FanPost

Week Six ARI@SF – a look at Expected Points Added (EPA) and Win Probability Added (WPA)

Expected points added and win probability added (EPA and WPA) have been tallied for the 49ers-Texans game. I will go through the performances of our offensive skill players that got touches in the game, along with some D/ST notes.


So, as a refresher, according to AdvancedNFLStats.com EPA is


Expected Points Added (EPA) – The difference between the Expected Points (EP) at the start of a play and the EP at the end of they play. EPA is the measure of a play’s impact on the score of the game. An individual player’s EPA is the sum of the EPA of the plays in which that player was directly involved. Being directly involved is defined as an offensive player who ran, threw, or kicked the ball, was targeted by a pass, or flagged for a penalty.

I wish I had play-by-play WPA, but I don't, but WPA is


Win Probability Added (WPA) – The difference between a team’s Win Probability (WP) at the start of a play and the WP at the end of the play. WPA is the measure of a play’s impact on the outcome of a game. An individual player’s WPA is the sum of the WPA of the plays in which that player was directly involved. Being directly involved is defined as an offensive player who ran, threw, or kicked the ball, was targeted by a pass, or flagged for a penalty. Defensive players are credited for WPA when they tackle or sack the ball carrier, are credited with an assisted tackle or sack, cause a fumble, defend a pass, or are flagged for a penalty.

As always, we’ll begin with the most important position on the field, Quarterback. Kaepernick had an average week against a very good defense. Excluding his one kneel-down, Kaepernick had a negative EPA for the game: -2.0. On a per play basis, it was -0.06. Combined, they two turnovers cost Kaepernick 10.4 in EPA. What’s interesting is that the fumble was nearly as costly as the interception because the INT was so deep in ARI territory that it put the ARI offense in a terrible position. In contrast, the fumble put ARI only ~10 yards out of field goal range. Excluding the turnovers, Kap had an EPA of 8.4 and an EPA/p of 0.262. Kap’s 4 ‘carries’ – a sack, a bad snap, and two rushes excluding the fumble-turnover – netted an EPA of -2.5, -.62/play. Kaepernick’s WPA was 0.05, according to AdvancedNFLstats.com. ESPN’s QBR, which is based on EPA and adjusted with some proprietary methods, gave Kaepernick a 50.3 QBR for the game – 50 is average. Note that this is unadjusted for the performance of the opposing defense, but that’s OK because it’s so early in the season that it’s difficult to adjust. So, average game.

Quarter Time Down ToGo Location Detail EPA
1 12:54 1 10 SFO 19 Colin Kaepernick pass incomplete deep middle intended for Anquan Boldin -0.54
1 12:45 2 10 SFO 19 Colin Kaepernick pass complete short left to Vernon Davis for 6 yards (tackle by Karlos Dansby) 0.1
1 12:05 3 4 SFO 25 Colin Kaepernick sacked by Karlos Dansby and Calais Campbell for -7 yards -1.95
1 10:37 1 7 CRD 7 Colin Kaepernick pass incomplete short right intended for Anquan Boldin (defended by Patrick Peterson) -0.84
1 9:50 3 7 CRD 7 Colin Kaepernick pass incomplete short left intended for Vernon Davis (defended by Yeremiah Bell) -0.84
1 7:49 2 9 SFO 33 Colin Kaepernick pass incomplete short middle intended for Anquan Boldin (defended by Tyrann Mathieu) -0.69
1 7:45 3 9 SFO 33 Colin Kaepernick pass complete short left to Vernon Davis for 3 yards (tackle by Yeremiah Bell) -0.95
1 4:39 3 7 CRD 8 Colin Kaepernick pass incomplete short right intended for Jonathan Baldwin (defended by Daryl Washington) -0.8
1 2:18 2 7 SFO 35 Colin Kaepernick pass complete short right to Anthony Dixon for 3 yards (tackle by Darnell Dockett) -0.3
1 1:10 1 10 SFO 43 Colin Kaepernick pass complete short left to Vernon Davis for 26 yards (tackle by Patrick Peterson) 1.71
2 14:22 1 10 CRD 17 Colin Kaepernick pass complete short right to Vance McDonald for 7 yards (tackle by Tyrann Mathieu) 0.66
2 13:24 2 18 CRD 25 Colin Kaepernick right guard for 17 yards (tackle by Karlos Dansby) 1.99
2 11:13 2 2 CRD 2 Colin Kaepernick pass incomplete short right intended for Bruce Miller is intercepted by Yeremiah Bell at ARI-1 -5.34
2 8:41 1 10 SFO 39 Colin Kaepernick pass complete deep middle to Vernon Davis for 61 yards. TOUCHDOWN 5.47
2 6:57 1 10 SFO 22 Colin Kaepernick pass incomplete short left intended for Vernon Davis (defended by Karlos Dansby) -0.54
2 6:24 1 10 SFO 39 Colin Kaepernick pass complete deep left to Vernon Davis for 28 yards (tackle by Jerraud Powers) 1.85
2 5:50 1 10 CRD 33 Colin Kaepernick pass incomplete short right intended for Marlon Moore -0.54
2 5:44 3 15 CRD 38 Colin Kaepernick pass incomplete short right intended for Kendall Hunter -0.77
2 2:54 1 10 SFO 42 Colin Kaepernick pass complete short middle to Bruce Miller for 11 yards (tackle by Karlos Dansby) 0.73
2 2:22 1 10 CRD 47 Colin Kaepernick pass complete short right to Vernon Davis for 12 yards (tackle by Jerraud Powers) 0.79
2 2:00 1 10 CRD 35 Colin Kaepernick pass complete deep right to Vernon Davis for 35 yards touchdown 3.75
2 1:30 1 10 SFO 27 Colin Kaepernick pass incomplete short left intended for Anquan Boldin (defended by Patrick Peterson) -0.54
2 1:26 2 10 SFO 27 Colin Kaepernick pass complete short right to Anquan Boldin for 15 yards 1.53
2 1:20 1 10 SFO 42 Colin Kaepernick pass complete short right to Jonathan Baldwin for 9 yards (tackle by Jerraud Powers) 0.67
2 1:14 2 1 CRD 49 Colin Kaepernick sacked by Darnell Dockett for -7 yards. Colin Kaepernick fumbles (forced by Darnell Dockett) recovered by Daryl Washington at SFO-44 (tackle by Alex Boone) -5.05
2 0:28 1 10 SFO 15 Colin Kaepernick kneels for -1 yards -0.6
3 13:38 3 3 SFO 13 Colin Kaepernick left end for 2 yards (tackle by Tyrann Mathieu) -1.84
3 7:25 1 10 CRD 42 Colin Kaepernick for no gain. Colin Kaepernick fumbles recovered by Colin Kaepernick at ARI-43 -0.68
3 6:40 2 11 CRD 43 Colin Kaepernick pass incomplete short right intended for Vernon Davis (defended by Karlos Dansby) -0.69
3 1:07 1 10 SFO 11 Colin Kaepernick pass complete short right to Anquan Boldin for 7 yards (tackle by Patrick Peterson) 0.37
4 15:00 3 2 SFO 19 Colin Kaepernick pass complete short right to Anquan Boldin for 6 yards (tackle by Patrick Peterson) 1.09
4 13:50 2 7 SFO 28 Colin Kaepernick pass incomplete short right intended for Anquan Boldin -0.7
4 13:44 3 7 SFO 28 Colin Kaepernick pass complete short middle to Kyle Williams for 14 yards (tackle by Rashad Johnson) 1.96
4 11:44 2 10 CRD 43 Colin Kaepernick pass incomplete short right intended for Kyle Williams (defended by Daryl Washington) -0.69
4 11:41 3 10 CRD 43 Colin Kaepernick pass complete short middle to Vernon Davis for 9 yards (tackle by Yeremiah Bell) -0.39

