When Does Yards After Catch Stabilize for Wide Receivers?

I’ve been watching the NFL for 30+ years, and there doesn’t seem to be a game that goes by without the commentary team citing a WR’s yards after catch (YAC) at some point during the broadcast. But should they? Today’s post seeks to answer that question.

Methods

They’re the same as always. To save some space, I’ll just remind everyone that this is a split-half reliability test, the applied-to-football methodological details of which you can read about here — and extrapolate to WR YAC — if you’re so inclined.

Results and Discussion

Below is the familiar stability table, this time for WR YAC:

Games	n	r	R2 = 0.50	Avg YAC	Obs 5.00 YAC
4	625	0.09	38	4.26	4.63
8	429	0.20	31	4.32	4.66
12	308	0.32	26	4.36	4.68
16	220	0.36	28	4.44	4.72
20	164	0.44	25	4.47	4.74
24	114	0.47	27	4.65	4.82
28	79	0.52	26	4.61	4.81
32	57	0.62	20	4.60	4.80
36	49	0.64	21	4.60	4.80
Wtd Average			31	4.38	4.69

I haven’t done so in a while, so here’s how to read the table if you’re a newcomer to these posts. Each row represents a player-game group. The third row, for example, has “12” in the “Games” column because it includes all WRs that played at least 24 games with the same team since 2006, and I’ve both a) randomly selected 24 games if they played more than 24, and b) randomly split the 24 games into two sets of 12. From there,

• the “n” column represents the number of WRs in each group,
• the “r” column shows the correlation between each group’s two sets of games,
• the “R² = 0.50″ column mathematically converts the group’s correlation into the number of games it takes for WR YAC to reflect 50% skill and 50% luck (aka the stabilization point),
• the “Avg YAC” column shows the group’s average YAC,
• and the “Obs 5.00 YAC” column regresses a 5.00 Actual YAC toward’s the group’s average YAC based on how long it takes for that group’s YAC to stabilize.

The bottom row labeled “Wtd Average” reveals the table’s take-home finding. In this case, it shows us that WR YAC takes 31 games to stabilize. And given an average of 3.2 receptions, 5.3 targets, and 26.1 routes run per game in my sample, this translates to about 100 receptions, 163 targets, and 801 routes. In what may come as a surprise, this is nearly twice as long as it takes TE YAC to stabilize (22 games, 58 receptions, 84 targets, and 408 routes).

What’s more, if we compare these findings to those for WR stats I’ve analyzed previously, we can conclude that YAC is considerably less reliable than average depth of target (aDOT, aka air yards), targets per route run (TPRR), receptions per route run (RPRR), and yards per route run (YPRR), while only being slightly more reliable than touchdowns per route run (TDPRR) and, duh, yards per target (YPT).

Two other conclusions we can draw from today’s result respect the questions I posed at the beginning of this YAC series. First, focusing on the above comparison with WR aDOT, it turns out that YAC takes nearly eight times longer to stabilize (i.e., 31 games vs. 8 games). Therefore, the choice of which one to use for WR prediction is a no-brainer. Second, given that WR YAC takes longer to stabilize than TE YAC, whereas TE aDOT takes longer than WR aDOT, we can now answer my second question: The rank order of reliability between positions for YAC is not the same as the rank order of reliability for aDOT.

Finally, converting Actual YAC into True YAC, below are the standings for all WRs that played at least 25 percent of snaps in 2016 per Pro Football Focus:

