Here’s how Bill Connelly defines it:
The concepts are pretty simple: Over time, you’re going to recover about 50 percent of all fumbles, but in a given year, you might recover 70 percent, or you might recover 30. The same goes with passes defensed; on average, you can expect to intercept about 22 percent of the passes you defense. (Passes defensed = interceptions + break-ups.) This is a bit mushier a concept … but over time a particularly butter-fingered year will be balanced by a sticky one.
The way I measure turnovers luck is pretty simple: how far were you from 50% with your fumble recoveries? How far were you from ~21-22% in your interceptions-to-breakups, offensively and defensively? By looking at broader numbers, we can basically create an expected turnover margin (called Adj. TO Margin below) and compare it to the real margin. The difference becomes your Turnovers Luck for the season. On average, a turnover is worth about five points in terms of field position value, so I take the difference between turnovers and expected turnovers, multiply it by five, divide it by games played, and voila: Turnovers Luck Per Game.
Georgia finishes as one of his top teams from last season, which shouldn’t come as a surprise to anyone who’s familiar with Georgia’s 2014 turnover margin. Similarly, there’s a huge swing from the 2013 luck tally. What you wonder about in the Dawgs’ case is how much of that luck came from changes in the defensive approach to turnovers and the emphasis on offense in avoiding turnovers at the quarterback position and how much was randomly generated. Sample size can be a bitch, you know.