According to data provided by FanGraphs, Votto and Bruce rank second and fourth, respectively, among the most disciplined hitters in the game. For the record, Dexter Fowler tops the rankings with a "good decision percentage" of 74.2.
So, some of you may be asking how does one measure plate discipline by "good decision percentage?" That's an excellent question. Basically, good decision percentage is based on the average between the percentage of pitches correctly swung at inside the strike zone and the percentage of pitchers correctly not swung at outside of the strike zone. What it all really boils down to is how often a hitter swings at strikes as opposed to balls.
Votto's good decision percentage is 73.4 since 2012. Meanwhile, Bruce's is 72.9. Only Fowler and San Francisco's Brandon Belt have been better over that span.
The fact that Votto ranks high on this list didn't come as a surprise to me. However, I've got to admit that Bruce ranking so high certainly did. For starters, Bruce finished only one strikeout behind Pedro Alvarez for the National League lead in 2013. And he ranked just 15th in the league in walks last season as well. These two stats don't exactly signal plate discipline, but it does suggest Bruce comes up empty on a lot of his swings, even though he does a good job at only swinging at strikes.