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Drinen's Notebook: Thursday, October 3, 2002
On matchups, strength of schedule, and always starting your studs...My intention was to fill this space with an exploration of the question: should you always start your studs?I designed a quick study to look at the issue. Here is the setup:
Now, I'll define two classes of RBs: studs and semi-studs. Studs are defined as RBs ranked in the top 10 for a given season. Semi-studs are RBs who ranked between 11 and 20. Likewise, I'll define two classes of defenses. "Good defenses" are defenses that ranked 1st through 10th for the season. "Bad defenses" are the ones that ranked 20th or worse. So the question is: is it better to play a semi-stud RB against a bad D, or a stud RB against a good D? The data shakes out as follows:
2000 ---- Average fantasy points for stud RBs against good Ds 14.7 Average fantasy points for semi-stud RBs against bad Ds 16.4 2001 ---- Average fantasy points for stud RBs against good Ds 12.6 Average fantasy points for semi-stud RBs against bad Ds 12.1 So, in 2000, the lesser back against a favorable D was a better play. In 2001, the studs did better, but only by a little. Overall, the data tilts slightly toward playing matchups instead of playing studs. But there is something wrong with this. To see what, consider the following example: In week 14 of 2000, Mike Anderson (a stud) faced a Saints defense that, at the time, was ranked #3. He hung 50 fantasy points on them. In large part because of Anderson's walking all over them, the Saints D finished the season down at #12. Therefore, they didn't get included in the study as a good defense even though, at the time, they clearly did look like a good D. In other words, the stud RB did so well against the tough matchup that, after the fact, it didn't look like a tough matchup anymore. There are plenty of other examples of this: Shaun Alexander against the Raiders in week 9 of last year, Curtis Martin against New England in week 7 of 2000, and a few instances involving Marshall Faulk. To get around this, we have to evaluate defenses based not on what we eventually ended up knowing about them, but based on what we would have known at the time the game was played. So I re-ran the study, but I looked at instances where a stud RB went against a defense that looked good (i.e. was ranked 1-10) at the time and instances where a semi-stud RB was going against a defense that looked bad at the time. The numbers below are average fantasy points per game:
2000 ---- Stud RBs against Ds that looked good at the time 17.1 Semi-stud RBs against Ds that looked bad at the time 15.9 2001 ---- Stud RBs against Ds that looked good at the time 14.4 Semi-stud RBs against Ds that looked bad at the time 12.4 [Technical note: because rankings in the early weeks are very flightly, only games from week 5 onward were counted here.] In this case, the studs come out looking quite a bit better both years. Ostensibly, the message here is: always start your studs. But I don't think this study supports that conclusion either. Why? Because, again, the above study separates the studs from the semi-studs after the fact. Just as we don't know who the good Ds are, we don't know who the stud RBs are either. So yes, of course you always start your studs. The tricky part is figuring out who your studs are. In other words, this column officially refuses to give a yes-or-no answer to the question of whether you should always start your studs. In fact, in the course of writing this column, I've basically come to the conclusion that it's a meaningless question. It seems to me that the only sensible way of defining "stud" is "a guy who you should start every week." This makes it easy to decide whether or not to start your studs. But it does nothing to help you figure out who your studs are. But that doesn't mean this column is a waste. The main point is: a team's defensive ranking can vary a whole lot over the course of a season. We've played four weeks so far this year, and here's how the rankings look right now:
Avg. FPT allowed
Team vs. RBs
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1. San Diego Chargers 10.6
2. Dallas Cowboys 11.0
3. Carolina Panthers 12.3
4. Jacksonville Jaguars 13.4
5. Tampa Bay Buccaneers 14.2
6. Philadelphia Eagles 14.2
7. New Orleans Saints 14.2
8. Tennessee Titans 14.9
9. Denver Broncos 14.9
10. Oakland Raiders 15.4
11. St. Louis Rams 15.4
12. Chicago Bears 17.2
13. Buffalo Bills 17.4
14. Pittsburgh Steelers 17.6
15. Houston Texans 17.8
16. Miami Dolphins 18.4
17. New York Giants 18.5
18. San Francisco 49ers 19.6
19. Baltimore Ravens 19.7
20. Arizona Cardinals 20.2
21. Washington Redskins 20.6
22. Cincinnati Bengals 21.7
23. Atlanta Falcons 22.0
24. Kansas City Chiefs 22.1
25. Indianapolis Colts 22.7
26. New England Patriots 22.9
27. Cleveland Browns 24.0
28. Minnesota Vikings 27.1
29. Detroit Lions 28.3
30. Green Bay Packers 31.3
31. Seattle Seahawks 33.1
32. New York Jets 37.7
So the Chargers, Cowboys, and Panthers look good and the Packers, Seahawks, and Jets don't. Now rewind. Here's how the rankings looked at the same point last year, along with each team's ranking for the rest of the season:
--- rank -----
Team Wk1-4 Wk5-17 change
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Baltimore Ravens 1 12 -11
Pittsburgh Steelers 2 1 1
Green Bay Packers 3 21 -18
San Diego Chargers 4 11 -7
