In part
one, I took at look at what effects walk rate. Part
two was Nick's general swing rates and splits - it seemed that he was swinging at fastballs outside the strike-zone at a much higher rate. Drilling down into that last issue a little deeper; here are the location charts of the fastballs that Markakis swung at, with the 2008 ones in red and the 2009 ones in blue:
You can see that the blue dots are more spread out than the red ones, and that there are more of them up and away. There are also a few more fastballs swung at in 2009 that were way outside the strike-zone. Putting the two together, with 2008 on top, you can see all the blue peaking out around the red:
He definitely expanded the zone against the pitch. Maybe Markakis was fooled more often due to the '09 fastballs being about half a mph faster than the '08 ones. Here's a chart for both years of swing rate versus fastball velocity.
Nope. He swung at his mid to upper 90s fastballs less than the previous season, but more at those low 90s pitches (which he saw more of). Comparing it to his contact rates at different velocities is interesting:
Was he able to make better contact with the higher velocity pitches because he was more selective with the ones he'd swing at - that is, he only swung when he thought that there was a better chance of hitting it? Alternately, did swinging at more lower velocity fastballs result in a worse contact rate there? Both are possible, I suppose.
In all honesty, I think that the change for fastballs is more an effect than a cause. That is, things were different and so they were different for fastballs because pitchers threw them in certain situations, and not that Nick had a much harder time identifying fastballs and so his swings rates went up because of that. In part four I'll look at what was going on in three-ball counts, when Nick was just one pitch away from taking a walk.