Player	Tm	G	Rec	Actual YAC	Rk	True YAC	Rk
Golden Tate	DET	16	91	6.8	4	5.5	1
Jarvis Landry	MIA	16	94	6.7	5	5.5	2
Adam Humphries	TB	15	55	7.1	2	5.3	3
Taylor Gabriel	ATL	12	35	8.1	1	5.3	4
Tyrell Williams	SD	16	69	6.5	6	5.2	5
Quincy Enunwa	NYJ	16	58	6.2	8	5.0	6
Cordarrelle Patterson	MIN	16	52	6.3	7	5.0	7
Randall Cobb	GB	12	60	6.1	9	5.0	8
Mike Wallace	BLT	16	72	5.8	14	4.9	9
Jamison Crowder	WAS	16	67	5.7	15	4.8	10
Odell Beckham Jr.	NYG	16	101	5.3	25	4.8	11
Marqise Lee	JAX	16	63	5.6	16	4.8	12
Amari Cooper	OAK	16	83	5.4	18	4.8	13
Chris Hogan	NE	15	38	6.1	9	4.8	14
Davante Adams	GB	16	75	5.4	18	4.8	15
Willie Snead	NO	15	72	5.4	18	4.7	16
Michael A. Thomas	NO	15	92	5.2	29	4.7	17
Brandon LaFell	CIN	16	64	5.4	18	4.7	18
Allen Hurns	JAX	11	35	5.9	12	4.7	19
Eddie Royal	CHI	9	33	5.9	12	4.7	20
Doug Baldwin	SEA	16	94	5.1	31	4.7	21
Cody Core	CIN	6	17	6.9	3	4.7	22
Julian Edelman	NE	16	98	5.0	36	4.6	23
Cole Beasley	DAL	16	75	5.1	31	4.6	24
Julio Jones	ATL	14	83	5.0	36	4.6	25
Travis Benjamin	SD	14	47	5.3	25	4.6	26
Tyler Lockett	SEA	14	41	5.4	18	4.6	27
Seth Roberts	OAK	16	38	5.4	18	4.6	28
Mohamed Sanu	ATL	15	59	5.1	31	4.6	29
Quinton Patton	SF	13	37	5.4	18	4.6	30
Breshad Perriman	BLT	15	33	5.3	25	4.5	31
Albert Wilson	KC	14	31	5.3	25	4.5	32
DeSean Jackson	WAS	15	56	4.9	40	4.5	33
Sammie Coates	PIT	11	21	5.5	17	4.5	34
J.J. Nelson	ARZ	14	34	5.1	31	4.5	35
Victor Cruz	NYG	14	39	5.0	36	4.5	36
Malcolm Mitchell	NE	11	32	5.1	31	4.5	37
Brandin Cooks	NO	15	78	4.7	42	4.5	38
Bennie Fowler	DEN	10	11	6.1	9	4.5	39
Tyreek Hill	KC	16	61	4.7	42	4.4	40
Tavon Austin	LA	15	58	4.7	42	4.4	41
Ricardo Louis	CLV	7	18	5.2	29	4.4	42
Will Fuller	HST	14	47	4.7	42	4.4	43
Pierre Garcon	WAS	16	79	4.5	48	4.4	44
Cameron Meredith	CHI	14	66	4.5	48	4.4	45
Jordan Taylor	DEN	11	16	4.9	40	4.4	46
Phillip Dorsett	IND	15	33	4.6	47	4.4	47
Devin Funchess	CAR	14	23	4.7	42	4.4	48
Jaron Brown	ARZ	6	11	5.0	36	4.3	49
Kenny Stills	MIA	16	42	4.5	48	4.3	50
Adam Thielen	MIN	16	69	4.4	52	4.3	51
Kenny Britt	LA	15	68	4.4	52	4.3	52
DeVante Parker	MIA	15	56	4.4	52	4.3	53
Paul Richardson	SEA	11	21	4.5	48	4.3	54
Rod Streater	SF	13	18	4.4	52	4.3	55
Marvin Jones	DET	15	55	4.3	56	4.3	56
Eli Rogers	PIT	13	48	4.3	56	4.3	57
Corey Brown	CAR	15	27	4.3	56	4.3	58
Andre Roberts	DET	13	14	4.3	56	4.3	59
Kendall Wright	TEN	11	29	4.2	60	4.3	60
Andrew Hawkins	CLV	16	33	4.2	60	4.3	61
Brian Quick	LA	16	41	4.2	60	4.3	62
Aldrick Robinson	ATL	13	20	4.1	63	4.2	63
Dorial Green-Beckham	PHI	14	36	4.1	63	4.2	64
Bryan Walters	JAX	8	24	4.0	67	4.2	65
A.J. Green	CIN	10	66	4.1	63	4.2	66
Steve L. Smith	BLT	14	70	4.1	63	4.2	67
Charone Peake	NYJ	11	19	3.8	72	4.2	68
Jordan Norwood	DEN	14	21	3.7	74	4.2	69
Braxton Miller	HST	9	15	3.5	84	4.2	70
Cody Latimer	DEN	7	8	2.9	103	4.2	71
Sterling Shepard	NYG	16	65	4.0	67	4.2	72
Charles D. Johnson	MIN	13	20	3.6	80	4.2	73
Ryan Grant	WAS	11	9	2.9	103	4.2	74
Jeff Janis	GB	10	11	3.1	96	4.2	75
Tyler Boyd	CIN	16	54	3.9	70	4.1	76
Jordy Nelson	GB	16	97	4.0	67	4.1	77
James Wright	CIN	10	13	2.9	103	4.1	78
Russell Shepard	TB	12	23	3.4	85	4.1	79
Walt Powell	BUF	7	14	2.9	103	4.1	80
Dontrelle Inman	SD	16	58	3.8	72	4.1	81
Terrance Williams	DAL	15	44	3.7	74	4.1	82
Brittan Golden	ARZ	7	8	1.9	123	4.1	83
Antonio Brown	PIT	15	106	3.9	70	4.1	84
Torrey Smith	SF	12	20	3.1	96	4.1	85
Kamar Aiken	BLT	16	29	3.4	85	4.1	86
Alshon Jeffery	CHI	12	52	3.7	74	4.1	87
Chris Conley	KC	16	44	3.6	80	4.1	88
Kelvin Benjamin	CAR	16	63	3.7	74	4.1	89
Ted Ginn	CAR	16	54	3.6	80	4.0	90
Danny Amendola	NE	11	23	3.0	99	4.0	91
Jermaine Kearse	SEA	16	41	3.4	85	4.0	92
Roger Lewis	NYG	9	7	0.3	130	4.0	93
Stefon Diggs	MIN	13	84	3.7	74	4.0	94
Andre Holmes	OAK	14	14	2.1	119	4.0	95
Josh Bellamy	CHI	12	19	2.6	113	4.0	96
Demaryius Thomas	DEN	16	90	3.7	74	4.0	97
Chester Rogers	IND	9	19	2.5	115	4.0	98
Jaelen Strong	HST	6	14	1.9	123	4.0	99
Corey Coleman	CLV	10	33	3.0	99	4.0	100
T.Y. Hilton	IND	16	91	3.6	80	4.0	101
Justin Hardy	ATL	11	21	2.4	118	4.0	102
Nelson Agholor	PHI	15	36	3.0	99	3.9	103
Jeremy Kerley	SF	16	64	3.4	85	3.9	104
Rishard Matthews	TEN	16	65	3.4	85	3.9	105
Brandon Coleman	NO	13	26	2.6	113	3.9	106
Anquan Boldin	DET	16	67	3.4	85	3.9	107
Marquise Goodwin	BUF	14	29	2.7	111	3.9	108
Jeremy Maclin	KC	12	44	3.0	99	3.9	109
Brandon Marshall	NYJ	15	59	3.2	93	3.9	110
Vincent Jackson	TB	5	15	1.2	128	3.9	111
Donte Moncrief	IND	9	30	2.5	115	3.9	112
Deonte Thompson	CHI	9	22	2.0	121	3.9	113
John Brown	ARZ	14	39	2.8	108	3.9	114
Cobi Hamilton	PIT	11	17	1.4	127	3.9	115
Brice Butler	DAL	14	16	1.2	128	3.9	116
Emmanuel Sanders	DEN	15	79	3.3	92	3.8	117
Robby Anderson	NYJ	14	42	2.8	108	3.8	118
Larry Fitzgerald	ARZ	16	107	3.4	85	3.8	119
Jordan Matthews	PHI	14	73	3.2	93	3.8	120
Dez Bryant	DAL	12	50	2.9	103	3.8	121
DeAndre Hopkins	HST	16	78	3.2	93	3.8	122
Michael Crabtree	OAK	16	89	3.1	96	3.7	123
Sammy Watkins	BUF	8	28	1.7	125	3.7	124
Robert Woods	BUF	13	51	2.5	115	3.7	125
Tajae Sharpe	TEN	16	41	2.1	119	3.6	126
Michael Floyd	ARZ	12	33	1.7	125	3.6	127
Terrelle Pryor	CLV	16	77	2.8	108	3.6	128
Allen Robinson	JAX	16	73	2.7	111	3.6	129
Mike Evans	TB	16	96	2.0	121	3.2	130
				4.3

