Today we'll have a quick look at what tRA can tell us beyond pitching.
Since calculating tRA requires expected outs and expected runs, we can utilise these figures to look at defense - in this case to check whether a missed play on defense is really worth the 0.8 extra runs we expect.
Determining xR-R and O-xO for the entire league... tells us nothing, because the resulting errors are tiny (which is good for tRA, but not good for what we're trying to do). Instead, we'll take the absolute value of xR-R and O-xO for each pitcher in, say, the AL last year, and sum that instead. We can then divide the two values and see how close we get to 0.8.
xR-R: 783.9926
O-xO: 978.7843
(xR-R)/(O-xO) = 0.80096
Well that's kinda neat.