In this analysis, I am looking for two things: a change in the ranking order and a change in the slope of PPG distribution. A change in the ranking indicates that adding a point per catch will alter the order of player ranking. A change in slope of PPG distribution indicates a change in value of players at that position.
I examined the top 60 WRs from the past five years. I ignored those that played fewer than 8 games. I first ranked them by PPG and matched up their PPG with a point per reception. (PPG 2) I then sorted PPG 2 in a decending fashion to see how much the rankings changed. There was quite a bit of movement. Here is the table of data: Data Table The columns labeled "ppg rank" is the ranking of that WR by PPG without a point per catch. This shows you how much the order changes. For example, in 2001, the 22nd ranked WR by PPG was actually 12th by PPG 2. (pt/catch included) The biggest moves in the past 5 years were +13 and -14. Each year, there are about 7 to 12 players that move up or down by more than 5 spots. All this really means is that a handful of guys can move quite a few spots. My theory for the reason behind this: some WRs have high yards per catch (YPC) but don't catch many passes. These are your "deep threats". Some guys catch a ton of passes, but have low YPC, and thus low yards. These are your "possession WRs" Keyshawn Johnson and Hines Ward are two guys that moved up 11 and 10 spots when 1 pt. per catch was added. Bill Schroeder is a WR that dropped 8 spots in the 2001 rankings when 1 pt. per catch was added.
Next, I graphed the PPG distribution for each year. I subtracted a fixed amount from the PPG 2 data. Remember, all we are concerned with is a comparison of the slopes, not the values. By shifting the data, it is much easier to see the differences in slopes. Conclusion: The slopes are relatively close for the top 15 to 25 WRs, and then it drops off more sharply when a point per catch is included. In leagues that start only 24 total WRs, a point per catch doesn't affect WR value very much. However, in leagues that start at least 30 WRs, those top 15 to 25 WRs become much more valuable.
I examined the top 40 RBs over the past 5 years. The data was analyzed in the same fashion as the WR data. The biggest move upwards in the rankings was +14, by Amp Lee in 1998. Other large movers were Larry Centers in 2001 (+12) and 2000 (+10). There weren't as many big movers as with the WRs. On the downside, no player dropped more than 9 spots, with Antowain Smith falling 9 spots in 1999. One thing to consider - I only started with the top 40 in PPG. Larry Centers didn't make the top 40 in PPG in 1999, but would have jumped way over A. Smith in that year with 1 pt. per catch. I consider this to be a minor flaw in the analysis; one that doesn't mean much to our conclusions. Conclusion: This one is obvious, players like Centers, Lee, and Richie Anderson of 2000 can move up tremendously because their main role in the offense is to catch passes on 3rd downs. RBs like Antowain Smith of 1999 fall because they hardly catch any passes. Most of the main, featured backs don't move as much because their difference in receptions is more directly reflected in a difference of yards. RB's yards per catch doesn't vary as much as WRs (assumption), thus their rankings won't change as much when 1 pt per reception is added. However, this is still some shuffling. The exception is the 3rd down specialist.
Looking at the slope of the PPG distributions shows that adding 1 pt. per catch doesn't change the slope in nearly the same way that it does for WRs. The biggest differences are actually at the top, and that is attributed to Marshall Faulk. He's quite the exception, so we'll throw that out. Conclusion: Adding 1 pt. per catch doesn't change the value of RBs, but it does shuffle the order.
Quite honestly, I don't feel like looking at the TEs. I'll save that for another day. While what I learned may be obvious, it's good to have data to prove the point. Often, we assume certain correlations to be true without checking the data first.