As seems to be the theme of this post, I think the most valuable information here comes from juxtaposing it with the True WR aDOT standings I posted previously. If we focus on the Top 10 above, we find (unsurprisingly) the usual suspects in a lineup based on “Who runs a bunch of short, zone-attacking routes?” To wit, Golden Tate ranks 1st in True YAC, but ranked 116th in True aDOT, Jarvis Landry ranked 127th in True aDOT, Adam Humphries ranked 129th, Quincy Enunwa ranked 102nd, Cordarelle Patterson ranked 130th, Randall Cobb ranked 125th, and Jamison Crowder ranked 117th. The predictive value, then, comes — as it usually does — from the outliers: Taylor Gabriel ranked a respectable 69th in True aDOT, Tyrell Williams ranked 48th, and Mike Wallace ranked 49th. It seems to me that these three are WRs who were targeted on deeper routes and made the most of it after catching said target. Of course, Gabriel has a new offensive coordinator and Williams has a new coaching staff altogether, so Wallace has the best combination of the three with respect to statistical reliability and structural continuity.

In this context, the flip side is also informative. Among the Top 10 in True aDOT, there also exist the usual suspects vis-a-vis YAC: Robby Anderson’s True aDOT ranked 3rd, but his True YAC ranks 118th. Similarly, Mike Evans True aDOT ranked 5th, but his True YAC ranks 130th, Marquise Goodwin’s rankings were 6th and 108th, Roger Lewis’ were 7th and 93rd, Josh Bellamy’s were 8th and 96th, and Terrelle Pryor’s were 10th and 128th. Analogous to the previous paragraph, this means that Sammie Coates (No. 1 True aDOT, No. 34 True YAC), J.J. Nelson (2nd, 35th), DeSean Jackson (4th, 33rd), and Will Fuller (9th, 43rd) are the outliers. But, as before, these four have to be pared down further based on their situations heading into 2017. Coates is affected by Martavis Bryant’s return from the cloud and Jackson is affected by switching teams (although his new offense also loves the deep ball). That leaves Nelson and Fuller as the True aDOT WRs that are also respectable with respect to True YAC.

DT : IR :: TL : DR

WR YAC takes eight times longer to stabilize than WR aDOT (aka air yards) and twice as long as TE YAC. This suggests that, when you hear YAC cited during an NFL broadcast, your statistical bullshit detector should hit DEFCON 1. Instead, our search for “true” WR skill should focus on players that bridge the gap between the two “true” stats. Heading into 2017, that means Mike Wallace, J.J. Nelson, and Will Fuller (and maybe DeSean Jackson).