G RshYd RshTD RecYd RecTd FPT
-------------------------------------------------------
Running Back A 16 1229 4 535 2 212
Running Back B 16 1368 8 182 0 203
Just from looking at the
lines of numbers, you can get a mental picture of each of these
two backs. And the images you get are very different.
Back A has a relatively low TD total, so maybe he gets
removed at the goal line. That, together with the high receiving totals,
paint a picture of a small, quick, and shifty back. Back B, on the
other hand, gets it into the end zone more, but doesn't appear to be a
dynamo with the hands. He has the look of a big bruiser.
Back A is Charlie Garner 1999. Back B is Eddie George 1996. Their fantasy production was very similar, but they achieved it in very different ways. You might say that they produced at similar levels, but that their production had a different shape.
Anyone who has read much of the work of baseball writer Bill James is familiar with a toy he developed called similarity scores. Essentially, the idea is to take two players' seasons and put a number on the pair that gives you an idea of how similar they are. A similarity score of 1000 means the two seasons were identical, a score of 0 would indicate two seasons that were completely and totally different. For a complete look at (a slight modification of) his system, go here.
I thought it might be fun to apply the same idea to football. So I devised the following quick formula.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT ------------------------------------------------------------------ Garner Charlie 1999 16 1229 4 535 2 212 Watters Ricky 1999 16 1210 5 387 2 202
Note that the system imposes separate penalties for differences in rushing and receiving. So if Back A had 1000 rushing yards and 600 receiving yards, and Back B had 1500 rushing yards and 100 receiving yards, the two would get a very low similarity score despite having identical total yardage. In other words, the system tries to measure not only similarity in the level of production, but also in the shape of the production.
I took six running backs and four wideouts from 1999, and found the 15 closest matches for each. I tried to select players who had rather distinctive profiles. Mostly this is just for fun, but we may learn a few things along the way.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM -------------------------------------------------------------------------- Davis Stephen 1999 14 1405 17 111 0 254 1000 Warren Chris 1995 16 1346 15 247 1 255 773 Allen Terry 1996 16 1353 21 194 0 281 773 Bettis Jerome 1996 16 1431 11 122 0 221 762 Smith Emmitt 1999 15 1397 11 119 2 230 732 Martin Curtis 1995 16 1487 14 261 1 265 724 Means Natrone 1994 16 1350 12 235 0 231 721 Smith Emmitt 1998 16 1332 13 175 2 241 712 Hampton Rodney 1992 16 1141 14 215 0 220 686 Rhett Errict 1995 16 1207 11 110 0 198 681 Smith Emmitt 1994 15 1484 21 341 1 315 676 Watters Ricky 1996 16 1411 13 444 0 264 671 Davis Terrell 1997 15 1750 15 287 0 294 660 Stewart James 1999 14 931 13 108 0 182 642 George Eddie 1996 16 1368 8 182 0 203 636Davis is at the top in bold for reference. The last column, SIM, lists the similarity score between Davis 1999 and the given player.
Note that even the most similar seasons to Davis' aren't particularly similar. Let's see what these guys looked like the next year. I threw out Stewart 99 and Emmitt 99 (because their "next year" hasn't happened yet), and I averaged the remaining 12 players. Here's the summary.
|---- Similar Year -----------|------ The Next Year --------| RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT ----------------------------------------------------------- 1388 14 234 0 249 1202 9 196 1 202On the left, under "Similar Year," you see the averages of the players who were similar to Davis. Overall, a pretty good match, but not quite perfect. The composite "similar to Davis" back had fewer rushing TDs, but more receiving, so his overall fantasy production looks about the same.
