Goose Chase - Week 1

  Posted 9/6 by Chase Stuart, Exclusive to Footballguys.com

Fantasy football researchers spend hundreds of hours every summer creating their projections in the hopes of winning their fantasy league(s). Something that's always intrigued me is the 800-lb gorilla in the room that no one ever adequately answers: how should your projections change as the season goes on? Surely all your hard work in the offseason shouldn't be dismissed after one week…but when should it be dismissed?

Footballguys.com has Brandon Jacobs - a polarizing, first-time starting RB - projected to score 185.3 FPs this year, or 11.6 FP/G. Shaun Alexander, the once great fantasy star who showed signs of decline last season, is projected at 212.9 FP, or 13.3 FP/G. I don't think anyone would be shocked if Alexander finished in the top three this season, or outside the top fifteen. Similarly, projections for Jacobs are all over the map. Really, before the season starts, we don't know which Brandon Jacobs or Shaun Alexander will show up in 2007. We do know that Alexander (ADP 1.05) is considered the better fantasy RB than Jacobs (ADP 3.10), at least for now.

But what about after one week? What about after two, or three, or four weeks? If Jacobs scores 17 FPs this weekend against the Cowboys, while Alexander scores just 9 FPs against the Bucs, would that be enough to make Jacobs more attractive going forward? Surely Shaun Alexander owners would reject a straight-up 'Jacobs for Alexander' trade right now, but what about after our hypothetical week one result? Would the Alexander owners reject the trade if Jacobs is averaging 15 FP/G through three weeks, and Alexander is at just 11 FP/G after three weeks? Specifically, how much weight should we give to our preseason projections relative to the actual season-to-date results, when predicting the remainder of the season results?

It's a question I hope to answer in the first three installments of Goose Chase. I won't pretend that it's an easy question, or one that has a definitive answer. But I can promise you that I'll provide you a lot more than just a gut feeling. This week, we'll look at RBs and WRs. Next week, we'll examine QBs and TEs. Finally, in week three, I'll tweak the system a few times to see what different results we get.

From 2000-2006, Footballguys.com projected exactly 100 RBs to score 100 FPs or more in a season, using the standard scoring system of 1 point per 10 yards, 6 points per TD, and zero points per reception. With a sample that large, we can decipher how to use preseason projections and in-season results to predict remainder of season results. For example, in 2001, a rookie Travis Henry wasn't very good, but was expected to shoulder more of the load in 2002. Footballguys.com projected him to score 11.4 FP/G in '02, but in week one he exploded for 178 yards and 3 TDs against the Jets. While he wouldn't average 35.8 FP/G for the season, what would have been a good prediction for the rest of the year? It turns out he averaged 14.9 FP/G the rest of the year; so a formula of six parts preseason projections and one part week one projections would have predicted the right result. (6/7 * 11.4 + 1/7 * 35.8 = 14.9)

We can perform a regression analysis to figure out how much weight should be placed on the preseason projections and how much weight on the week one results, in order to predict the remaining fantasy points production. It's important to solve for the FPs for weeks 2-17 and not the full season data, otherwise we'll prejudice our results. Since we have a large sample of 100 RBs, we can be confident in the results of this analysis.

It turns out that the "correct" formula is 5.02 parts projections, and 1 part week one results. This feels about right to me. So if LaDainian Tomlinson (projected to average 20.2 FP/G) scores 15 FP this week, Steven Jackson(proj: 16.4 FP/G) would need to score 34 FPs in week one to make us indifferent as to which one we'd prefer the rest of the way. Laurence Maroney (13.1) would need to score 35.6 more FP than Tomlinson this week to make us project them equally for the rest of the year.

