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listopencil
05-12-2010, 05:32 PM
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/do-instant-draft-grades-mean-anything-not-really/?ncid=txtlnkusspor00000002


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
05-13-2010, 06:29 AM
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.