo is the likely recipient if United make the playoffs, while Gonzalez is probably going to receive Defensive Player of the Year honors.

MLS Blog 10/12/11

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The MLS rank
Symmetry is beautiful
But not for Canucks

As we approach the end of the regular season, the MLS Power Rank has taken on a very clear form. Los Angeles (#1) and Seattle (#2) form the elite, while RSL (#3) through Kansas City (#6) round out the upper third. The Sounders and Salt Lake are separated by 0.18 goals, while the above average pack of RSL, Philly (#4), New York (#5), and KC are within a mere 0.05 goals of each other. Of these top sides, all but New York are virtually guaranteed of not only making the playoffs, but a first round bye as well. The Red Bulls have a tough road, as they travel to Kansas City and then finish the season hosting the Union, both of which are in the top third.

A gap of 0.1 goals exists between the above average squads and the 7 teams residing squarely in the middle of the Power Rank. These sides, from last year’s runner-up FC Dallas (#7) through Columbus (#13) are all within 0.07 goals of average (always zero). It is these teams that are currently fighting for their playoff lives, with Dallas, defending champs Colorado (#8), Houston (#10), and Columbus currently in, with Chicago (#9) and DC United (#11) on the bubble. Of this group, only Chivas (#12) has been officially eliminated. With a game in hand and 1 point advantage, Dallas is the clear favorite to emerge from the middle, as two of their last three games are against the lowly Earthquakes (#15) and Whitecaps (#16). DC are also in good shape as they have four matches left, with two against fellow middle teams and two against the lower third. Houston, however, may be in trouble. Their season may depend on whether or not LA decides to field their stars in the last game of the regular season in a bid to break the single season points record.

Once again, a 0.1 differential is found between the bastions of mediocrity and those teams that need some work: the bottom third. In this region, there are two teams slightly better than the rest (a relative situation to be sure): Portland (#14) and San Jose (#15). Of the bottom third, only the Timbers still have a shot at the playoffs, but it will be a challenge. Despite having a game in hand, they finish against teams ranked above them. A difference of 0.2 goals divides the top of the bottom from the true cellar of MLS: Vancouver (#16), New England (#17), and Toronto (#18).

The current MLS rank structure is highly symmetric, with gaps of 0.2 and 0.18 goals separating the exceptionally good and bad teams from the rest. Similarly, differences of 0.1 make the top and bottom thirds distinct from the middle. Of the other sports tracked by The Power Rank, only MLB comes at all close to recovering a structure like this, and then only between the distance between the top 5 clubs and all the rest. This clarity just developed this past week because the top three teams all lost by multi-goal margins. LA dropped 0.06 goals after they lost 2-0 to the Red Bulls in New York, while Seattle decreased by 0.09 goals following a 2-0 defeat at home to the Union. Both victors vaulted above KC in The Power Rank to form the above-average-yet-not-elite. To complete this group, Salt Lake suffered the shock defeat of the weekend, falling 3-0 in Vancouver, who were then the lowest ranked team. Their resulting drop of 0.07 goals confirmed that, this year, they are not a truly elite MLS club.

MLS CONCACAF First Round

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The Champions League
MLS is five for five
More success awaits

CONCACAF Champions League is back, baby! This past week saw the first round of the group stages take place in the 16 team tournament. Each group contains 4 teams, and the top two will advance. Seeding is such that no team from the same country is in the same group, although Canadian and American MLS squads can be (as is the case in Group C with Dallas and Toronto). The tournament has been steadily gaining in importance in North America, and its winner earns a berth in the FIFA Club World Cup. In last year’s tournament, Real Salt Lake made it all the way to the final, taking an important step for MLS internationally. Can the American/Canadian league go further this year?

In any tournament format, it’s always impossible to say, but MLS is off to a flying start after going 5-0-0 in the first round. The format of home and away pairings means each team still has five more matches, so qualification for any club is far from assured. Fortunately, MLS sides are at peak condition being in the middle of their season, while clubs from other countries are still gaining match fitness as their leagues start up. However, the situation will be reversed for the knock-out stages next spring. This makes it important for MLS to get as many teams as possible through the first round.

Of all the wins earned by the MLS teams, there is one clear standout: FC Dallas’ win over Pumas in Mexico City. This marked the first victory ever for an MLS team on Mexican soil in 25 tries. Not only are Pumas one of the top Mexican clubs, but they play in the altitude and smog of Mexico City which gives the US national team so much trouble. While Pumas elected to rest many of their starters in favor of a younger side, after the first 15 minutes Dallas played at a level as high as their competition. Overall, FC Dallas has had an impressive run this season despite the loss of the last year’s MVP, David Ferreira, early in the campaign. Now, having gotten the most difficult match out of the way in the CONCACAF Champions League, they are in good shape to be playing deep into that tournament. The Power Rank can give us some insight about their chances, as well as the other MLS teams.