Below shows the breakdowns for the RBs through X weeks of the season:

It's worth noting that even after six weeks, preseason projections still matter more than the regular season results. Willie Green was projected to score 9.5 FP/G as a rookie, and was averaging just 2.1 FP/G through six games; he averaged 12.4 FP/G the rest of the way. In 2005, Tomlinson was averaging over 26 FP/G after six games, but scored only 160 FPs over his last ten games, much more in line with his projection of 18.6 FP/G. And preseason projections aren't worthless after eight weeks, either - they just become less and less important. Your remainder-of-season projections shouldn't be based off binary analysis: preseason projections don't either matter or don't. Rather, it's a sliding scale, where they become less and less valuable each week.

How do things look at wide receiver? The table below displays the results of the same type of regression analysis, performed on the 197 WRs projected to score 80 or more FPs.

Preseason projections seem to matter a bit more here, and that's not terribly surprising. Wide receivers get fewer targets than RBs get carries and targets, which means a really good or bad start could be the result of a small sample. Therefore, you should be less quick to give up on your wide receivers.

Let's go through a few examples again. How about Chad Johnson and T.J. Houshmandzadeh? Johnson (189.4 projected FPs, 11.8 FP/G) is projected to be quite a bit better than his Bengals counterpart (169.7 projected FPs, 10.6 FP/G), and I don't know any Chad Johnson owner that would make a straight-up swap. After just one game, Houshmandzadeh would need to score 8 more FPs than Johnson to make you consider them equal. Does that sound right? On one hand, it's easy to say that there's nothing that could happen in one game to make you change your mind. And you might be right. But remember that in 2001, Randy Moss was projected to be the top WR by just about everyone, coming off a ridiculous 1437/15 season. He had just 28 yards in week one, and 2001 ended up being the worst season of his young, four-year career.

In stark contrast, though, is Marvin Harrison of the same year. He would gain just 35 yards in week one, but would finish the season with over 1500 yards and 15 TDs. So always remember not to trade your studs after just a bad week.

You shouldn't even give up on your studs after five games, unless they've tanked. Once again, remember we're dealing with a continuum, and there's no on/off switch as to when the regular season starts to matter and the preseason projections stop. But even after five games, the preseason projections still matter a bit more than the regular season projections. Lee Evans in 2005 is a good example; he had just 3.4 FP/G through five games, despite being projected to score 8.3 FP/G. He would average 9.4 FP/G the rest of the year. Remember our 2001 Randy Moss, who was bad in week one? Well he wasn't good in weeks two, three, four or five, either. But in the last 11 games he would haul in 9 TDs and 900+ receiving yards, nearly doubling his per-game output from the first five weeks.

So what's it all mean? The two tables above can be a rough guide for you when thinking about making trades or deciding who to start in a given week. But they should just be used as a guide, and not as the formula to end all formulas.

One thing to remember is that strength of schedule matters. When using large samples, strength of schedule (and other random variables) aren't relevant to the analysis. However, strength of schedule matters a lot when we're analyzing our current players. If Jon Kitna does poorly against the Raiders this weekend, you'll want to give him more slack than if whoever starts for Oakland is inept against the Lions pathetic pass defense.

Additionally, not all fantasy points are created equally. A player with a couple of TDs and not a lot of touches is probably going to disappoint in the future. Likewise, if Marion Barber III has 240 total yards through the first three weeks of the season but no scores, that's probably a better sign than if he had 80 total yards and three scores. Along the same lines, yards per carry, touchdowns, targets and yards are all relevant information to have, and tell you more about a player than merely fantasy points per game.

Finally, there are some times when you can just throw out the preseason projections. Obviously if a player gets hurt that changes everything, but there are subtler events that could cause a revision. If we see Torry Holt look great in week one, he'll deserve a big spike because he's presumably healthy. The same goes with Thomas Jones. If Tatum Bell, Marshawn Lynch or Adrian Peterson get 25 carries this week, and there's an indication that there's no RBBC on those teams, then an bump is in order. For established players, this won't be the case. With younger players or guys on new teams, we've got less reason to be confident in our projections. In those cases, it makes sense to weigh what you see this year a bit more than when watching Peyton Manning.

As always, send any and all questions and comments to stuart@footballguys.com.