MLS: Starting Lineup Stability (2002)

2003, 2004 2005 I've finished another season of this time consuming study. Once again, I'm trying to find out if the number of starters an MLS team returns from the previous game has any impact on the team's preformance. Let's take a look at the yearly numbers, now with 2002 added in: PPG by number of returning starters 2002 2003 2004 2005 Total 4-7 1.10 0.76 1.18 1.21 1.09 8 1.49 1.53 1.71 1.30 1.48 9 1.39 1.26 1.43 1.39 1.37 10 1.60 1.62 1.14 1.55 1.49 11 1.14 1.29 1.27 1.35 1.28 Total 1.42 1.36 1.35 1.39 1.38 As you can see, there doesn't appear to be a distinct pattern. However, a low number of returning starters (RS) has equaled poor preformance, while teams returning all 11 starters has also done worse than average every year. 9 RS is basically the average number, so it's no surprise that it's right around the average PPG for this four year period. Both 8 and 10 RS have preformed better than average in 3 of 4 years. Hmm. We'll have to see if that holds up through all ten seasons. To further emphasize the yearly preformance vs the average PPG, here's a table that shows just that: Difference from Avg 2002 2003 2004 2005 Total 4-7 -0.32 -0.60 -0.17 -0.17 -0.29 8 0.07 0.17 0.36 -0.09 0.10 9 -0.03 -0.11 0.09 0.01 -0.01 10 0.18 0.26 -0.21 0.16 0.11 11 -0.28 -0.07 -0.07 -0.04 -0.10 Total 1.42 1.36 1.35 1.39 1.38 The 4-7 RS, you can definitely see the impact. The jury's still out on the others. Home/Away Impact 2002 2003 2004 2005 Total 4-7 -0.01 -0.17 0.01 -0.03 -0.05 8 0.04 0.05 -0.03 -0.05 0.00 9 0.00 -0.01 0.03 0.04 0.02 10 0.00 0.02 0.01 0.00 0.01 11 -0.04 0.00 -0.08 0.01 -0.03 Ttakes into account the number of home and away games for each category, and figures out the expected PPG based solely on that. Then, the overall yearly PPG for each category is subtracted from that. These numbers show that home field advantage has almost no impact. It would have to be an incredibly unbalanced set of games to actually be a factor, like the 2003 4-7 RS data (which adjusted would still be pretty low at 0.93). Finally, here's some overall data for the four years: Percentage of games in each category 2002 2003 2004 2005 Total 4-7 10% 8% 13% 10% 10% 8 15% 19% 15% 20% 18% 9 26% 31% 33% 28% 29% 10 35% 26% 25% 25% 27% 11 10% 11% 11% 14% 12% Home/Away/Overall RS by year 2002 2003 2004 2005 Total Home 9.10 9.19 8.99 9.15 9.11 Away 9.18 9.00 8.98 8.99 9.03 Total 9.14 9.09 8.98 9.07 9.07 2002 was interesting because teams made more changes in their starting lineups at home. And the overall number of changes was down, probably because of the World Cup and depth issues. With the larger rosters I would expect more changes this year than 2002.