Time to move on to our wide receivers.



Vernon Davis – netted an EPA of 9.6 on 12 plays, including a false start penalty. Excluding the false start, 10.25 on 11 targets. While this sounds amazing, he actually had a better week last week (!) with an EPA of 8 ½ on 6 targets (1.52 EPA/p). So, he’s on quite the hot streak. He had a crazy 0.34 WPA.



Anquan Boldin - -0.32 on 8 plays, -0.04 EPA/p. 3 for 8, 28 yards; Boldin was covered by Peterson with help from the Honey Badger – he had a difficult task. He had a much better week last week.



Bruce Miller – Receiving EPA of -4.6 due to the interception. Two key carries for 2.2 EPA.



Kyle Williams - two targets, EPA of 1.27. 0.635/play. Also had +1.41 EPA on four kickoffs beyond what a touchback would have yielded – can’t really calculate punt returns well.


Jon Baldwin – two targets, EPA of -0.13.


Vance McDonald – one target, EPA of .66.



Running Backs



Frank Gore – 25 plays, EPA of 0.54. 0.0216/play. That includes late hit on Gore – without that, his EPA drops to -1.12. Arizona set out to stop Gore, and they failed.



Kendall Hunter - 5 plays, -1.21 EPA, -.258/play. Note that this play includes the clipping call after Hunter took a big loss on a run. You can exclude that play, and his performance is the exact opposite: EPA of 1, 0.25 EPA/play.



LaMichael James – Healthy Scratch



Anthony Dixon - -2.36 EPA for -.56/play. Most of this was running the clock out into a brick wall. not much to talk about.



Defense & Special Teams



Andy Lee – (!) Monster punting day. 6 punts, EPA of 2.53. 0.42/play. wow.



PLAYER OF THE GAME: Eric Reid! 5 plays against reid, -11.3 EPA for Arizona! -2.26/play. Wow. If we give Patrick Willis 50% credit for the fumble, he still has an EPA of 10 on 5 plays. AdvancedNFLstats.com says he had a WPA of 0.37.



Carlos Rogers had 9 action plays, EPA of -4.4. I discounted the down field tackle of Golden.



Corey Lemonier - -5.25 EPA; -1.3175 EPA/play. wow! -3.04 EPA and 0.76/play if Bowman gets 50% of the credit for the fumble.



Brown covered Fitz for most of the game, and gave up a lot of EPA


Willis, Bowman, and Whitner also had excellent games, but it’s hard to quantify their impact at this point.


SUMMARY: The Defense won this game – the offense did enough to win; Eric Reid should be in rookie of the year consideration…and Lemonier has almost made me forget about Aldon (!). Again, our passing game desperately needs Crabtree or Manningham back. We are forcing defenses to take away Boldin OR Davis – and so far only Seattle was able to take away both. If defenses are going to key on those two guys, we need someone else that can separate.

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