Inspired by the general concensus that the number of returning starters in college football matter and a diary by NOLA Blue in which he discussed how Michigan would fare against opponents in 2011-12 based on returning starters, some of the comments (including my own) criticized looking at pure numbers of returning starters rather than the actual players returning.

It got me thinking if there was any predictablity to be found in pure numbers of returning starters (from now on referred to as RS) and if that translated into wins the next year by having a high amount of RS or losses by having a low amount.

Using Phil Steele's lists of RS I looked at the record for every team in a BCS conference plus Notre Dame in 2008-09, then listed how many starters they would be returning for the 2009-10 season, then added their record for the 2009-10 season, and noted the change in the amount of wins between the two seasons. I repeated that for the 2009-10 season going into the 2010-11 season.

One important note is that I had to decide what to do when teams played a different amount of games in consecutive seasons. For example a team plays 13 games in season one and goes 10-3. The next year in season two the same team plays 14 games and goes 10-4. Technically, they won the same amount of games in both years and the difference in wins is 0 but the team had an extra game to get 10 wins. I decided to handle this by using 0.5's  In this case I would give the team a win change of -0.5 for winning the same amount of games but having an extra game to do it in. This also works to the benefit of some teams.

Here is what I came up with:

Seasons 2008-09 to 2009-10

Team	2008-09 Record	2009 Returning Starters (* Denotes QB Return)	2009-10 Record	Net Win Change
Florida State	9-4	13*	7-6	-2
Boston College	9-5	14	8-5	-0.5
Maryland	8-5	10*	2-10	-5.5
Wake Forest	8-5	14*	5-7	-2.5
Clemson	7-6	15	9-5	+1.5
NC State	6-7	14*	5-7	-0.5
Virginia Tech	10-4	16*	10-3	+0.5
Georgia Tech	9-4	20*	11-3	+1.5
North Carolina	8-5	15*	8-5	0
Miami	7-6	17	9-4	+2
Virginia	5-7	13*	3-9	-2
Duke	4-8	13*	5-7	+1
Cincinnati	11-3	10*	12-1	+1.5
Pittsburgh	9-4	15*	10-3	+1
West Virginia	9-4	12	9-4	0
Rutgers	8-5	15	9-4	+1
Connecticut	8-5	14*	8-5	0
USF	8-5	14*	8-5	0
Louisville	5-7	15	4-8	-1
Syracuse	3-9	14*	4-8	+1
Penn State	11-2	10*	11-2	0
Ohio State	10-3	12*	11-2	+1
Michigan State	9-4	17	6-7	-3
Iowa	9-4	16*	11-2	+2
Northwestern	9-4	14	8-5	-1
Minnesota	7-6	16*	6-7	-1
Wisconsin	7-6	13*	10-3	+3
Illinois	5-7	15*	3-9	-2
Purdue	4-8	14	5-7	+1
Michigan	3-9	16	5-7	+2
Indiana	3-9	16	4-8	+1
Missouri	10-4	10	8-5	-1.5
Nebraska	9-4	14	10-4	+0.5
Kansas	8-5	16*	5-7	-2.5
Colorado	5-7	14*	3-9	-2
Kansas State	5-7	14	6-6	+1
Iowa State	2-10	17*	7-6	+4.5
Texas	12-1	17*	13-1	+0.5
Oklahoma	12-2	15*	8-5	-3.5
Texas Tech	11-2	13	9-4	-2
Oklahoma State	9-4	14*	9-4	0
Baylor	4-8	18*	4-8	0
Texas A&M	4-8	17*	6-7	+1.5
USC	12-1	12	9-4	-3
Oregon	10-3	9*	10-3	0
Oregon State	9-4	12*	8-5	-1
California	9-4	17*	8-5	-1
Arizona	8-5	14	8-5	0
Arizona State	5-7	15	4-8	-1
Stanford	5-7	18*	8-5	+2.5
UCLA	4-8	17*	7-6	+2.5
Washington State	2-11	15*	1-11	-0.5
Washington	0-12	18*	5-7	+5
Florida	13-1	20*	13-1	0
Georgia	10-3	16	8-5	-2
South Carolina	7-6	12	7-6	0
Vanderbilt	7-6	19	2-10	-4.5
Tennessee	5-7	13*	7-6	+1.5
Kentucky	7-6	11*	7-6	0
Alabama	12-2	14	14-0	+2
Mississippi	9-4	17*	9-4	0
LSU	8-5	14*	9-4	+1
Arkansas	5-7	19	8-5	+2.5
Auburn	5-7	17*	8-5	+2.5
Mississippi State	4-8	10*	5-7	+1
Notre Dame	7-6	17*	6-6	-0.5

