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Analyzing Cowboys’ 3rd Down Run Trends Thus Far in 2010



Jonathan Bales

A few months back, I published an article on the Cowboys’ 3rd down run plays from last season.  I did this to determine not only how successful the Cowboys were on these plays as compared to league averages, but also to learn if 3rd down runs held any strategic advantage over passes.

Here is a passage from that post:

In a recent post on why the Cowboys should pass out of “running” formations (and also in one on why teams should attempt a lot more 4th down plays), I spoke briefly about run/pass efficiency on 3rd down.  In short, NFL offenses fair much better when running the ball on 3rd and short (particularly 3rd and 1-3, but up until 3rd and 5).  Incredibly, running the ball is just as effective as passing up through 3rd and 10.  You can click the link above to read more about why this is so and view a graph displaying the conversion rates.

Nonetheless, I wanted to compare the Cowboys’ 2009 results with the league-wide numbers.  How effective was the offense when they ran the ball in “obvious” passing situations?  Note that these results (above) may be (very slightly) off from the numbers of Stats, Inc. or other unofficial stats companies because I did not use the televised ‘down and distance.’  For example, the televised version of a game may have mislabeled a play as ’3rd and 1′ when it was really closer to ’3rd and 2,’ and I have corrected for these mistakes to the best of my ability.

Notice the Cowboys’ yards-per-carry steadily rose (other than on 3rd and 6) as the yards-to-go increased.  This is obviously due to personnel and the game situation.  A defense which has substituted dime personnel on a 3rd and 10 is much more likely to yield a significant gain on the ground.  Of course, the yards-per-carry means nothing if the Cowboys are not achieving first downs.

2009 Third Down Conversion Rate

The chart to the right displays the conversion rate of all Cowboys’ 3rd down plays (of 10 or less yards-to-go) in 2009.  As you can see, the Cowboys were more efficient on 3rd and 1 or 2 when running the ball.  They converted 17/21 (81.0%) plays in these situations, compared to only 7/11 (63.6%) when passing.

As the distance-to-go increased, however, the conversion rate on runs dropped.  The Cowboys converted zero 3rd downs when running the ball with 8+ yards to go (although they attempted just four).

Interestingly, the conversion rate of 3rd down passes remained relatively stable, regardless of the distance-to-go.  You can see a very slight drop in the Cowboys’ 3rd down passing efficiency, but for the most part, the conversion rate was flat.  This is probably due more so to the team’s success in 3rd and long situations rather than an inability to convert on 3rd and short (when passing).

I give offensive coordinator Jason Garrett a lot of flack, but his 3rd down play-calling is generally outstanding.  I’d still love to see him run more on 3rd and medium (the ‘Boys ran just seven times on 3rd and 3-6 all season, compared to 42 passes).  Of course one would expect more passes in this range, but a slight increase in “surprise” runs would be in-tune with league-wide 3rd down conversion rates and could perhaps significantly aid the offense.

2010 3rd Down Runs

You can see above that the Cowboys’ 3rd down play-calling in 2009 fell in line with league averages: running was more successful than passing up until 3rd and 6.  I praised Garrett for his 3rd down play-calling last season, but I still hoped to see more 3rd downs runs this year.

So far, we are seeing those runs.  The chart to the left displays my findings.  Note that the sample size of plays is still small, so my mid-season and final analyses will be more statistically significant.  Still, it is interesting to see what sort of trends we can determine early in the season, if any.

Through three weeks, Garrett has run the ball a lot more on 3rd and 1-5.  In “true” short-yardage situations (one or two yards-to-go), the Cowboys have run on eight of nine plays this season.  That 88.9 percent rate is higher than last year’s 70.0 percent run rate in the same situations.  Further, the Cowboys are converting on a higher percentage of those runs.

On 3rd and 3-5, the Cowboys have run the ball twice this year.  That may not seem like much, but note that the Cowboys ran the ball just five times in that range in all of 2009.

Of course, we can’t be sure whether these numbers mean anything or not yet, but in combination with some of Garrett’s other early-season trends (which I will continue to detail throughout the bye week), it does appear as though the Cowboys’ much-scrutinized offensive coordinator is certainly using advanced statistics and game theory in a much more authoritative manner this season. . .and that is definitely a great thing.



