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Quantifying the Explosive Play

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We've heard a lot of analysts talk about 'the explosive play', and why its so important to the NFL these days, and how Colin Kaepernick has far more of them than Alex Smith. Smith has 23 plays of 20+ yards (1 run) out of 267 passes, sacks, and runs. Kaepernick has 13 plays of 20 or more yards out of 111 passes, sacks, and runs. On plays of 25 yards or more, Smith has 11 and Kaepernick has 9. On plays of 30+ yards, Smith has 6 and Kaep has 7.

This is despite that fact that Smith has 2.5x more plays than Smith -- discussion closed, right? wrong.

Question: which quarterback is more dependent on the 'big play' for yards? The answer is that they're the same!

On plays that didn't result in a turnover (more later), Alex Smith averaged 6.64 yards per play (pass/run/sack). If you throw out the top 5% of his non-turnover plays, this drops to 5.2 yards per play (pass/run/sack). In other words, his biggest plays are responsible for 22% of his yards.

Let's turn to Kaepernick. On plays that didn't result in a turnover, Colin Kaepernick averaged 7.89 yards per play (pass/run/sack). If you throw out the top 5% of his non-turnover plays, this drops to 6.08 yards per play. In other words, his biggest plats are responsible for 23% of his yards.

Its basically the same (I had to Split a Kaepernick pass in half to fit it within the top 5%). If I threw out the top 25% of plays, the results don't change (much) - Smith got 62.5% of his non-turnover play yardage from the top 1/4th of his plays, while Kaep got 63.5%.

50.5% of Smith's plays resulted in 5 or more yards. Kaepernick, 49.5%. 63.7% of Smith's plays resulted in positive yardage. Kaep - 65.5%.

Tack on the fact that Smith was 25% more likely to commit a turnover than Kaepernick, and 60% more likely to be sacked than Kaepernick.

*** Simply put, Kaepernick has been better than Smith at everything, on all types of plays. Put any idea that he's just more likely to complete a big pass or run downfield out of your head completely.
I wanted to add a note about expected points added. Excluding 'no play' penalties, Alex Smith averaged 0.134 added expected points per play, or 35.82 in total. Colin Kaepernick is averaging .277 expected points added per play, or 30.7 in total. That's DOUBLE.

Twice as good.

In addition to having double the EPA/play, Kaep's EPA/play is far, far less volatile. Smith's coefficient of Variation (CV) for EPA/play is double Kaepernick's.
[ Edited by nickbradley on Nov 30, 2012 at 1:15 PM ]
Nickbradley, thanks for another good statistics based post. I know it takes some time and effort to crunch those numbers but I think these type of posts are good for shedding light on certain overlook facts and also serve for good chat fodder. I also know you never imply that statistics is the means-all for analyzing players but I agree that it can help put certain hard-to-quantify things into better perspective.

On a "non-statistical" note, I think the most impressive thing about Kaepernick so far is his ability to extend plays in the pocket. I know the media constantly talk about his legs and his arm. But in re-watching the games several times (for good fun, try watching his games with the imagination that it's Alex Smith behind center instead of him), the first thing that jumps out about Kaepernick is his ability to avoid pressure and extend plays. I think that alone makes him stand out vs Alex and I think is one of the main reasons why Harbaugh is so high on him. And I think it's one of the reasons why you'll see slightly more big plays, less sacks, and overall improvement vs Smith.
[ Edited by Otohns on Nov 30, 2012 at 1:22 PM ]
Originally posted by Otohns:
Nickbradley, thanks for another good statistics based post. I know it takes some time and effort to crunch those numbers but I think these type of posts are good for shedding light on certain overlook facts and also serve for good chat fodder. I also know you never imply that statistics is the means-all for analyzing players but I agree that it can help put certain hard-to-quantify things into better perspective.

