Career Ratings For the Sam Bradford/Jay Schroeder Index Posts

by Chase Stuart on May 23, 2017

Two pretty accurate passers.

Last week, I published two posts on quarterbacks based on their completion percentage and yards per completion averages, relative to league average. The Sam Bradford Index post looks at quarterbacks with high completion percentages and low yards/completion averages, while the Jay Schroeder Index looks at the reverse. Freddy Alejandro made a request for career ratings in the comments, and with the help of Bryan Frye’s formula, I went ahead and generated those ratings.

Note that when calculating single-season standard deviations in both completion percentage and yards per completion, I used two modifications from last week’s posts. One, I used a three-year rolling average, and two, I used all passers (and not just qualifying passers) to calculate standard deviations. These combinations had the effect of making the standard deviations greater, which makes the Z-Scores smaller. As a result, the numbers are more compressed than they were last week, in addition to the fact that career ratings always bring less extreme ratings than a list of single-season leaders.

The most extreme rating belongs to Joe Montana, who for his career was 1.23 standard deviations above average in completion percentage. That’s the second-best rating, behind only Steve Young: each passer led the NFL in completion percentage five different times. From 1980 to 1997, 49ers passers led the league in completion percentage 10 times, with the rest of the league winning just eight crowns.

The difference between Young and Montana: Young had a slightly above-average yards per completion average for his career, while Montana was slightly below-average. ^[1]Despite Montana finishing with a higher Yd/Cmp average for his career, that is a function of era; Montana never finished higher than 10th in that metric, while Young had three top-5 finishes and … Continue reading And remember, this metric is calculated by taking each passer’s Z-Score in completion percentage and then subtracting their Z-Score in yards/completion, so a negative number in the latter category leads to a higher rating. After all, we are trying to identify the passers who had the highest completion percentages with the lowest yards per completion averages.

Note that this is a measure of style, not quality. Finishing high or low on this list is neither inherently good or bad. Joining Montana in the top 3 is Chad Pennington, although most of the top quarterbacks are Hall of Famers. Take a look:

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Rk	Quarterback	First Yr	Last Yr	Att	Z-Score Cmp%	Z-Score Yd/Cmp	Total
1	Joe Montana	1979	1994	5391	1.23	-0.28	1.51
2	Sammy Baugh	1937	1952	2995	1.14	-0.24	1.38
3	Chad Pennington	2000	2010	2471	1.09	-0.28	1.37
4	Drew Brees	2001	2016	8758	1.10	-0.10	1.20
5	Sonny Jurgensen	1957	1974	4262	1.00	-0.19	1.19
6	Bart Starr	1956	1971	3149	1.07	-0.12	1.18
7	Steve Young	1985	1999	4149	1.35	0.23	1.12
8	Ken Stabler	1970	1984	3793	0.92	-0.17	1.09
9	Troy Aikman	1989	2000	4715	0.78	-0.30	1.07
10	Frankie Albert	1946	1952	1564	0.70	-0.36	1.06
11	Fran Tarkenton	1961	1978	6467	0.86	-0.20	1.06
12	Len Dawson	1957	1975	3741	0.95	-0.08	1.03
13	John Brodie	1957	1973	4491	0.68	-0.32	1.01
14	Ken Anderson	1971	1986	4475	0.86	-0.12	0.99
15	Y.A. Tittle	1948	1964	4395	0.82	-0.16	0.98
16	Brad Johnson	1994	2008	4326	0.59	-0.39	0.98
17	Bernie Kosar	1985	1996	3365	0.58	-0.39	0.97
18	Brian Griese	1998	2008	2796	0.66	-0.24	0.90
19	Peyton Manning	1998	2015	9380	0.99	0.11	0.89
20	Frank Tripucka	1949	1963	1745	0.17	-0.72	0.89

Showing 1 to 20 of 185 entries

On the other side of the spectrum is, unsurprisingly, Jay Schroeder followed by Derek Anderson and Cam Newton. Schroeder, Newton, and Steve Grogan are the top three players in standard deviations above average in yards per completion, while Anderson, Mike Pagel and Rex Grossman are the bottom three in completion percentage.

Meanwhile, Kyle Boller, Sam Bradford and Frank Tripucka are the bottom three in yards per completion.

What stands out to you?

References[+]

References
↑1	Despite Montana finishing with a higher Yd/Cmp average for his career, that is a function of era; Montana never finished higher than 10th in that metric, while Young had three top-5 finishes and three more top-10 finishes.

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