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Dallas Cowboys 2009 Offensive Player Efficiency Comparisons

Last week, a reader suggested we perform a value-based statistical analysis (similar to our 2009 Player Grades) which could be used to determine the worth of one player over another.  For example, how much better would the Cowboys be if Felix Jones played every snap at running back (disregarding fatigue)?  How costly would an injury to Jason Witten be?  Essentially, how much does each player contribute to a win?

This task is easier said than done (and since it isn’t even particularly easily said, it sure isn’t easy to do).  As the reader points out, one would have to “normalize” the conditions outside of the player to determine his true worth.  This is rather easy to do (relatively speaking) in a sport like baseball where the circumstances are basically always the same.

In football, though, no two plays are ever really identical.  Statistical comparisons among players on different teams are rather pointless, as the nature of each player’s system plays an incredible role in his statistical capabilities.

Nonetheless, there have been some attempts to “normalize” outside factors and assign an objective value to players.  In fact, we are in the process of making such an attempt right now.  Until then, we wanted to take a look at the values of Cowboys players gathered by some other leading football statistics gurus (and compare them to our own 2009 Player Rankings).

One such source (and perhaps the most well-known) is Football Outsiders.  The primary FO statistic with which we are concerned is DVOA, or Defense-adjusted Value Over Average.  FO describes DVOA as “representing value, per play, over an average player at the same position in the same game situations.”

DVOA is an excellent statistic to use to compare with our own player rankings, as both represent efficiency, not overall value.  For example, Roy Williams had a greater overall value to the offense than Kevin Ogletree in 2009, but most would argue Ogletree was more efficient during his snaps.

Another source of efficiency-based value rankings is Advanced NFL Stats–a site we refer you to a lot.  Advanced NFL Stats implements a statistic called Expected Points Added.  We’ve spoken about ‘expected points’ in the past, and ANS talks about it here.

In short, EP (expected points) is the value of a certain situation in football.  EPA (expected points added) is the difference between one situation and another.  If the Cowboys have a 1st and 10 at their own 30-yard line, for example, the EP of that situation is +1.0 point, i.e. on average, they can expect one point from that drive.  If Miles Austin catches a pass for 50 yards, the Cowboys’ EP shoots up to +4.0 (the expected points of a 1st and 10 at the opponent’s 20-yard line).  Thus, the EPA for that play is +3.0.

We are concerned with EPA/play–the amount of expected points a player adds to his team’s point total per play.

A final source for efficiency-based values is Pro Football Focus.  PFF is different from FO and ANS in that they do not necessary use the outcomes of plays to formulate rankings.  Instead, they break down each play and assign values based on their interpretation of how well each player performed his job on that play.  You can read more about their methodology here.

It is important to note that all three sites use a value of “0” as a baseline for average play.  Players in the negative are worse than average, and players with positive values are better than average for DVOA, EPA, and PFF’s values.

Click to enlarge.

The chart above displays the rankings and values for the Cowboys offense from all three sites (Football Outsiders, Advanced NFL Stats, and Pro Football Focus), along with our own grades.  A few notes before we analyze the data:

  • NR=Not Rated (likely due to insufficient sample size)
  • The statistics circled in blue are a player’s highest rating; those in red are his lowest.
  • Comparisons among players at different positions are meaningless due to the nature of the data.

Observations

  • Only two players, Martellus Bennett and Flozell Adams, were unanimously voted as “below average.”

Shockingly, ANS rated Roy Williams as slightly above average.  We love Williams’ attitude right now, but we couldn’t disagree more about his 2009 play.

  • Tony Romo’s highest rating (from FO) put him at just 7th among all quarterbacks.  PFF had him all the way at 15th.

We had Romo rated as the 7th-best quarterback in the NFL in our 2010 Starting Quarterback Power Rankings.  We would have ranked his 2009 play, though, as top-five.

  • It’s unanimous: Felix Jones is one of the NFL’s most efficient running backs.  He was ranked 5th, 6th, and 9th, respectively.