And here is a table of number of RS and how many won more games, less games, or no change

Number of RS	No Change	+ Wins	- Wins	Total of Teams in Each Group
9	0	0	0	1
9*	1	0	0
10	0	0	1	5
10*	1	2	1
11	0	0	0	1
11*	1	0	0
12	2	0	1	5
12*	0	1	1
13	0	0	1	6
13*	0	3	2
14	1	4	2	15
14*	3	2	3
15	0	2	2	9
15*	1	1	3
16	0	2	1	7
16*	0	2	2
17	0	1	1	10
17*	1	5	2
18	0	0	0	3
18*	1	2	0
19	0	1	1	2
19*	0	0	0
20	0	0	0	2
20*	1	1	0

Here is some info to take away from this.

When I refer to same, more, or less I am talking about the amount of wins between the two seasons.

Overall Win Amount: 13 same (19.69%), 29 more (43.93%), 24 less (36.36%) Total: 66 teams

RS with a QB win difference: 10 same (23.26%), 19 more (44.19%), 14 less (32.56%) Total: 43 teams

RS without a QB win difference: 3 same (13.04%), 10 more (43.48%), 10 less (43.48%) Total: 23 teams

9-13 RS: 5 same (27.78%), 6 more (33.33%), 7 less (38.89%) Total: 18 teams
14-16 RS: 5 same (16.13%), 13 more (41.94%), 13 less (41.94%) Total: 31 teams
17-20 RS: 3 same (17.65%), 10 more (58.82%), 4 less (23.53%) Total: 17 teams

I figured teams would be more successful with a returning QB and while that is supported somewhat in these years with 44.19% of teams going on to a better record the next season the teams without a returning QB were equally as likely to be more or less successful proving the lack of an experienced QB didn't significantly lessen the chances of improvement.

As the number of RS increased more teams did improve but I was surprised to see that not until a team returned 17 starters was it significantly more likely to. In the 15 or 16 RS number it still seemed close to a 50/50 to expect more or less wins.

More after the break

Seasons 2009-10 to 2010-11 

Team Name	2009-10 Record	2010 Returning Starters (* Denotes QB Return)	2010-11 Record	Net Win Change
Florida State	7-6	14*	10-4	+2.5
Boston College	8-5	15*	7-6	-1
Maryland	2-10	13	9-4	+6.5
Wake Forest	5-7	15	3-9	-2
Clemson	9-5	14*	6-7	-2.5
NC State	5-7	13*	9-4	+3.5
Virginia Tech	10-3	13*	11-3	+0.5
Georgia Tech	11-3	18*	6-7	-4.5
North Carolina	8-5	19*	8-5	0
Miami	9-4	16*	7-6	-2
Virginia	3-9	16	4-8	-1
Duke	5-7	16	3-9	-2
Cincinnati	12-1	13	4-8	-7.5
Pittsburgh	10-3	12	8-5	-2
West Virginia	9-4	17	9-4	0
Rutgers	9-4	14*	4-8	-4.5
Connecticut	8-5	16*	8-5	0
USF	8-5	14*	8-5	0
Louisville	4-8	14*	7-6	+2.5
Syracuse	4-8	20	8-5	+3.5
Penn State	11-2	13	7-6	-4
Ohio State	11-2	15*	12-1	+1
Michigan State	6-7	15*	11-2	+5
Iowa	11-2	14*	8-5	-3
Northwestern	8-5	16	7-6	-1
Minnesota	6-7	12*	3-9	-2.5
Wisconsin	10-3	18*	11-2	+1
Illinois	3-9	14	7-6	+3.5
Purdue	5-7	12	4-8	-1
Michigan	5-7	15*	7-6	+1.5
Indiana	4-8	14*	5-7	+1
Missouri	8-5	19*	10-3	+2
Nebraska	10-4	18*	10-4	0
Kansas	5-7	16	3-9	-2
Colorado	3-9	16*	5-7	+2
Kansas State	6-6	15	7-6	+0.5
Iowa State	7-6	13*	5-7	-1.5
Texas	13-1	14	5-7	-7
Oklahoma	8-5	15*	12-2	+3.5
Texas Tech	9-4	15*	8-5	-1
Oklahoma State	9-4	10	11-2	+2
Baylor	4-8	14*	7-6	+2.5
Texas A&M	6-7	19*	9-4	+3
USC	9-4	12*	8-5	-1
Oregon	10-3	18*	12-1	+2
Oregon State	8-5	17	5-7	-2.5
California	8-5	16*	5-7	-2.5
Arizona	8-5	13*	7-6	-1
Arizona State	4-8	10	6-6	+2
Stanford	8-5	16*	12-1	+4
UCLA	7-6	15*	4-8	-2.5
Washington State	1-11	18*	2-10	+1
Washington	5-7	20*	7-6	+1.5
Florida	13-1	15	8-5	-4.5
Georgia	8-5	18	6-7	-2
South Carolina	7-6	17*	9-5	+1.5
Vanderbilt	2-10	11*	2-10	0
Tennessee	7-6	13	6-7	-1
Kentucky	7-6	13*	6-7	-1
Alabama	14-0	10*	10-3	-3.5
Mississippi	9-4	11	4-8	-4.5
LSU	9-4	12*	11-2	+2
Arkansas	8-5	18*	10-3	+2
Auburn	8-5	16	14-0	+5.5
Mississippi State	5-7	17	9-4	+3.5
Notre Dame	6-6	17	8-5	+1.5

