Just a quick post here with a correlation plot that I ran last night and wanted to share. The plot below shows a number of per game measures for running backs both in what you might call Year 1 and Year 2 (or Year N and Year N+1) and how they correlate year to year. You can see that the highest year to year correlations are grouped in carries and yards. Receiving numbers also share some correlation year to year. The interesting thing is that yards per carry has a pretty low correlation with itself (year to year) and also has a low correlation with the other measures.
Two additional thoughts:
- Year 2 TDs have a higher correlation with Year 1 Carries and Yards than with Year 1 Touchdowns. This is barely true, but true nonetheless.
- Same measure year to year correlations in descending order of correlation would go: Carries, Yards, Receptions, Receiving Yards, Rushing Touchdowns, Games Played, Receiving Touchdowns, Yards per Carry.