Jones’ lowest grade would actually probably come from us.  He has a long way to go to prove he can hold up over an entire season, but as far as efficiency, he’s one of the league’s best.  We provided him a B+ in short-yardage running, an A in overall running, a B in receiving, and a B in pass protection.

  • Two out our three sources agree with us that Barber was about average last season.  FO ranked him as a top 15 back.  Meanwhile, Tashard Choice checked in with a higher efficiency rating than Jones from two of the sites.

We rated Barber as an average running back in 2009 (77.2 percent).  We were also very high on Choice, rating him just 2.5 percentage points behind Jones.  Choice would have ranked as one of the league’s top running backs on Football Outsiders and Advanced NFL Stats had he played more snaps.

  • Jason Witten was ranked all the way from the league’s top tight end to No. 11.

Witten was the No. 1 tight end in our NFL Tight End Rankings.  There’s simply no doubt about it.

  • Opinions on Deon Anderson varied from slightly below average to the league’s 6th-best fullback.

We tend to agree with the latter.  The Cowboys averaged nearly two yards more per rush with Anderson in the game (as compared to John Phillips) and .2 yards more per pass.  Click here to see our in-depth study on Anderson’s 2009 play.

  • Miles Austin has arrived.  He was rated from 5th to 9th.

We gave Austin the third-highest grade of any Cowboy due to his low 2.2 percent drop rate and incredible 10.4 yards-per-attempt.

  • Ratings of both Patrick Crayton and Roy Williams varied.

Two of the three sources had Crayton as a top 16 receiver (in terms of efficiency).  Williams wasn’t high on anyone’s list, but PFF had him ranked all the way down at No. 100.

  • PFF was the only site to rank individual linemen, but their ratings fell in line with ours.

We were a bit higher on Leonard Davis and Andre Gurode and slightly lower on Kyle Kosier (who they listed as the Cowboys’ top lineman last season).  We gave Davis and Gurode “A-” grades and Kosier a “B.”  All three linemen made our list of Dallas’ top 15 overall players last season.

Conclusion

There is obviously quite a bit of work left to be completed in the area of advanced football statistics, particularly objective efficiency rankings.  Still, the difficulty of the task is no reason to concede.  The more we learn which statistics contribute to a team’s success (and how much), the closer we will be to “normalizing” subjective factors in an attempt to acquire objective player ratings.

Up Next: 2009 Defensive Player Efficiency Comparisons

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Why Cowboys Should Throw Out of ‘Ace’ (And Other Double-Tight Formations)

By Jonathan Bales

A few weeks back, we published a breakdown of every formation the Cowboys ran in 2009, including run/pass ratios, success rates, and big/negative play percentages.  Included in that article was a double-tight (two tight ends) formation called “Ace”:

The Cowboys ran 29 plays out of “Ace” last season:

24 passes (82.8 percent)/5 runs (17.2 percent)

11.46 yards/attempt

2.00 yards/rush

12 passes 10+ (50 percent), five passes 20+ (20.8 percent), two negative runs (40 percent)

“Ace” was the Cowboys second-most efficient passing formation, and they also had a ton of success passing out of other double-tight formations.  Not exactly the statistics you were expecting from “run-oriented” formations?  Me neither. . .which is exactly why passing out of it was so successful last season.

I hate to harp on it again (actually, secretly I love it), but run/pass selection is controlled in large part by game theory.  In a nutshell, game theory is thinking one step ahead of your opponent.  Why perform a surprise onside kick?  Why run on 3rd and 7?  Because your opponent will never be expecting it.

This latter scenario (running the ball on 3rd and medium to long) is one I’ve already examined.  The graph to the left (from AdvancedNFLStats.com) displays the conversion rates of teams on 3rd down in various situations.  The excerpt below is one I wrote in my article on why teams should attempt a lot more 4th down plays, but it explains the graph.

In 3rd and 1 situations, offenses obtain a 1st down on 70% of runs, compared to just 58% of passes. In fact, running the ball on 3rd down actually yields the most success (in terms of achieving 1st downs) up until 3rd and 5. Surprisingly, passing the ball never becomes significantly advantageous over running the ball in any situation up through 3rd and 10.

