NFL Playoffs: "Hot" Myth or the Bye Week Advantage in Conference Championships?

Andy KontyCorrespondent IIJanuary 17, 2013

Did the Marathon at Mile High sap the Ravens' strength?
Did the Marathon at Mile High sap the Ravens' strength?Doug Pensinger/Getty Images

Four NFL teams meet this weekend to contest the NFC Championship and the AFC Championship, with the winners advancing to contest Super Bowl XLVI.  

Picks, predictions, speculations and forecasts permeate the broadcast airwaves, fill inches of fading newsprint and generate enough heat in online comments to burn even the most calloused Cheetos-dusted fingertips.

Some speculate that this is the year the Atlanta Falcons get over the hump and play to their potential.  Others predict that the San Francisco 49ers aggro defense and electric rookie QB will leave Falcons fans frustrated for another year.

Almost no one is forecasting an upset by the Baltimore Ravens.  Who wants to pick against Bill Belichick and Tom Brady?

The gamblers put their porcine heft behind the 49ers and Patriots.  The 49ers opened as a field-goal favorite, but the gamblers pushed the line up to four as they reconsidered the Falcons' chances of actually playing like a 13-3 team.  The Pats started the week with a double-digit advantage, which has since closed to eight points, perhaps rationalizing that Ray Lewis can keep the game close through sheer force of will.

Others have beaten the player and coaching matchups to a death even the nastiest nag doesn’t deserve. 

But not I, instead I am going to continue flogging my own gimpy pony to see if any of the final four can lay claim to being the “hot” team or, at the very least, some good ol' fashion home cooking.



Hot or Not?

A few weeks ago, I mythologized the irritatingly persistent claim that “hot” teams do better in the NFL playoffs. 

I researched all 22 NFL playoffs since the league expanded the postseason to 12 teams in 1990.  Using the length of a team’s winning streak upon entering the playoffs, the “end-of-season win streak” (ESWS), I showed that a team’s ESWS had no effect on how far that team advanced in the NFL playoffs. 

Applying the ESWS to this year’s playoff participants demonstrates yet again the myth of the “hot” team.

The hottest team entering the playoffs this postseason was the Denver Broncos, who won their last 11 games of the regular season before falling to the Baltimore Ravens in an overtime thriller.

The second hottest team was the Washington Redskins, whose eight game ESWS ended in the Wild Card round with a loss to the third hottest team, the Seattle Seahawks (ESWS=5). 

The Minnesota Vikings won four in a row to end the season and then lost to the team they beat the last week of the season, the Green Bay Packers.

Not much of a playoff run for the hottest teams of the 2012 NFL season.

The final four teams are the antithesis of hot; you could even call them downright chilly.

The Ravens and Falcons both lost their last regular season game while the 49ers (ESWS=1) and Patriots (ESWS=2) were tepid at best. 

The cold front extends beyond the ESWS. If you look at each of the final four teams’ record over the last five regular season games, they were a combined 11-9, a .550 win percentage. 

The final four teams wouldn’t even make the playoffs based on their performances at the end of the regular season.


Bye-Week Advantage

One thing three of the final four teams had going for them in the playoffs was the bye-week advantage.  Since 1990, teams with a bye through the Wild Card Round of the playoffs, won 12 percent more games than home teams in the Wild Card and Conference Championship rounds.

On average, teams with a bye week win 74 percent of the time.  So last week’s divisional round was right on average with three of the four, or 75 percent, of the bye-week teams winning. 

Only the Ravens overcame the bye-week advantage to win a game in which all of the players gave 138 percent (five and a half quarters).  

In terms of the rest and recovery that contributes to the bye-week advantage, the Ravens would seem to be the blown horse in the Conference Championships.  But keep in mind that the Ravens rested six starters in their regular season finale and had two key defensive starters return from injury in the Wild Card Round—a total of eight starters who began the playoffs with more rest and recovery time than other Wild Card teams. 

We’ll see if the marathon at Mile High sapped those extra reserves.



Looking back to the 2005 Pittsburgh Steelers, a bye-week disadvantaged team has won five of the last seven Super Bowls and another lost the biggest game.  Since none of these teams played each other, a bye-week disadvantaged team played in six of the last seven Super Bowls.

This factoid led one of my colleagues to suggest that this is now a “trend” in the NFL.

Is it a trend?  How can we tell if the aberrant pattern is simply an outlier or what us stat geeks call regression toward the mean?  

When should a change in the pattern of the data rightfully be considered a trend?   

A real trend cannot be discerned simply by the pattern of the data unless something fundamental has changed, something that would cause the deviations in the data.  

Since 2005, there have been no changes in the performance of “hot” teams.  The end-of-season win percentage of Super Bowl teams since 2005 is actually slightly worse than the average since 1990.  

Super Bowl teams since 2005 won 22.15 percent of their games in an end-of-season win streak compared to 22.88 percent for all Super Bowl teams since 1990.  In fact, if you remove the obvious ESWS outlier, the 2007 Patriots who won all 16 regular season games, the end-of-season win percentage since 2005 drops to 13.7 percent.

However, there has been a change in the winning percentage of bye-week advantaged teams, which you would expect if lower-seeded teams were making it to the Super Bowl six out of those seven tournaments.  

Bye-week advantaged teams only won 56.3 percent of their home divisional round games since 2005, compared to a 59.4 percent home win percentage in the Wild Card round and a 57.1 percent win percentage for the home team in the Conference Championships.  

Clearly, the home-field advantage in the NFL playoffs has slackened since 2005, as has the bye-week advantage of extra rest and recovery.  

This is just pure speculation on my part, but perhaps NFL teams are better at travelling today than they were ten years ago.  While NFL teams have not travelled on the cheap since face masks acquired more than one bar, sports science has revealed a lot in the last decade about what athletes need in order to recover in time for the next contest.  

Combine that knowledge with the extreme luxury of private planes, advances in game imaging and scouting, and the number of teams playing indoors and perhaps something fundamental has changed in the NFL playoffs. 

The Ravens sure hope so because if the trend holds they will upset the Patriots on Sunday—with an extra day of rest.