Article: Do Instant Draft Grades Mean Anything?

[listopencil]

Do Instant Draft Grades Mean Anything?
Not Really
5/11/2010 3:30 PM ET By JJ Cooper

Last month you could find draft grades everywhere on the Internet (including this site). Everyone loves to read rankings, especially if they give your team an A or a B+. But do they mean anything? The old adage is it takes three or four years before you can really evaluate an NFL draft. But are the initial draft grades just for entertainment purposes or is their some value to them?

-snip-


How The Experts Did?

I'll defer to my friend, stats expert Greg Stonerock, my partner in putting together this analysis, for the following paragraph explaining how we analyzed the data.

We used a Spearman test to compare the two sets of rankings, and it looks like the draft experts did a pretty miserable job of predicting how the drafts would turn out. The Spearman test shows a correlation coefficient of .117. A coefficient of 1 (or -1) would mean post-draft grades predict NFL success perfectly; a 0 would mean the prediction is worthless. The correlation of .117 is so close to 0 that the grades cannot be considered any sort of predictor of future success. In fact, if you ranked drafts completely at random, you would get a .117 (or farther from 0) more than half the time. (52.3% of the time, to be precise.)

http://nfl.fanhouse.com/2010/05/11/d...usspor00000002


2005:

Team 	AP1 	PB 	ST 	Car AV 	G 	Then 	Now 	Best Player 	Score
Dallas 	4 	7 	19 	197 	467 	A 	A 	DeMarcus Ware 	166
Tennessee 	1 	1 	19 	162 	566 	B- 	A 	Michael Roos 	108
San Diego 	1 	3 	13 	139 	330 	B 	A 	Shawne Merriman/Vincent Jackson 	101.5
Philadelphia 	0 	2 	18 	157 	451 	B+ 	A 	Trent Cole 	95.5
San Francisco 	0 	1 	19 	127 	490 	B 	A- 	Frank Gore 	93
New England 	0 	2 	18 	150 	333 	B- 	A- 	Logan Mankins 	92.5
St. Louis 	0 	0 	23 	112 	472 	C 	A- 	Alex Barron 	87
Atlanta 	0 	1 	15 	123 	392 	B- 	A- 	Roddy White 	84
Seattle 	1 	3 	13 	99 	259 	C 	A- 	Lofa Tatupu 	82.5
Green Bay 	0 	3 	12 	111 	313 	B- 	A- 	Nick Collins/Aaron Rodgers 	81
Miami 	0 	1 	14 	98 	302 	B 	B+ 	Ronnie Brown 	71
Carolina 	0 	0 	10 	87 	326 	B- 	B+ 	Thomas Davis 	59.5
New York Jets 	0 	1 	10 	81 	323 	C- 	B+ 	Kerry Rhodes 	59.5
Baltimore 	0 	1 	11 	77 	287 	B+/A- 	B 	Jason Brown 	54.5
Tampa 	0 	0 	11 	80 	302 	B 	B 	Barrett Rudd 	52.5
Jacksonville 	0 	0 	8 	88 	321 	C 	B 	Khalif Barnes 	52.5
New York Giants 	1 	1 	8 	81 	237 	C/C+ 	B 	Justin Tuck/Brandon Jacobs 	52
Chicago 	0 	0 	11 	87 	272 	B 	B 	Kyle Orton 	52
Pittsburgh 	0 	0 	10 	86 	278 	B-/B 	B- 	Heath Miller 	49
Oakland 	0 	0 	11 	64 	274 	B 	B- 	Kirk Morrison 	45
Indianapolis 	0 	0 	9 	57 	325 	C 	B- 	Kelvin Hayden 	44.5
New Orleans 	1 	2 	7 	64 	207 	C+ 	C+ 	Jamaal Brown 	43.5
Cleveland 	0 	1 	8 	72 	220 	B/B+ 	C+ 	Braylon Edwards 	35.5
Houston 	1 	1 	6 	52 	229 	C+ 	C+ 	C.C. Brown 	35
Arizona 	0 	0 	6 	58 	291 	A- 	C 	Antrel Rolle 	33
Denver 	0 	0 	8 	57 	270 	C- 	C 	Chris Myers 	30.5
Kansas City 	0 	0 	9 	36 	232 	B- 	C 	Derrick Johnson 	26.5
Washington 	0 	0 	6 	57 	132 	C 	C 	Jason Campbell 	15
Cincinnati 	0 	0 	5 	51 	208 	B-/B 	D 	Chris Henry 	14
Minnesota 	0 	0 	3 	29 	219 	A- 	D 	Troy Williamson 	12
Buffalo 	0 	0 	1 	26 	206 	C 	F 	Roscoe Parrish 	5.5
Detroit 	0 	0 	2 	26 	150 	B 	F 	Shaun Cody 	5.5

