College Football Turnover Luck in 2015

Most aspects of football are mostly skill-based, but luck in large part governs turnovers. Or, aspects of turnovers at least. Today, I'm going over those random aspects. All stats are sourced from the excellent CFBStats.com.

Ball security is a skill. So is forcing fumbles. But recovering fumbles? It's basically all luck. The football has a funny shape and bounces in ways that people can't predict in real time. Besides that, it's not possible to control what mix of players from the two teams will be near the ball when it comes loose.

Here is the distribution of fumble recovery percentages from 2015 rounded to the nearest percentage:

It's in the shape of a bell curve, which means it's very likely to be random. And that point way at the top that was the most frequent fumble recovery percentage? It's 50%.

Here are all the teams from 2015 that recovered at least 60% of the fumbles in their games:

Name	Total Fumbles	Total Recovered	Recovered Pct.
Arkansas	29	19	65.5%
Houston	40	26	65.0%
Wisconsin	28	18	64.3%
Fresno State	30	19	63.3%
Oklahoma State	38	24	63.2%
Army	48	30	62.5%
USC	26	16	61.5%
Oregon	36	22	61.1%
South Carolina	38	23	60.5%
Kansas	40	24	60.0%
Navy	40	24	60.0%
North Carolina	45	27	60.0%
UNLV	30	18	60.0%

There is quite the mix here, from New Year's Six participants Houston and Oklahoma State down to Kansas and Army. Heading the other way, these are the teams that recovered fewer than 40% of their fumbles:

Name	Total Fumbles	Total Recovered	Recovered Pct.
Colorado	48	19	39.6%
Louisiana Tech	38	15	39.5%
Nebraska	26	10	38.5%
NC State	43	16	37.2%
Cincinnati	35	13	37.1%
Alabama	37	13	35.1%
Oregon State	26	9	34.6%
Duke	38	13	34.2%
Penn State	53	18	34.0%
Mississippi State	36	11	30.6%
Middle Tennessee	44	13	29.5%

Once again, the spread here is enormous from national champion Alabama to a pair of teams in Oregon State and Colorado that went a combined 1-17 in Pac-12 play.

The other category of turnovers is interceptions. Avoiding bad throws as a quarterback is a skill. Calling defensive sets to get defenders in the way of passes is a skill for coaches, as is knowing when to take risks to get picks for a player. Actually hauling in the interception does seem to be luck, though, which shouldn't be surprising considering that the players with the best hands tend to get put on offense.

Here is the distribution of interceptions as a percentage of passes defended (passes broken up plus INTs) rounded to the nearest percentage:

Again, it looks a lot like a random distribution. The percentage for all teams put together is 21.1%, and the median percentage was 20.7%.

Here are the teams that intercepted at least 30% of their passes defended:

Name	Int.	Passes Defended	INT Pct.
Connecticut	18	49	36.7%
Oklahoma State	17	49	34.7%
Appalachian State	18	52	34.6%
Arkansas State	26	77	33.8%
Bowling Green	20	60	33.3%
Oklahoma	20	61	32.8%
Boston College	13	41	31.7%
New Mexico State	12	38	31.6%
San Diego State	23	75	30.7%
Boise State	22	73	30.1%

There is a crazy mix here too, again from NY6 bowl teams like Oklahoma State and Oklahoma to BC, who didn't win an ACC game, and 3-9 New Mexico State. Boston College did have the No. 3 S&P+ defense, but NMSU's was fourth from the bottom and actually rated worse against the pass than the run. And now for the end of the list:

Name	Int.	Passes Defended	INT Pct.
Old Dominion	8	62	12.9%
North Texas	4	33	12.1%
Eastern Michigan	4	34	11.8%
UTEP	5	43	11.6%
TCU	7	63	11.1%
Iowa State	5	45	11.1%
Texas State	3	28	10.7%
Kansas State	5	47	10.6%
Vanderbilt	6	60	10.0%
UCF	4	40	10.0%
Louisiana-Lafayette	5	53	9.4%
Virginia	4	44	9.1%
Hawai'i	3	43	7.0%
Rice	2	32	6.3%

Down here is mostly bad teams, though we do get TCU sitting there at 11.1%. Vanderbilt may have missed a bowl, but it still had a top 20 defense.