The reason behind this has to do with game theory. If defenses were to remain in their base personnel regardless of the down and distance, running the ball in medium-to-long yardage situations would be generally unsuccessful. Since defenses substitute their nickel or dime personnel and dial up a play designed to defend a pass, however, offensive coordinators could increase their 3rd and 4th down conversion rates by calling far more runs in those situations.

Another way to look at it is that the play-calling of other offensive coordinators around the league affects that of Garrett. The two are not independent of one another. Running the ball on 3rd and short-to-medium is the optimum strategy not because of anything inherent in the game of football, but because of the play-calling of other offensive coordinators. If other OCs suddenly started calling a bunch of 3rd and 4th down runs, defenses would adjust, perhaps making passing the ball in those scenarios the optimum strategy.

The passing success of the Cowboys out of “Ace” and other “running” formations is equivalent to the success teams have when running the ball on 3rd down.  There is nothing inherently efficient about running the ball in these situations.  Rather, the success comes from your opponent’s expectations.

Similarly, passing out of “running” formations isn’t an inherently superior strategy to passing with four wide receivers on the field.  Instead, it works because of the defense.

Think of it like this. . .let’s say passing the ball out of a four-receiver set receives a hypothetical score of 80 points (this total is arbitrary and independent of a defense).  Passing the ball out of a double-tight formation, on the other hand, is intrinsically worth just 60 points.

So, why would a team choose the latter scenario–a “sub-optimal” strategy?  Because the strategy is only “sub-optimal” in theory.  In practice, the defense makes substitutions to be able to effectively defend each formation.  To counter the run against the double-tight formation, they knowingly decrease their ability to thwart the pass.

Thus, they may receive a pass defense score of 75 against a four-receiver set, but just 50 against double-tight.  In that case, passing the ball out of double-tight yields a 10 point advantage for the offense, compared to just a five point advantage when throwing the ball out of the “passing” formation.

Play selection is dominated by game theory, meaning the actions of other offensive coordinators around the league really should affect those of Cowboys OC Jason Garrett.  It is for this reason that I would love to see the Cowboys do the “unexpected”–pass more out of tight formations (and run more out of spread ones) in 2010.  The theoretical value may be sub-optimal, but the actual value would be maximized.

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Re-Analysis of 4th Down Attempts: The Impact of Momentum

Optimal 4th Down Decisions via mgoblog.com

A couple days ago, we published a study on the Cowboys’ 2009 4th down attempts, explaining why the offense, along with most others around the NFL, does no attempt nearly enough 4th down plays.  The Cowboys attempted just 11 plays on 4th down last season, converting on only four of them (36.4%).

Last night, I came across another study on 4th down attempts.  The conclusions of their original study were similar to those we discussed in our own article.

  1. Don’t punt on the opponent’s side of the field.
  2. Really consider going for it on 4th down after crossing your own 40.
  3. Field goals only make sense if there are more than 5 yards to go and you are between the 10 and 30 yard lines. If you’re in opponent territory and these two criteria aren’t true, you should be going for it.

However, they also raise (and rebut) a couple of objections to the “go for it” dictum.  They are listed below.

  • Failing on a 4th down attempt gives the opposing offense momentum they would have otherwise never received.

Offenses have no advantage if their drive is the result of a 4th down stop.

This was initially our biggest qualm with the notion of adhering to a (seemingly risky) 4th down chart.  The methodology seemed like it may work in principle but be less representative of reality when human emotions came into play.

However, the graph to the left shows that 4th down stops actually do not generate momentum for opposing offenses.  In fact, from 2007-2009, the total points obtained by drives following 4th down stops (2523) is less than the projected points for any drives starting at the same field position (2580).  Thus, “the big mo” appears to be more like “the big no,” at least as it relates to 4th down stops.

  • The model does not account for game-specific situations.

This is actually a valid objection.  MGoBlog.com points that out, writing:

The main flaw with the expected points model is that for most of the game all points are largely equal but at the end of the game, a field goal or even time can become crucially important.  If a field goal can tie a game, take the lead, or move said lead from one possession to two (or vice-versa), the decision-making process suggested above can shift radically.  This could mean punting near midfield to prevent a short field goal drive for the other team or taking a field goal instead going for it on fourth in field goal range.

