Friday, August 2, 2013

The Ballad of the Bumslayer

During the 2012 football season, Jason Goff (@Jason1Goff), then a producer at Chicago’s 670 The Score but now evening host at Atlanta’s 92.9 The Game invented a term to describe the 7-1 Bears—bumslayers. This chart lists the Bears first eight games and their opponent's final record for 2012:

 Six of the first eight games were against teams that ended the season at .500 or less. An old NFL maxim is teams can only play the teams on their schedule. The Bears lucked out by having the AFC South on their schedule and a Lions team that regressed, and there was considerable fervor in the Chicago area as the Bears began the season 7-1. Forgotten was how the Bears played in achieving this record--the Jacksonville game was tied 3-3 at the half before the Bears scored 38 second half points (an NFL record), and the Carolina game was won on a last-second Robbie Gould field goal. As this transpired, the concept of the bumslayer took hold--the Bears weren't a mighty juggernaut destined to meet the AFC champ in New Orleans but were instead bumslayers, beating bad teams and inflating their record. Jason left Chicago to begin his Atlanta gig in mid-October but the idea took hold as the Bears went 3-5 in the second half to finish the year 10-6 and out of the playoffs and ultimately causing Lovie Smith’s firing. I researched it sporadically last year but did much deeper research over the offseason. This investigates the notion of the bumslayer, whether it is real and what we can learn from it.

To be a bumslayer, bums need to be defined. Particularly in the NFL, bums take time to recognize—for example, no one expected the Lions to backslide the way they did last year, nor were their high expectations for a Colts with a new coach and quarterback. At the beginning of the 2012 season, “experts” very reasonably were calling the Colts bums and the Lions a team to be reckoned with, but as the season progressed it became very obvious that the Lions were the bums. Using end of season records to identify bums is fine but doesn’t work in-season. There are several tools available at the (free!) Pro Football Reference Team Game Finder Play Index tool that can be very useful:
 • Opponent was a playoff team
 • Opponent had a winning record for the year
Not bad, but again, this doesn’t allow for in-season comparisons, and it also doesn’t make clear whether the TEAM itself is a bum. It was when rooting around in this particular feature (which is stunningly informative, by the way), I saw EXACTLY what I was looking for, what was effectively real-time analysis of the relative strength of a team—whether Las Vegas favored a team or saw it as an underdog. Point spread data is included as well, but I wasn’t interested in that as much as the down-and-dirty issue of whom did Vegas view as the better team. I don’t claim to be an expert on sports betting in general or football betting in particular, but I know that point spreads move to induce betting movement. Absent rare occasions, WHICH TEAM is favored doesn’t change. If the Bears play the Packers in Green Bay, chances are Green Bay will be favored—whether by 1, 6.5 or 10 points shifts and moves with new information, but what likely WON’T change is that Green Bay will be favored. As such, I investigated two different but very important questions: 
1. How often do the FAVORED teams WIN (i.e., a bumslayer) 
2. How often do the UNDERDOGS win (i.e., a David defeating Goliath) 
We can illustrate this:

I collected data going back to 1978 (the earliest available) through 2011 (the latest available). I will only show data from 2000-2011 since those are the teams that are most familiar. At the end, I’ll show how coaches performed to see how they performed vs. expectations.

BUMSLAYERS (and bums)

I will introduce this table in segments. This is very simple, team regular season records from 2000-2011. There was one dominant team in that span (New England), several others with sustained excellence (Indianapolis, Pittsburgh, Green Bay and Philadelphia), others with bursts of excellence (Baltimore, San Diego) and the rest being typical—some years were good, some bad and some teams were just bad all the way around.

The columns are:
 FV—games the team was favored 
fW—games the favored team won 
fL—games the favored team lost 
fT—games the favored team tied 
fW%--favored games won percent 
A-Fw—actual games won – times favored 

Using the Patriots as an example, they were favored to win 139 games in this time span. In those 139 games they were 111-28 for a .799 winning percent, which equates to a 13-3 record. They were true bumslayers that won the games they were supposed to win. 

Better teams have more opportunities to be bumslayers, since by definition bum teams are underdogs and can't be bumslayers. Subtracting actual wins from games in which the team was favored shows how much over or under their “potential” teams played. Since this uses week-of point spreads, this is essentially a real-time snapshot of a team's reputation vis a vis their competition. The real standout is the Bears, a middle-of-the-pack team during this span. Their 100 victories were 17 more than expected, with a good number (6) coming during their very surprising 2001 season. What team do many people consider the most overrated team of the 2000s?  The Colts, who won just 1 Super Bowl and a full 20 games fewer than expected. The fact that the Browns and Cardinals won 20 games more than expected is a reflection that they were bad but could pull off an upset once or twice a year--and still have a bad overall record.

This table looks at matters from the opposite perspective, how well teams performed when they were underdogs:

The columns: 
FV—games the team was favored 
UD—games the team was the underdog 
uW—games won as underdog 
uL—games lost as underdog 
uW%--underdog winning percent

Using the Steelers as an example, they were underdogs in 50 games, primarily against Baltimore (10 games), Tennessee and New England (4 each). They did well as the underdog, winning 27 of those 50 games, the best winning percentage in the NFL in this time span, making them the ultimate Davids. But look who was right behind them—New England, who in addition to beating the bums on their schedule were also able to defeat the best teams in the NFL over half the time. When good teams are underdogs, they are playing what could be considered GREAT teams. The Steelers and Patriots were the only two teams in this time span to have records better than .500 against the very best the NFL had to offer.

Consider this table, which compares home vs. road winning percent to favored vs. underdog: 

Irrespective of who is favored, the home team wins around 57% of games, reflecting that for bad teams, playing at home isn’t enough to overcome the fact they’re…well, bad. Favored teams win by a higher margin regardless of whether they’re at home or on the road—that’s what better teams do. 

A common refrain throughout all sports is to win home games and split on the road. In the NFL this translates to going approximately 6-2 at home, 4-4 on the road to end up 10-6, which is usually good enough to make the playoffs (unless you’re the 2012 Bears). I’m not sure that’s the proper way to view a schedule as opposed to defeating those opponents you’re supposed to (i.e., be a bumslayer) at about a 80% clip and go .500 against teams as good or better than you. Every team and fan who goes over the schedule when it comes out and pencils in wins and losses uses this exact analysis, factoring in where the game is played only as a last resort. A bumslayer isn't a term of derision as much as an acknowledgement of how teams make the playoffs--they win the games they're supposed to, and in the modern NFL, teams appear to do that at about a .667 clip.

This table lists all coaches with 100 or more games from 2000-2011 and how they performed both as favorites and as underdogs:

The fact that Dick Jauron, Marty Schottenheimer and Jack del Rio had the most wins over favored teams suggests their teams were not viewed favorably. Norv Turner and Mike Martz are widely considered to have done the least with the talent they had at their disposal, and the numbers support this. 

The NFL is a unique sport in that teams play so many fewer games than the other sports that each one takes on significantly greater import--each football game is worth 10 baseball games. This makes it absolutely essential that the bums on the schedule are dispatched because the difference between the playoffs and a longer offseason is typically one game. The better teams meet or exceed expectations, the also-rans don't. This doesn't suggest a shift in strategy as much as a way to critically review a schedule as fans and get a better understanding of the true path to NFL postseason play.

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