Moving the Chains: BA/ERA/WHIP edition

Intuitively, we assume that it is harder to move up (or down) in the final week in batting average and ERA/WHIP. Here is a real life example from my American League.

Team A entered today with a 4.028 ERA while Team B had a 4.09 ERA. Team B's ERA breaks down as 1181 2/3 IP and 537 ER.

Let's assume that Team B had two starters going today and each starter threw seven shut-out innings. That would leave team B with 1195 2/3 IP and 537 ER. His ERA drops down to 4.042. He's significantly closed the gap on Team A. But he still hasn't gained that extra point.

I thought I'd do what I did yesterday and look at how much movement there was in batting average, ERA and WHIP in the last week of a Rotisserie season. This time, I'll examine how many points shifted in each category in the last week of the year, not counting points lost due to teams not making innings. Remember, this goes back to 1998, so the points are listed from 1998 to 2006, with a gap for 2002.

BA - 1 point gained/lost, 0, 1, 2, 1, 2, 2, 3
ERA - 0, 2, 2, 1, 1, 3, 7, 1
WHIP - 0, 0, 0, 2, 1, 1, 2, 0

That's more movement than I would have expected in all three of those categories. Of course, the typical scenario was when two teams were practically in lockstep to begin with and one team just happened to do a little better than the other one. This is particularly true in batting average...I had a year where I hit .346 in the last week to my opponent's .255 and stormed by him in average (and won the league by a point!). But you still have to be fairly close to even get to that point.

ERA/WHIP tend to be categories where teams lose points, as opposed to gaining points. A 6.00 ERA in the final week tends to be far more damaging than a 2.00 is beneficial. Sure, it depends on the number of innings you're putting up. But if you've accumulated the 1100+ IP that most contenders have by now, moving down is very, very difficult.

My final observation on this topic is that picking up a bunch of starters because everyone has clinched and will be swinging at total garbage doesn't make much sense. Yes, there will always be a few odd shutouts in the final weeks, and some game times around the two-hour mark. But you're still guessing which starters are going to go out and be great. Aaron Laffey was solid this week. Jair Jurrjens was terrible tonight. One would assume that Jurrjens would have been the better bet against a subpar Twins line-up but one would have assumed wrong. Don't assume your ERA/WHIP is safe if you grab some random assemblage of seven starters in the last week to make a wins play. You might get lucky and grab a wins point, but you might put ERA and WHIP points into play that you thought were safe at the beginning of the week.