While The Power Rank doesn’t track foreign soccer leagues (yet!), even if it did, the Mexican and Central American leagues are only just starting so it would need to rely on last season’s data. In addition, it is difficult to compare across different leagues; enough data for a meaningful comparison wouldn’t exist until after the group stages. However, The Power Rank shows that MLS is contributing some of its top sides to the Champions League, with three of the top four (#1 LA, #2 Seattle, and #4 Dallas), and four of the top six (#6 Colorado). The final slot is the Canadian team Toronto FC, which currently resides in the rank’s basement. Of these teams, Seattle and Dallas have a great chance to go deep into the tournament. Both should be able to best the non-Mexican teams in their group, and can expect reinforcements later this year or early next spring for the knock-out stages in the forms of David Ferreira and Steve Zakuani. Additionally, both are young sides, which will hopefully help them recover full fitness earlier in spring should they make it out of the group stages. While LA is clearly the best team in MLS right now and should emerge from their group, question marks surrounding the return of David Beckham and Landon Donovan make it harder to tell how far this older team can go. As for Toronto, well, miracles can happen, even in Canada.

Major League Soccer, Playoff Update

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There’s no phase in sports guaranteed to make physics nerds cringe like “that team has momentum.” When figuring out how a car will drive or an airplane will fly, Newton’s laws tell us what the vehicle’s momentum will be and how we can change it. No equivalent exists in sports, although you wouldn’t know it listening to all the prognosticating that goes on in the media. Just don’t ask anyone to define it. There were worries about Colorado against Columbus because they lost momentum… in the last few minutes of their match against Real Salt Lake. FC Dallas? No chance because they dropped their last two, never mind both were on the road to the only two teams ranked higher than them in the The Power Rank. And let’s not forget Los Angeles Galaxy, top of the table for most of the year but fashionable picks for an early exit against the Seattle Sounders. The only easy pick where the favorite was expected to win was New York over San Jose, but as we’ll see, this also flies counter to the “momentum” argument.

Here at The Power Rank, we know that a sample over a few games isn’t enough to prove anything… but it can be enough to disprove some things. In this case, the question is: can “momentum” at the end of the regular season predict the first playoff results for each team? Well, first we need a definition of momentum, and just in case you think I’m trying to con you, I’ll give you two: points earned over the last 5 games and points earned over the last 10 games. Here you can see the teams ordered by the last 5 games’ momenta.

MLS Teams, Momentum
Both measures give a similar ranking, with only the Rapids leap-frogging LA and Seattle if the last 10 games’ points are considered, and then only by 1 point.

What’s most telling about this ranking is how well it agrees with The Power Rank’s ordering, with only the Sounders and FC Dallas appearing out of place. So you might say ‘ha!’, maybe momentum can beat The Power Rank. Not so fast. A look at the schedule provides a different explanation. In their past 10 games, Seattle was fortunate to only play two playoff teams (Colorado and Salt Lake), thereby racking up points against teams at the bottom of the table. Conversely, Dallas has played six of their last 10 against play-off teams, including LA and Salt Lake on the road. Of their other four games, they picked up three wins and a draw.

Finally, consider the second set of games contributing to the last 10, games 6-10. If we ranked teams based on those 5 games and compared them to The Power Rank, the Sounders come back to earth and LA and Dallas appear as the only aberrations being a bit too low. We’ve already discussed Dallas, but in games 6-10, LA drew the Fire and lost to San Jose, both on the road and both a bit unlucky. So basically, The Power Rank explains most of the trends based on results for the entire season, and the streaks can be attributed to aspects natural to sport: strength of schedule, home field advantage, and of course, a little bit of luck.

So how did the momentum rank do? Well, it did have the Rapids overcoming Columbus, but also New York drawing at San Jose, Seattle getting it done against the Galaxy, and of course, the kings of momentum, Real Salt Lake, should have dominated FC Dallas. It didn’t go down that way, but to be fair, The Power Rank went 2-2 as all home teams were favorites given the ranking. So what’s the difference? The Power Rank is based on what each team earned on the field during the whole season, valuing consistency over finishing the season at home playing bottom table teams. And aside from a few unlucky breaks, we can use The Power Rank to explain almost all the observations about “momentum”. So when it comes time to make your post-season picks, remember your best bet is steady and consistent rather than the current flavor of the week.

This week offers the second legs of the first round playoff matches. Thanks to getting results on the road, the Galaxy and Red Bulls are in good shape to advance to the next round, in line with The Power Rank best estimate. Even though they’re traveling to Columbus, the Rapids are still favored to advance. So what about the matchup predicted by The Power Rank to be the most one-sided? Well, don’t count out the Royal Army of Salt Lake City yet as home field advantage coupled with their top rank gives the defending champs an even chance to advance against a talented Dallas side, especially when considering extra time is played at altitude in beautiful Sandy, Utah. But from the soccer fan’s perspective, the best part is all the ties are only separated by one goal, so we should be in for a weekend of great games. Enjoy!