Finally, coaches love to talk about turnovers like they're something within their control. To test that notion, I put every team's ranks in fumble recovery percentage and interception percentages in a table. I ran the correlation between the ranks, and it came out to 0.02. As a refresher: correlation is a number between 1 and -1, and the closer to zero it is, the less correlation there is between two factors. In other words, how good (or not) a team was at recovering fumbles tells us nothing about how good it was at intercepting passes it got a hand on and vice versa.

The implication here is that teams that were highly ranked in both were exceptionally lucky and those that were lowly ranked in both were exceptionally unlucky. Here are the lucky ones:

Team	Fumble Rank	INT Rank	Average Rank
Oklahoma State	5	2	4
South Carolina	9	13	11
Boston College	19	7	13
New Mexico	14	20	17
USC	7	28	18
Kansas	10	27	19
New Mexico State	34	8	21
Houston	2	43	23
South Florida	37	11	24
Miami (Florida)	17	33	25
Bowling Green	50	5	28
Arkansas State	55	4	30
Syracuse	44	15	30
Arizona State	30	29	30
Navy	11	49	30

And here are the snake bit teams:

Team	Fumble Rank	INT Rank	Average Rank
Eastern Michigan	80	117	99
Louisiana Tech	119	79	99
Alabama	123	77	100
Penn State	126	76	101
Mississippi State	127	78	103
Wyoming	94	111	103
Michigan	104	103	104
UTEP	89	118	104
Virginia	90	126	108
Rice	88	128	108
Cincinnati	122	97	110
Nebraska	120	99	110
Hawai'i	92	127	110
Texas State	107	121	114
Louisiana-Lafayette	116	125	121

Just imagine how good the Crimson Tide would've been with even just neutral luck in turnovers, much less good luck.

So those are the turnover luck extremes for 2015. Because this is an SEC-focused site, I'm going to put the tables for just the conference's teams below. If you're not an SEC fan or otherwise don't care, you're dismissed.

Fumble recovery percentages:

National Rank	Name	Total Fumbles	Total Recovered	Recovered Pct.
1	Arkansas	29	19	65.5%
9	South Carolina	38	23	60.5%
25	Missouri	36	20	55.6%
27	Tennessee	36	20	55.6%
40	LSU	36	19	52.8%
49	Georgia	46	24	52.2%
54	Vanderbilt	43	22	51.2%
61	Florida	44	22	50.0%
65	Kentucky	32	16	50.0%
72	Ole Miss	49	24	49.0%
74	Auburn	39	19	48.7%
117	Texas A&M	42	17	40.5%
123	Alabama	37	13	35.1%
127	Mississippi State	36	11	30.6%

Interception percentages:

National Rank	Name	Int.	Passes Defended	INT Pct.
13	South Carolina	12	42	28.6%
21	Georgia	12	45	26.7%
62	Auburn	14	67	20.9%
67	Florida	14	68	20.6%
69	Arkansas	11	54	20.4%
77	Alabama	19	99	19.2%
78	Mississippi State	13	68	19.1%
80	Texas A&M	11	58	19.0%
83	Kentucky	11	59	18.6%
84	Tennessee	12	65	18.5%
91	LSU	10	57	17.5%
94	Ole Miss	15	88	17.0%
96	Missouri	9	53	17.0%
123	Vanderbilt	6	60	10.0%

National ranks in both:

Team	Fumble Rank	INT Rank	Average Rank
South Carolina	9	13	11
Georgia	49	21	35
Arkansas	1	69	35
Tennessee	27	84	56
Missouri	25	96	61
Florida	61	67	64
LSU	40	91	66
Auburn	74	62	68
Kentucky	65	83	74
Mississippi	72	94	83
Vanderbilt	54	123	89
Texas A&M	117	80	99
Alabama	123	77	100
Mississippi State	127	78	103