2006:

Team  	AP1  	PB  	St  	Car AV  	G  	Then  	Now  	Best Player  	Score
NY Jets 	2 	4 	11 	110 	394 	B 	A+ 	Nick Mangold/D'Brickishaw Ferguson 	120
Denver 	1 	4 	13 	149 	326 	B 	A+ 	Brandon Marshall/Elvis Dumervil 	116.5
Houston 	0 	5 	16 	135 	307 	B- 	A+ 	Mario Williams/DeMeco Ryans 	105
Green Bay 	0 	0 	17 	146 	425 	B 	A 	Greg Jennings 	95
New Orleans 	1 	1 	12 	140 	307 	B+ 	A 	Jahri Evans 	90
Indianapolis 	0 	2 	12 	123 	324 	C 	A- 	Joseph Addai 	89
Baltimore 	0 	1 	14 	93 	370 	B 	A- 	Haloti Ngata 	86
Buffalo 	0 	0 	15 	106 	331 	C 	B+ 	Kyle Williams 	84
Tennessee 	1 	2 	9 	102 	316 	B- 	B+ 	Cortland Finnegan 	84
San Francisco 	0 	1 	13 	82 	362 	B- 	B 	Vernon Davis 	79.5
Minnesota 	0 	0 	12 	98 	320 	C+ 	B 	Chad Greenway 	73
Chicago 	2 	2 	7 	89 	249 	C- 	B 	Devin Hester 	71.5
San Diego 	1 	3 	9 	92 	238 	B- 	B 	Marcus McNeill 	71.5
Philadelphia 	0 	0 	11 	96 	307 	B+ 	B 	Broderick Binkley 	65
Carolina 	0 	1 	6 	81 	323 	B 	B 	DeAngelo Williams 	54
Cleveland 	0 	0 	10 	78 	300 	B+ 	B- 	Kamerion Wimberly 	52.5
New England 	1 	1 	6 	59 	306 	B 	C+ 	Stephen Gostkowski 	49.5
Cincinnati 	0 	0 	11 	70 	225 	C 	C+ 	Domata Peko 	45
Jacksonville 	0 	1 	8 	92 	212 	C+ 	C+ 	Maurice Jones-Drew 	44
Arizona 	0 	0 	10 	63 	246 	A 	C+ 	Deuce Lutui 	41.5
Oakland 	0 	0 	9 	59 	258 	B- 	C 	Thomas Howard 	39.5
Kansas City 	0 	0 	9 	66 	227 	C+ 	C 	Tamba Hali 	38
Tampa Bay 	0 	1 	9 	54 	216 	C 	C 	Jeremy Trueblood 	35
NY Giants 	0 	0 	6 	58 	273 	C+ 	C 	Barry Cofield 	31
Seattle 	0 	0 	8 	48 	249 	B+ 	C 	Darryl Tapp 	30.5
Dallas 	0 	0 	3 	44 	315 	C+ 	C- 	Anthony Fasano 	29
Pittsburgh 	0 	0 	7 	68 	193 	B 	C- 	Santonio Holmes 	28
Washington 	0 	0 	7 	64 	209 	D+ 	C- 	Rocky McIntosh 	27
St. Louis 	0 	0 	5 	48 	266 	C+ 	C- 	Victor Adeyanju 	25.5
Detroit 	0 	0 	4 	37 	163 	C+ 	D 	Ernie Sims 	8
Atlanta 	0 	0 	1 	32 	166 	C 	F 	Jerious Norwood 	5.5
Miami 	0 	0 	1 	25 	185 	C 	F 	Jason Allen 	5.5

I was trying to save the layout for the 2005 and 2006 charts that were posted in the article. But I'm a lazy editor so I just threw it into a code box and it's still a bit messed up. Go to the article for a clearer chart.

[Binkythefrog]

In addition, football is very much a team sport and although individuals can perform well in some situations, if for example are a WR on a team with a terrible QB (say... Jamarcus Russell) you are going to look worse than how you may perform with a better QB. What if Marshall was drafted by the Raiders? It's quite possible he would be nowhere near to where he is now.

Its tough for any of these draft people to have any credibility. Kiper I think had credibility when he was the only game in town, but now that information and film is everywhere on prospects, their guess is just as good as ours.