However, the effect of situational 4th down calls is not as great as you may assume.  Until the 4th quarter, a coach’s decisions cannot be strongly correlated with the outcome of the game.

For example, when a team is down by four points with 30 seconds to go, the decision to go for it on 4th down is easy.  In the 3rd quarter, however, there are enough possessions left that there is less predictive power regarding the coach’s decision and the final score.  Thus, the 4th down chart is at least viable into the 4th quarter, and probably a bit beyond.

In any event, offenses around the league could benefit vastly from a more aggressive approach to 4th down play-calling.  Failures to convert appear to have little impact on game momentum, squashing our biggest fear of the real-life application of the model. Further, game-specific decisions are not nearly as common as people may believe.

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Alex Barron, Flozell Adams, and False Starts: How Costly Are They?

Peter King of Sports Illustrated recently noted that newly-acquired offensive tackle Alex Barron has racked up 43 false starts over the past five seasons–even more than ex-Cowboy Flozell Adams.  Fans cringed every time Adams moved prematurely, and his false starts became somewhat of a running joke in Big D.

When you play in St. Louis, however, your indiscretions (and unfortunately your successes, too) don’t get quite the attention as in Dallas.  Thus, fans likely were unaware (until now) of Barron’s similar penchant for jumping the gun.

But just how costly are false starts to a team’s win probability?  They certainly aren’t as costly as, say, holding penalties.  Still, they set back the offense not only in terms of yardage, but also momentum.

Perhaps a better way to measure the negative impact of false starts is to determine the impact they have on a team’s “Expected Points.”  Put simply, ‘expected points’ is the average points a team can expect to score on any particular drive based on their down and distance and field position.  Advanced NFL Stats, the creators of Expected Points, puts it like this:

Suppose the offense has a 1st and 10 at midfield.  This situation is worth +2.0 EP.  A 5-yard gain would set up a 2nd and 5 from the 45, which corresponds to a +2.1 EP.  Therefore, that 5-yard gain in that particular situation represents a +0.1 gain in EP.  This gain is called Expected Points Added (EPA).  Likewise, a 5-yard loss on 1st down at midfield would create a 2nd and 15 from the offense’s own 45.  That situation is worth +1.2 EP, representing a net difference of -0.8 EPA.

Thus, not all false starts are created equally.  A false start on 3rd and goal from the 3-yard line is much more debilitating to an offense than one on 3rd and 25 from midfield.

According to ANS, Barron’s false starts were responsible for the loss of 24.4 expected points over the course of five seasons, or about five points per year.  In essence, each false start cost the Rams 1/2 expected point, which is in line with league averages.

Expected points are one thing, but how do the false starts and subsequent loss of expected points affect a team’s win total?  Well, five points over the course of a season translates to just about .12 wins.  Thus, Barron’s (and those of Adams) false starts were annoying, but not as costly to a team’s success as you might believe.

That isn’t the end of the story, however.  Remember that Barron’s false starts cost his team about five points per season–but that total is only applicable as compared to a flawless offensive lineman.  In reality, even the best tackles commit false starts from time to time.  Let’s say our Pro-Bowl level replacement tackle commits just three false starts per season.  This translates to 1.5 expected points, and about .04 wins per season.

Ultimately, the difference between Barron and a lineman who commits just three false starts a season is only about .08 wins per year.  In comparison, we discovered that the difference between a good kicker (90% accuracy) and a poor kicker (70% accuracy) is approximately 1.05 wins per season.

Now, that does not mean kickers are 13 times as valuable as left tackles, but simply that false start penalties are nowhere near as costly as they may initially appear.

For the sake of Alex Barron’s sanity this season, let’s hope Cowboys fans around the country are made available to this information.

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Cowboys Film Study: 2nd and 1 Play-Calling

Advanced NFL Stats has published two interesting articles on the value of 2nd and 1 plays and the poor play-calling displayed throughout the NFL in these situations.  As you can see in the graph below, a nine yard gain on 1st down is extremely valuable to an offense.

