2012 Turnover Analysis – Updated Thru Northwestern

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Preseason Prediction (Not Happening!): Michigan will end the year with a +8 Turnover Margin (TOM) or better (2011 was +7). The prediction for TOM for M for this year is based on the prediction that M will be a very good team again this year and is not based on the actual TOM of last year. (Very good teams will have a TOM of +5 or better.) Turnover Margin for the year is currently – 5.

Whew!: A spectacular last second catch by Roundtree and thoughts of brunettes by Gibbons saved Michigan from a second loss this year due to turnovers (ND was the one). At the end of regulation, turnovers had cost Michigan 8.1 expected points!

Michigan Football: Michigan had 30 pass attempts and 32 rushing attempts for a 51% run play percentage. This dropped M to a 62% run play percentage overall (ranked #16). NW is ranked #112 in passing defense and #28 in rushing defense – so, yeah. In 2011 M ranked #11 at 65% run play %.

imageSynopsis for Turnovers: Here is the overall summary for all games by player (data in yellow was affected by this week's game).

Black forced a fumble that was recovered Bolden. Gardner threw the one pick that drew a collective SHIT from all of us. Michigan now has 16 different players that have either forced a fumble, recovered a fumble, or intercepted a pass.

For giveaways, Michigan is ranked #15 in fumbles and #9 in fumbles lost but remains at #124 in interceptions thrown %. Even if you take out the 4 interceptions thrown by Bellomy, M would still be ranked #123 in interceptions thrown %. The good news is that in B1G games, Robinson/Gardner have been much better with an interception % of 2.6% (which would be ranked #52).

For takeaways, M is ranked #82 in forced fumbles, #66 in fumbles recovered, #85 in takeaway fumble recovery %, and #83 in interceptions.

imageSynopsis for Expected Point (EP) Analysis: Turnovers resulted in a net of 8.1 expected points benefitting Northwestern.

The folks at Football Outsiders – FEI are also doing weekly "Revisionist Box Scores" that strips out TOs, Special Teams, and Field Position. FEI calculates the value generated by each drive and then lost on the drive up until the turnover, as if the drive had concluded at that spot on the field. Thru Week #11, FEI has 16% of games where TOs were significant.

(See the Section on Gory Details below for how the adjustment for Expected Points (EP) is calculated.)

imageNational Rankings: All rankings include games between two FBS teams ONLY and are from TeamRankings except for forced fumbles which is from CFBStats. imageThe four columns with *** show the best correlation to offense and defense (per Advanced NFL stats).

The Gory Details

Expected Point (EP) Analysis: Basically, the probability of scoring depends on the line of scrimmage for the offense. Therefore, the impact of a TO also depends on the yard line where the TO is lost and the yard line where the TO is gained. Each turnover may result in an immediate lost opportunity for the team committing the TO and a potential gain in field position by the opponent. Both of these components can vary dramatically based upon the down when the TO occurred, the yards the TO is returned, and whether the TO was a fumble or an interception.

Here are the details for the game.

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The analysis is a bit tricky because: (A) the TO may directly result in lost EP for the offense but (B) only modifies the EP for the team gaining the TO because the team gaining the TO would have gotten another possession even without the TO (due to a punt, KO after a TD, KO after a field goal, etc.). The Net EP Gain must take into account the potential EP gain without the TO. The EP gain without the turnover is based on where the field position would have been for the next possession if the TO had not occurred.

image_thumb10_thumb_thumb_thumb_thum[1]

image_thumb17_thumb_thumb_thumb_thum[1]The expected point calculations are based on data from Brian Fremeau at BCFToys (he also posts at Football Outsiders). Fremeau's data reflects all offensive possessions played in 2007-2010 FBS vs. FBS games. I "smoothed" the actual data.

Here is a summary of the smoothed expected points.

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