Does Projected Team WAR Actually Mean Anything?
I think it’s safe to say we lean pretty heavily on projections here. Now, it’s important to understand we’re all always kind of making projections. The Padres acquired Wil Myers on the basis of a positive internal player projection. When we think about our favorite teams adding, say, Dee Gordon or Nelson Cruz, we’re considering what we expect them to do in the season or seasons ahead. Our enthusiasm for the coming year is based in part on a mental projection of the quality of our team. We all project, and the only real difference is that, around here, we lean on the projections by Steamer and ZiPS, instead of doing things in our heads. FanGraphs makes things really easy. What do the projections think about next year? There’s a tab you can click on. It’s a starting point.
But while projections are handy, it’s only natural to wonder: do they matter? How important are they, actually, with regard to predicting the short-term future? Tons of people have tested individual player projections, but here we also include team projections, based on manually-updated depth charts, and if there’s error in each given player projection, how much error might we see with team projections as a whole? It’s a perfectly reasonable question. It can’t even be answered conclusively, yet. There’s not enough data in the FanGraphs post archive. But I can give you at least a little bit.