The following year, these guys lost a good bit of their value -- particularly in the form of touchdowns -- and this should not come as a surprise to anyone who read my correlation coefficient article. Still very productive the next year, but a decent drop in value. If I really wanted to do this right, I would've factored age into the similarity score, but I haven't gotten around to doing that yet.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM -------------------------------------------------------------------------- Dunn Warrick 1999 15 616 0 589 2 133 1000 Johnson Anthony 1992 15 592 0 517 3 129 922 Anders Kimble 1997 15 397 0 453 2 97 823 Murrell Adrian 1995 15 795 1 465 2 144 819 Barber Tiki 1999 16 258 0 609 2 99 791 Byars Keith 1991 16 383 1 564 3 119 791 Murrell Adrian 1999 16 553 0 335 0 89 762 Kirby Terry 1996 14 559 3 439 1 124 757 Fletcher Terrell 1996 16 282 0 476 2 88 757 Lee Amp 1995 16 371 2 558 1 111 752 Bennett Edgar 1994 16 623 5 546 4 171 745 Alstott Mike 1996 16 377 3 557 3 129 725 Kirby Terry 1995 16 414 4 618 3 145 715 Centers Larry 1998 16 110 0 559 2 79 712 Byars Keith 1992 15 176 1 502 2 86 707 |---- Similar Year -----------|------ The Next Year --------| RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT ----------------------------------------------------------- 423 2 521 2 118 445 3 409 2 112As you can see, Dunn's comps held their value fairly well. But that's easier to do if your value is low to start with.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM -------------------------------------------------------------------------- Garner Charlie 1999 16 1229 4 535 2 212 1000 Watters Ricky 1999 16 1210 5 387 2 202 887 Staley Duce 1999 16 1273 4 294 2 193 858 Kaufman Napoleon 1997 16 1294 6 403 2 218 842 Anderson Jamal 1996 16 1055 5 473 1 189 822 Dunn Warrick 1997 16 978 4 462 3 186 808 Staley Duce 1998 16 1065 5 432 1 186 807 George Eddie 1998 16 1294 5 310 1 196 795 Dillon Corey 1999 15 1200 5 290 1 185 783 Williams Harvey 1994 16 983 4 391 3 179 775 Heyward Craig 1995 16 1083 6 350 2 191 775 Bennett Edgar 1995 16 1067 3 648 4 214 773 Thomas Thurman 1993 16 1315 6 387 0 206 763 Faulk Marshall 1997 16 1054 7 471 1 201 761 Smith Robert 1998 14 1187 6 291 2 196 757 |---- Similar Year -----------|------ The Next Year --------| RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT ----------------------------------------------------------- 1125 5 420 2 196 1026 5 338 2 174Note that Garner was a little bit better than most of his comps. Also note that his comps were able to come close to duplicating their numbers the following year. Again, that's to be expected of high-yardage, low-TD backs.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM -------------------------------------------------------------------------- Levens Dorsey 1999 14 1034 9 573 1 221 1000 Watters Ricky 1992 14 1013 9 405 2 208 876 Faulk Marshall 1997 16 1054 7 471 1 201 839 Davis Terrell 1995 14 1117 7 367 1 196 796 Williams Harvey 1995 16 1114 9 375 0 203 791 Watters Ricky 1993 13 950 10 326 1 194 785 Hampton Rodney 1991 14 1059 10 283 0 194 783 Anderson Jamal 1996 16 1055 5 473 1 189 780 Faulk Marshall 1995 16 1078 11 475 3 239 769 Parmalee Bernie 1995 16 878 9 345 1 182 768 Watters Ricky 1997 16 1110 7 440 0 197 766 Thomas Thurman 1996 15 1033 8 254 0 177 760 Staley Duce 1998 16 1065 5 432 1 186 754 Faulk Marshall 1994 16 1282 11 522 1 252 751 Thomas Thurman 1994 15 1093 7 349 2 198 749 |---- Similar Year -----------|------ The Next Year --------| RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT ----------------------------------------------------------- 1064 8 394 1 201 940 7 364 2 180Again, nice results. The Levens comps held their value well.