New evidence that cold weather affects hitting

Chris Constanzio breaks offense down by game-time temperature, and finds some very interesting things. Walks and strikeouts are higher in cold weather, but home runs are down, even after adjusting for fewer balls in play.

Most astounding to me was that batting average on balls in play -- the DIPS measure -- is a full 20 points lower in very cold weather, as compared to very hot weather. Twenty points is huge, isn’t it?

Constanzio writes, "The most straightforward explanation for these findings is that the ball simply does not carry very well in cold weather. Batted baseballs are slowed down by air resistance in the heavy, dense air of cool April and October nights."

Thanks to “The Book” blog for the pointer. There’s some discussion there … Guy asks if day/night breakdowns have anything to do with it, which is a very good question.

Great little study!