Wednesday, February 04, 2009

Accuracy analysis for 2008

My 2008 accuracy analysis is up on the Fifth Down! Check it out, Ranking the Rankings in Fantasy Football, 2008 and let me know what you think. Does my system make sense? Will you be thinking about this at all when you decide which rankings to look at next summer? What else would you like me to do with this?

If you're wondering which sites I looked at, here's a full list of all 23 sites in alphabetical order:

  • ADP (via FF Calculator)
  • Ask the Commish
  • CBS Sports
  • ESPN
  • Fantasy Hulks
  • Football Outsiders
  • Fantasy Football Nerd
  • Fantasy Football Sherpa
  • Fantasy Football Starters
  • Fantasy Football Trader
  • Fantasy Football Xtreme
  • FFToday
  • FFToolbox
  • Fantazzle Fantasy Sports Games
  • FootballDocs
  • FOX Sports
  • KFFL
  • Robocoach
  • Rotoworld
  • Sports Illustrated
  • SportsBuff
  • Yahoo! Fantasy Sports
My plans for the next few months include re-running the analysis with even more sites - I've already heard from a few sites that would like to see how they stack up - and I'd also like to take a look at this from a more historical perspective as well. Consider this my solicitation to fantasy football experts for their historical position rankings. The Wayback Machine can only be of so much help so if you happen to be have your rankings by position on hand for the past several years, send them my way; I'd love to run this same analysis on them.

In case you were wondering about the difference between how all of these sites actually did, you can see the battle was pretty tight based on the numbers for the Top 10 sites below. If you take the square root of the average number listed below, you would get the average amount of ranking spots "off" that each site was per player across all positions. I'm not showing that number here since I think knowing how "off" a site was per player is really most valuable when looking at specific positions, so you'll see that number in the details for the position rankings below. As you can read in my Fifth Down post, I ranked sites based on the sum of squared differences between rankings as averaged by the number of rankings for that position; the square root number is just being shown since I think it's easier for most of us to wrap our minds around than an obscure average number.

Top 10 sites across all positions:

1 Fantazzle 55.025
2 Yahoo 56.793
3 Fantasy Trader 57.033
4 ADP 58.293
5 FFToday 60.843
6 61.475
7 FOX Sports 63.205
8 ESPN 63.253
9 Ask the Commish 63.802
10 Rotoworld 64.815

Top 10 sites for QBs:

1 FFStarters 9.249
2 CBS Sportsline 9.309
3 Football Outsiders 9.463
4 ESPN 9.558
5 Robocoach 9.674
6 FFXtreme 9.742
7 FFToolbox 9.750
8 Fantasy Hulks 9.805
9 FOX Sports 9.887
10 Yahoo 9.907

Top 10 sites for RBs:

1 KFFL 5.638
2 Fantazzle 6.477
3 6.876
4 FFHulks 6.930
5 Yahoo 7.063
6 SI 7.123
7 FOX Sports 7.208
8 Fantasy Trader 7.293
9 FFDocs 7.334
10 FFToday 7.353

Top 10 sites for WRs:

1 Fantasy Trader 6.309
2 Yahoo 6.327
3 FFNerd 6.374
4 Fantazzle 6.414
5 6.421
6 FOX Sports 6.445
6 Rotoworld 6.445
8 FFToday 6.446
9 FFXtreme 6.470
10 Ask the Commish 6.501

Top 10 sites for TEs:

1 FantasyTrader 5.007
2 CBS Sportsline 5.018
3 ADP 5.249
4 FFStarters 5.555
5 Fantazzle 5.852
6 Yahoo 6.264
7 FFToday 6.655
8 Ask the Commish 7.519
9 7.595
10 Football Outsiders 7.736

A few things to note - you can see that on average the experts were far more "off" on their QB rankings than other positions. I attribute much of this to the Tom Brady effect. I left him in the rankings (and all other injured players) so to some extent it skews how off a ranking was on QBs, but it should have penalized all sites in roughly the same way.

I also think it's fascinating how close the WR predictions were - sites #4 through #9 are separated by less than 1 ranking spot. Very, very close.

Anyway, I could go on at great length here about all of the interesting things I found in looking at the details (like Laurence Maroney's difference in rankings single-handedly wrecked one site's RB rankings) but I think I'll pause and maybe give you all a breather from my rankings analysis talk.

Back soon with links to more content!


bigboid said...

Great analysis! I look forward to even more in the near future. I'm amazed at the consistency of FF Trader; I had not heard of them before this post, but they made the top ten lists for everyone but QBs, placed #1 in two lists, and finished #3 overall. That's a pretty strong record.

LesGrossman said...

Thanks Sara! We, at Fantazzle Fantasy Sports Games, appreciate all the hard work that went into this. I think this will be incredibly useful for the years to come and we hope to prove we weren't a fluke.

Ryan Parr
Fantazzle Fantasy Sports Games

Anonymous said...

Thanks bigboid. We're very happy with 3rd place among this competition. Apparently, don't ask us about QB's though b/c we don't know squat (23rd)! I'm anxious to see librarian's follow up to everyone's ranking in terms of longevity in the coming years. That'll begin to tell a clearer story in my opinion.

Rick Perkins.
Fantasy Football Trader.

Chris Migliaccio said...

Have you considered running a similar analsys using sites projections as opposed to their rankings? As we all know, rankings are useless without projections/tiers.

Anonymous said...

I absolutely love the work you do here! Amazing analysis!

Anonymous said...

Nice job. Thanks for putting in the hard work on this. I'm sure it wasn't easy compiling rankings from so many sites.

It's interesting to see that ADP placed #4 this year. Thanks for including it in the analysis. The long-term trends will be interesting to see as well.

Kevin Day
Fantasy Football Calculator

Anonymous said...

Is there anywhere we can go to see the actual pre-season rankings for some of these sites? (fantazzle, in particular)

Anonymous said... is a very well researched site. Curious why it wasn't included? Nice work overall though!

Anonymous said...

I'm going to second the projections...the actual projections really help when making decisions...

Anonymous said...

Seconding the thought that you should do this with projections...that'd be so awesome.