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM -------------------------------------------------------------------------- Martin Curtis 1999 16 1464 5 259 0 202 1000 Bettis Jerome 1993 16 1429 7 244 0 209 915 George Eddie 1998 16 1294 5 310 1 196 860 Thomas Thurman 1993 16 1315 6 387 0 206 832 George Eddie 1996 16 1368 8 182 0 203 824 Dillon Corey 1999 15 1200 5 290 1 185 803 George Eddie 1997 16 1399 6 44 1 186 800 Staley Duce 1999 16 1273 4 294 2 193 797 Smith Robert 1997 14 1266 6 197 1 188 770 Johnson Anthony 1996 16 1120 6 192 0 167 765 Smith Emmitt 1997 16 1074 4 234 0 155 763 Kaufman Napoleon 1997 16 1294 6 403 2 218 753 Watters Ricky 1999 16 1210 5 387 2 202 749 Warren Chris 1994 16 1545 9 323 2 253 748 Murrell Adrian 1996 16 1249 6 81 1 175 744 |---- Similar Year -----------|------ The Next Year --------| RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT ----------------------------------------------------------- 1305 6 236 1 196 1122 7 238 1 184Same story as many of the above. An increase in TDs offsets a decline in yardage.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM -------------------------------------------------------------------------- Wheatley Tyrone 1999 16 936 8 196 3 179 1000 Alstott Mike 1999 16 949 7 239 2 173 912 Anderson Jamal 1997 16 1002 7 284 3 189 893 Allen Terry 1999 16 896 8 125 1 156 885 Murrell Adrian 1998 15 1042 8 169 2 181 884 Alstott Mike 1998 16 846 8 152 1 154 873 Thomas Rodney 1995 16 947 5 204 2 157 871 Brown Gary 1993 16 1002 6 240 2 172 855 Smith Antowain 1997 16 840 8 177 0 150 853 Allen Terry 1994 16 1031 8 148 0 166 839 Bates Mario 1995 16 951 7 114 0 149 832 Rhett Errict 1999 16 852 5 169 2 144 825 Thomas Thurman 1995 14 1005 6 220 2 171 824 Edwards Robert 1998 16 1115 9 331 3 217 813 Thomas Thurman 1996 15 1033 8 254 0 177 813 |---- Similar Year -----------|------ The Next Year --------| RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT ----------------------------------------------------------- 970 7 196 1 166 884 6 196 1 146Wheatley's comps held up well also. I was expecting a bigger drop from them.
Now we take a look at some receivers. There are a few results here that surprised me.
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM
--------------------------------------------------------------------------
Jeffers Patrick 1999 15 16 0 1082 12 182 1000
Galloway Joey 1997 15 72 0 1049 12 184 956
Rison Andre 1992 15 0 0 1119 11 178 944
Pickens Carl 1994 15 0 0 1127 11 179 940
Carter Cris 1998 16 -1 0 1011 12 173 936
Carter Cris 1997 16 0 0 1069 13 185 936
Smith Rod 1997 16 16 0 1180 12 192 931
Bruce Isaac 1999 16 32 0 1165 12 192 931
Conway Curtis 1995 16 77 0 1037 12 183 927
Pickens Carl 1996 16 2 0 1180 12 190 924
Sharpe Shannon 1996 15 0 0 1062 10 166 922
McCaffrey Ed 1998 15 0 0 1053 10 165 918
Rison Andre 1991 16 -9 0 976 12 169 915
Mathis Terance 1998 16 -6 0 1136 11 179 912
Freeman Antonio 1997 16 14 0 1243 12 198 899
|---- Similar Year -----------|------ The Next Year --------|
RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT
-----------------------------------------------------------
13 0 1096 12 180 11 0 1110 10 170
Jeffers' production was very touchdown-heavy last year, so I was expecting
a significant dropoff in production by his clones. Didn't happen. Now
check this one out...