On a "non-statistical" note, I think the most impressive thing about Kaepernick so far is his ability to extend plays in the pocket. I know the media constantly talk about his legs and his arm. But in re-watching the games several times (for good fun, try watching his games with the imagination that it's Alex Smith behind center instead of him), the first thing that jumps out about Kaepernick is his ability to avoid pressure and extend plays. I think that alone makes him stand out vs Alex and I think is one of the main reasons why Harbaugh is so high on him. And I think it's one of the reasons why you'll see slightly more big plays, less sacks, and overall improvement vs Smith.

Stats help 'cut through the crap'.

In the latest presidential campaign, Obama's campaign ran on analytics and big data - everything was statistically-driven. Romney relied on the old'school approach: consultants. The consultants told him what to do, not the data. As a result, he was tactically "blown out" in Ohio, Florida, and Virginia.

The equivalent is listening to Brian Billick or some other talking head on NFLN or ESPN vs. looking at the data. Objectively, Kaepernick is twice as good.
Originally posted by Otohns:
Nickbradley, thanks for another good statistics based post. I know it takes some time and effort to crunch those numbers but I think these type of posts are good for shedding light on certain overlook facts and also serve for good chat fodder. I also know you never imply that statistics is the means-all for analyzing players but I agree that it can help put certain hard-to-quantify things into better perspective.

On a "non-statistical" note, I think the most impressive thing about Kaepernick so far is his ability to extend plays in the pocket. I know the media constantly talk about his legs and his arm. But in re-watching the games several times (for good fun, try watching his games with the imagination that it's Alex Smith behind center instead of him), the first thing that jumps out about Kaepernick is his ability to avoid pressure and extend plays. I think that alone makes him stand out vs Alex and I think is one of the main reasons why Harbaugh is so high on him. And I think it's one of the reasons why you'll see slightly more big plays, less sacks, and overall improvement vs Smith.

Agree 100%. Also another stat that doesn't appear is how big plays demoralize other teams and their fans (when playing away). A key 3rd and long conversion can swing the momentum in your direction.
Originally posted by SFTifoso:
Agree 100%. Also another stat that doesn't appear is how big plays demoralize other teams and their fans (when playing away). A key 3rd and long conversion can swing the momentum in your direction.

No. There is no such thing as momentum unless you believe in it. Statistically, its not there. Our eyes perceive a random sequence as a pattern when its not.

If a coin flip is 'heads' 5x in a row, 'heads' does not have momentum.

http://www.nfl.com/features/freakonomics/episode-3
Great post!
http://www.wired.com/playbook/2012/09/nfl-momentum/
Aaron Johnson, Alex Stimpson, and Torin Clark analyzed 473,621 plays run during the 2,931 NFL games played between 2000 and 2010 simply to determine whether big plays change the momentum of a game, motivating teams to perform better in subsequent drives. The results, presented in Turning the Tide: Big Plays and Psychological Momentum in the NFL (.pdf), found no evidence that a big defensive play has any effect on offensive performance later in the game.
  • buck
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Originally posted by nickbradley:
Originally posted by SFTifoso:
Agree 100%. Also another stat that doesn't appear is how big plays demoralize other teams and their fans (when playing away). A key 3rd and long conversion can swing the momentum in your direction.

No. There is no such thing as momentum unless you believe in it. Statistically, its not there. Our eyes perceive a random sequence as a pattern when its not.

If a coin flip is 'heads' 5x in a row, 'heads' does not have momentum.

http://www.nfl.com/features/freakonomics/episode-3

That is confusing, but I barely grasp statistics.

Momentum might not be there statistically, but as you said it can be there--when a person believes in it.

But, belief itself does not necessarily produce momentum.

If a person flipping a coin believes that heads has momentum, that belief would be erroneous and have no measurable impact on the statistical outcome of the coin toss.

That lack of measurable impact might be the coin flip or the cast of the dice, unlike football, is not impacted by human agency.
But, it could also a result the weakness of extant measuring devices.

edit: Thanks for the effort--I do think I understood some of point. Interesting.