 

Number of RS	No Change	+Wins	-Wins	Total Teams  in Each Group
10	0	2	0	3
10*	0	0	1
11	0	0	1	2
11*	1	0	0
12	0	0	2	5
12*	0	1	2
13	0	1	3	9
13*	0	2	3
14	0	1	1	10
14*	1	4	3
15	0	1	2	10
15*	0	4	3
16	0	1	4	10
16*	1	2	2
17	1	2	1	5
17*	0	1	0
18	0	0	1	7
18*	1	4	1
19	0	0	0	3
19*	1	2	0
20	0	1	0	2
20*	0	1	0

Overall Win Amount: 6 same (9.09%), 30 more (45.45%), 30 less (45.45%) Total: 66 teams

RS with a QB win difference: 5 same (12.20%), 21 more (51.22%), 15 less (36.59%) Total: 41 teams

RS without a QB win difference: 1 same (4%), 9 more (36%), 15 less (60%) Total: 25 teams

10-13 RS: 1 same (5.26%), 6 more (31.58%), 12 less (63.16%) Total: 19 teams
14-16 RS: 2 same (6.67%), 13 more (43.33%), 15 less (50%) Total: 30 teams
17-20 RS: 3 same (17.65%), 11 more (64.71%), 3 less (17.65%) Total: 17 teams

RS QBs seemed to be more important in these years 51.22% improved on wins with a returning QB and even more 60% got worse when they did not have one. Still the effect of a QB is not quite as overwhelming as might be expected.

Again with the magic number of 17 RS being the big difference where you could predict it was likely teams with 17 RS or more would improve. More teams actually got worse when they returned 16 starters and with 15 RS it was 50/50

Combined numbers for the two:

Overall: 19 same (14.39%), 59 more (44.70%), 54 less (40.91%) Total: 132 teams

RS with a QB win difference: 15 same (17.86%), 40 more (47.62%), 29 less (34.52%) Total: 84 teams

RS without a QB win difference: 4 same (8.33%), 19 more (39.58%), 25 less (52.08%) Total: 48 teams

9-13 RS: 6 same (16.22%), 12 more (32.43%), 19 less (51.35%) Total: 37 teams
14-16 RS: 7 same (11.48%), 26 more (42.62%), 28 less (45.90%) Total: 61 teams
17-20 RS: 6 same (17.65%), 21 more (61.76%), 7 less (20.59%) Total: 34 teams

Tidbits:

For teams with 17+ RS and QB in both years combined 5 same (20.83%), 16 better (66.67%), 3 worse (12.50%) Total: 24 teams

Cincinnati was the only team that played less games a season later yet had more wins so even though only 1 win better gave them +1.5
Texas is only team to play 2 less games a season later so even though they won 8 less games they get only -7 (Two 0.5's)

Analysis:

While these numbers are fun to look at and see RS alone only seems to matter for the really large number of RS or really small number, these numbers do very little to accomplish predicting the future. With only two sets of data that I have looked at so far it is hard to say anything is a trend. I may add the 2007-08 to 2008-09 season and the 2010-11 to 2011-12 eventually too to hopefully increase accuracy.

There are other problems like including a team that goes from 14-0 to 13-1 as getting worse in these numbers but hopefully that is counteracted by teams going 2-10 and getting better.

So many more things can be done with this kind of data if someone's so inclined like including the non BCS teams or comparing the BCS teams against the non BCS. Maybe do something more clever like score how many wins a team improves by into some type of ranking system

Maybe RS do not predict anything but still as a Michigan fan looking at these numbers of 2011 RS and seeing we return 20 starters with that one QB we all love I am hoping they go a long way.