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM
--------------------------------------------------------------------------
Smith Jimmy 1999 16 0 0 1636 6 200 1000
Moore Rob 1997 16 0 0 1584 8 206 914
Irvin Michael 1991 16 0 0 1523 8 200 884
Ellard Henry 1994 16 -5 0 1397 6 175 878
Irvin Michael 1995 16 0 0 1603 10 220 864
Brown Tim 1999 16 4 0 1344 6 171 852
Thigpen Yancey 1997 16 3 0 1398 7 182 850
Brown Tim 1997 16 19 0 1408 5 173 847
Irvin Michael 1992 16 -9 0 1396 7 181 846
Fryar Irving 1997 16 0 0 1316 6 168 840
Bruce Isaac 1996 16 4 0 1338 7 176 819
Irvin Michael 1993 16 6 0 1330 7 176 814
Reed Jake 1996 16 0 0 1320 7 174 812
Perriman Brett 1995 16 48 0 1488 9 208 812
Thigpen Yancey 1995 16 1 0 1307 5 161 805
|---- Similar Year -----------|------ The Next Year --------|
RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT
-----------------------------------------------------------
5 0 1416 7 185 4 0 938 5 124
This is probably just a coincidence. I repeat: this is probably just a
coincidence.... but, a large number of receivers who had seasons similar
to Smith's 1999 fell off a cliff the next year. In fact, if Smith's
numbers decline by the same percentage as his comps did, he projects
to about 1100 yards and 4 TDs. I'm not saying that's going to happen,
but it's worth noting.
A couple more for you to peruse at your leisure:
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM
--------------------------------------------------------------------------
Sanders Frank 1999 16 0 0 954 1 101 1000
McDuffie O.J. 1997 16 0 0 943 1 100 995
Graham Jeff 1999 16 0 0 968 2 109 963
Ellard Henry 1993 16 18 0 945 2 108 957
Irvin Michael 1998 16 1 0 1057 1 112 948
Ellard Henry 1996 16 0 0 1014 2 113 940
Blades Brian 1991 16 17 0 1003 2 114 937
Sanders Frank 1995 16 1 0 883 2 100 934
Brisby Vincent 1995 16 0 0 974 3 115 930
Morton Johnnie 1998 16 11 0 1028 2 116 928
Chrebet Wayne 1996 16 0 0 909 3 109 918
Slaughter Webster 1991 16 0 0 906 3 109 916
Slaughter Webster 1994 16 0 0 846 2 97 916
Dawkins Sean 1998 15 0 0 823 1 88 915
Carrier Mark 1995 16 -4 0 1002 3 118 914
|---- Similar Year -----------|------ The Next Year --------|
RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT
-----------------------------------------------------------
3 0 949 2 108 2 0 684 4 94
LastName FirstName Year G RshYd RshTD RecYd RecTd FPT SIM
--------------------------------------------------------------------------
Toomer Amani 1999 16 4 0 1183 6 155 1000
Martin Tony 1998 16 0 0 1181 6 154 997
Martin Tony 1995 16 0 0 1224 6 158 978
Reed Jake 1997 16 0 0 1138 6 150 976
Slaughter Webster 1989 16 0 0 1236 6 160 972
Irvin Michael 1994 16 0 0 1241 6 160 969
Brown Tim 1993 16 7 0 1180 7 161 967
Coates Ben 1994 16 0 0 1174 7 159 964
Ismail Qadry 1999 16 4 0 1105 6 147 961
McCardell Keenan 1997 16 0 0 1164 5 146 959
Smith Rod 1998 16 63 0 1222 6 165 951
Freeman Antonio 1999 16 -2 0 1074 6 143 943
Morton Johnnie 1999 16 0 0 1129 5 143 941
Barnett Fred 1992 16 -15 0 1083 6 143 941
Barnett Fred 1994 16 0 0 1127 5 143 940
|---- Similar Year -----------|------ The Next Year --------|
RshYd RshTD RecYd RecTD FPT RshYd RshTD RecYd RecTD FPT
-----------------------------------------------------------
5 0 1179 6 154 2 0 911 6 128