Courtesy of Advanced NFL Stats

Why?  Well, think of it from the perspective of a defensive coordinator.  You want to stop the run to prevent a 1st down, but playing too aggressively against the run would create a vulnerability in your defense should the offense decide to pass.  Since 2nd and 1 is such a tremendous risk/reward situation for an offense, they could very well take a shot down the field.  If the result is an incomplete pass, they have a rather easy (relatively speaking) 3rd down play (meaning low risk), but the upside of a deep playaction pass, for example, is outstanding.

Game theory dictates that NFL offenses should be in the business of maximizing upside and minimizing risk, while defenses are looking to create low reward/high risk situations for offenses.

The value of a 2nd and 1 play is so incredible that, on average, a team will score .7 extra points each time they gain nine yards on 1st down as compared to gaining 10 yards.  Yes, gaining one less yard on 1st down provides a team with .7 more “expected points.”  In fact, 2nd and 1 plays are so valuable that they yield more expected points than any 1st down gain all the way up until 17 yards.  Thus, a nine-yard gain on 1st down is actually more valuable to an offense than a 16-yard gain.

The value of 2nd and 1 plays is even greater, though, if offensive coordinators take advantage of the situation.  This is not the case, however. League-wide, coaches called a run play on 78% of all 2nd and 1 plays.  That is even more than the 76% rate on 3rd and 1’s!

Further, only 4% of 2nd and 1 plays result in the offense going deep (throwing 15+ yards in the air).  This is fewer than all other 2nd down situations except 2nd and 4.

So why aren’t coaches taking advantage of the outstanding opportunity that comes with 2nd and 1 plays?  Disregarding the fact that most NFL coordinators are simply naturally conservative in their play-calling, we think the main reason is that they don’t want to deal with the stress of 3rd down.

Instead of utilizing the potential upside of 2nd and 1, they treat it as if it was simply another 3rd down.  Two opportunities to run the ball for just one yard?  Sounds good to me.  This thinking initially appears rational because it is the combination of plays which is most likely to result in a 1st down.  Offensive coordinators are supposed to do everything possible to obtain 1st downs, right?

Well, yes and no.  Of course a team needs to acquire 1st downs to move the ball, but coordinators should not be so focused on getting that next 1st down that they miss an opportunity for a huge play.  Take a look at this example:

Team A has 50 2nd and 1 situations throughout a season, running the ball on nearly every one.  They obtain 45 1st downs, but zero touchdowns on these plays.

Team B also has 50 plays on 2nd and 1, but they take a more balanced approach.  They throw about half the time, resulting in just 35 1st downs.  However, they score a touchdown on six of these plays.

So, which team would you rather coach?  For us, the low risk/high reward results obtained by Team B are much more appealing (and much more strongly-correlated with winning) than those of Team A.

Thus, offensive coordinators could increase the expected points of their offense dramatically by throwing out conventional wisdom and opening up the playbook a bit on 2nd and 1.

As you can see in the graph to the right, Cowboys’ offensive coordinator Jason Garrett’s play-calling on 2nd and 1 was nearly identical to the league average (he called a run on 80% of plays, compared to the 78% mean).  With Miles Austin and the newly-acquired Dez Bryant both athletic play-makers who thrive at getting deep, we would love to see the Cowboys employ a more balanced 2nd and 1 approach in 2010.

The chart also provides the run/pass ratio for all plays with a distance-to-go of three yards or less.  You can see that Garrett rarely exploited the high-reward opportunity of short-yardage 2nd down plays.  In fact, the Cowboys attempted just three passes of 15+ yards all season in 2nd or 3rd and 3 or less (3.22% of all plays in these situations).

We would actually like to see the red and blue lines in the graph to the right alternate places in 2010 (or at least move closer together).  A higher pass percentage on 2nd and short and a higher run percentage on 3rd and short, we believe, would result in not only more 1st down conversions for Dallas, but also (more importantly) a much larger opportunity to score quickly on big plays.

For an offense that tallied the second-most yards in the NFL in 2009 yet failed to crack the top 10 in points (14th), maximizing upside through the implementation of high-reward plays in short-yardage situations (particularly on 2nd down) may be just what the doctor ordered for the ‘Boys.