New York Giants 5 7 -2
Denver Broncos 6 17 -11
Tampa Bay Buccaneers 7 15 -8
Oakland Raiders 8 25 -17
Chicago Bears 9 2 7
Atlanta Falcons 10 28 -18
Seattle Seahawks 11 16 -5
Cleveland Browns 12 29 -17
Minnesota Vikings 13 31 -18
San Francisco 49ers 14 14 0
New Orleans Saints 15 24 -9
St. Louis Rams 16 3 13
Dallas Cowboys 17 4 13
Jacksonville Jaguars 18 10 8
Carolina Panthers 19 30 -11
Kansas City Chiefs 20 26 -6
Cincinnati Bengals 21 6 15
Philadelphia Eagles 22 8 14
New England Patriots 23 5 18
Miami Dolphins 24 18 6
New York Jets 25 23 2
Buffalo Bills 26 22 4
Detroit Lions 27 20 7
Tennessee Titans 28 13 15
Arizona Cardinals 29 19 10
Washington Redskins 30 9 21
Indianapolis Colts 31 27 4
Look at the movers! This time last year, the Pack was #3. For the rest of the season, they were 21st. The Raiders moved from 8th to 25th, the Falcons from 10th to 28th, the Pats from 23rd to 5th, the Redskins from 30th to 9th. More than half the league's teams (16 out of 31) moved 10 or more places in the rankings. OK, you say, maybe week 4 is too early to make any kind of determination. Not so. Here's the same analysis, using week 9 instead:
--- rank -----
Team Wk1-9 Wk10-17 change
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Pittsburgh Steelers 1 1 0
Baltimore Ravens 2 18 -16
New York Giants 3 16 -13
Green Bay Packers 4 25 -21
Chicago Bears 5 3 2
St. Louis Rams 6 9 -3
San Diego Chargers 7 4 3
Seattle Seahawks 8 15 -7
Miami Dolphins 9 22 -13
Dallas Cowboys 10 12 -2
Denver Broncos 11 10 1
New England Patriots 12 8 4
Jacksonville Jaguars 13 14 -1
New Orleans Saints 14 30 -16
Philadelphia Eagles 15 11 4
Atlanta Falcons 16 27 -11
San Francisco 49ers 17 6 11
Oakland Raiders 18 21 -3
Tampa Bay Buccaneers 19 5 14
Tennessee Titans 20 13 7
Cincinnati Bengals 21 2 19
Cleveland Browns 22 28 -6
Arizona Cardinals 23 20 3
Indianapolis Colts 24 31 -7
New York Jets 25 23 2
Buffalo Bills 26 24 2
Detroit Lions 27 17 10
Kansas City Chiefs 28 19 9
Carolina Panthers 29 26 3
Minnesota Vikings 30 29 1
Washington Redskins 31 7 24
The 2000 data is a little more stable than the 2001, but it still contains a lot of teams whose defensive strength changed greatly from the first part of the season to the last:
--- rank -----
Team Wk1-9 Wk10-17 change
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Pittsburgh Steelers 1 25 -24
New Orleans Saints 2 27 -25
New York Giants 3 3 0
Buffalo Bills 4 24 -20
Baltimore Ravens 5 1 4
Washington Redskins 6 17 -11
Green Bay Packers 7 7 0
Tennessee Titans 8 2 6
New York Jets 9 14 -5
Miami Dolphins 10 16 -6
Tampa Bay Buccaneers 11 20 -9
Minnesota Vikings 12 26 -14
Philadelphia Eagles 13 12 1
Detroit Lions 14 22 -8
New England Patriots 15 11 4
Jacksonville Jaguars 16 6 10
Indianapolis Colts 17 23 -6
Oakland Raiders 18 9 9
San Diego Chargers 19 4 15
Cincinnati Bengals 20 19 1
Denver Broncos 21 8 13
Chicago Bears 22 5 17
Kansas City Chiefs 23 10 13
St. Louis Rams 24 21 3
Seattle Seahawks 25 30 -5
Cleveland Browns 26 31 -5
Carolina Panthers 27 13 14
San Francisco 49ers 28 15 13
Atlanta Falcons 29 18 11
Dallas Cowboys 30 28 2
Arizona Cardinals 31 29 2
One last look at the slippery nature of defensive rankings: here's a table showing how defenses of a given rank have performed over the last two years:
Avg. Fant.
Rank Pts. allowed
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1 13.3
2 17.8
3 16.4
4 17.4
5 18.4
6 18.0
7 18.5
8 17.8
9 18.6
10 17.6
11 21.2
12 19.6
13 16.2
14 18.9
15 16.8
16 17.3
17 12.8
18 18.1
19 18.6
20 23.7
21 18.2
22 20.2
23 21.4
24 20.7
25 22.5
26 20.0
27 17.3
28 20.4
29 22.9
30 22.8
31 22.5
Let's make sure that's clear. What this says is that teams that have come into a game ranked, for example, #3 have surrendered, on average, 16.4 fantasy points per game to RBs (technical note: only games from week 5 onward were counted). While higher-ranked teams have generally done better, there are some remarkable things here. For example, the defenses that have played best have been the 17th ranked defenses. Also, teams that were ranked #27 at the time have done better than teams ranked #2 at the time. These are flukes, but even if you smooth the data out a bit, you find that the difference between defenses that appear to be great and ones that appear to be terrible is not much. Defenses ranked in the top 5 (at the time) have surrendered an average of 16.7 fantasy points per game. Defenses ranked in the bottom 5 have given up 21.2. Yes, that's a real difference, and it might dictate who you start, but it's not nearly as big as it appears to be if you look at the current rankings (which show the top 5 defenses averaging around 12 and the bottom 5 averaging over 30).
Bottom LinePlaying matchups is very risky business. I'm not going to tell you to avoid playing matchups, but I will say this: if you weight strength-of-opponent heavily in your starting lineup decisions, you had better be using more than just current rankings to evaluate that strength. If you can spot a defense that will play poorly or play well in the future (because of injuries or the emergence of a new defensive stud or whatever), then by all means make use of that information. But be aware that the current defensive rankings will help you very little in predicting which defenses are going to perform well in the future.
Unless otherwise noted, all stats come from football-reference.com and the disclaimer applies
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