or maybe pitchers got better at throwing them? (because they can throw harder, as a group?)

Jeremy, a question and a clarification.

What's the scale on red and blue here? How much did the called strike rates change?

Secondly, I showed that the fastball velocities recorded by BIS were rising, and this was still true independent of their increasing classification of cutters. However, I've not seen the same thing in the PITCHf/x data. I've not studied it as closely for the effect as I did with the BIS data, so I'm not ready to draw any conclusions, but I'm not comfortable considering it established fact that fastball velocities are going up. I'm skeptical that it's occurring to the extent that the BIS data on Fangraphs indicates. I don't have a final conclusion on the matter, though.

Actually, I should qualify my previous comment a bit. I have seen an increase in fastball velocity in PITCHf/x data, and it's possible that the BIS data and PITCHf/x data are consistent in the size of the effect they see. I probably shouldn't have said anything given that I'm still looking into it. I just got a little uncomfortable with the certainty in the sentence referencing my previous work. The certainty was not unjustified based on what I had written and not necessarily disproved by anything I've found since. I'm just skeptical by nature and this is something I'm still looking at.

But I also know that I've given BIS grief over some of their stats lately, and it wouldn't be fair for me to do the same here because I don't have solid conclusions yet.

Mike, I didn't really put much time into finding the strike zone probabilities on this one, so I'm not comfortable with any findings. The magnitude of change was large enough to make me wonder whether I did something wrong.

Sorry if I misrepresented the findings in your article. Anyway, whether fastball velocities are rising or not, I'm rather certain that there are more hard throwers this year than in the past.

Why is the middle of the strike zone pink? Were there pitches down the middle that were called strikes this year but balls last year?

I think the answer is clearly the MLB finally decided to get rid of the juiced ball in order to "show" how effective their drug testing is making the MLB clean again.

Anyone who reads about the Sillyball at High Boskage Houses website, plus the lengthly research on how PED could not have been the cause of inflated offense, would agree. Before you scoff, the site is run by Eric Walker of Sinister Firstbaseman fame.

Jeremy,

Where is your data from that created the strike zone graph above? I like it and was wondering if you could point me to the data used.

Thanks,

Scott Sabol