[ Edited by buck on Nov 30, 2012 at 3:14 PM ]

  • GORO
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  • Posts: 2,250
Originally posted by nickbradley:
We've heard a lot of analysts talk about 'the explosive play', and why its so important to the NFL these days, and how Colin Kaepernick has far more of them than Alex Smith. Smith has 23 plays of 20+ yards (1 run) out of 267 passes, sacks, and runs. Kaepernick has 13 plays of 20 or more yards out of 111 passes, sacks, and runs. On plays of 25 yards or more, Smith has 11 and Kaepernick has 9. On plays of 30+ yards, Smith has 6 and Kaep has 7.

This is despite that fact that Smith has 2.5x more plays than Smith -- discussion closed, right? wrong.

Question: which quarterback is more dependent on the 'big play' for yards? The answer is that they're the same!

On plays that didn't result in a turnover (more later), Alex Smith averaged 6.64 yards per play (pass/run/sack). If you throw out the top 5% of his non-turnover plays, this drops to 5.2 yards per play (pass/run/sack). In other words, his biggest plays are responsible for 22% of his yards.

Let's turn to Kaepernick. On plays that didn't result in a turnover, Colin Kaepernick averaged 7.89 yards per play (pass/run/sack). If you throw out the top 5% of his non-turnover plays, this drops to 6.08 yards per play. In other words, his biggest plats are responsible for 23% of his yards.

Its basically the same (I had to Split a Kaepernick pass in half to fit it within the top 5%). If I threw out the top 25% of plays, the results don't change (much) - Smith got 62.5% of his non-turnover play yardage from the top 1/4th of his plays, while Kaep got 63.5%.

50.5% of Smith's plays resulted in 5 or more yards. Kaepernick, 49.5%. 63.7% of Smith's plays resulted in positive yardage. Kaep - 65.5%.

Tack on the fact that Smith was 25% more likely to commit a turnover than Kaepernick, and 60% more likely to be sacked than Kaepernick.

*** Simply put, Kaepernick has been better than Smith at everything, on all types of plays. Put any idea that he's just more likely to complete a big pass or run downfield out of your head completely.
The 49er Offense under Harbaugh picks it's shots when they go deep. So Alex has had big chunks of yardage, but he is really bad on third downs, he seems content to take a sack then to throw under durress.

Kaepernick will have more long yardage plays converted because he is willing and mentally he believes a Qb should be like Favre. So by season end we can compare their stats and see the difference.
Originally posted by buck:
That is confusing, but I barely grasp statistics.

Momentum might not be there statistically, but as you said it can be there--when a person believes in it.

But, belief itself does not necessarily produce momentum.

If a person flipping a coin believes that heads has momentum, that belief would be erroneous and have no measurable impact on the statistical outcome of the coin toss.

That lack of measurable impact might be the coin flip or the cast of the dice, unlike football, is not impacted by human agency.
But, it could also a result the weakness of extant measuring devices.

Well if the coin-flipper believed in momentum, he would stop flipping the coin out of frustration or sometihng.
  • buck
  • Veteran
  • Posts: 13,137
Originally posted by nickbradley:
Well if the coin-flipper believed in momentum, he would stop flipping the coin out of frustration or sometihng.


Or lose a lot of money at the crap table.
Originally posted by GORO:
The 49er Offense under Harbaugh picks it's shots when they go deep. So Alex has had big chunks of yardage, but he is really bad on third downs, he seems content to take a sack then to throw under durress.

Kaepernick will have more long yardage plays converted because he is willing and mentally he believes a Qb should be like Favre. So by season end we can compare their stats and see the difference.

Um, Alex Smith was godawful on third and 4th down. His EPA/play on 3rd and 4th down? NEGATIVE -0.05, a total of NEGATIVE 3.72. Kaepernick: 0.6 EPA/play, for a total of 16.39.

Strange data point: Alex Smith is better than Kaepernick on SECOND DOWN. Wierd?
Alex doesn't give you the big play as often as Kaepernick does. Kaep can extend plays that Alex cannot.
Alex checks down. Kaep throws down field. Alex sucks on 3rd down. Kaep is decent on 3rd down.
Alex can hit a donkey from 30 yards away. Kaep can kill a donkey from 50 yards away!
Hmmmmmmmm............ Nah let's stick with Alex
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