How much can we really trust the data that MLB.com's Pitch f/x system (or similar systems such as Baseball Information Solutions) provides us? Several recent incidents make me wonder aloud how reliable the numbers really are.
First, as of late, Brett Myers has been having difficulty transitioning back into the rotation after closing last season. Quotes from Myers and Phillies pitching coach Rich Dubee suggest that Myers is throwing his cutter too much and relying on his fastball less [link]. However, if you examine tables at Fangraphs.com, which come from data collections made by BIS, Myers supposedly only throws a cutter 0.2% of the time.
In addition, Josh Kalk has wrote yesterday that he is having to do quite a bit of correcting in the data he siphons from the Pitch f/x system. He says that the errors are due in part to faulty cameras at several stadiums, Cincinnati in particular.
So, can we trust the data? It appears to me that we can only trust it after people like Kalk do their magic and make it more reliable, but I'd like some of the people who are more familiar with the analysis to chime in...
-----------------
By the way, nearly 1,500 searches have been done on Baseboogle since it launched a few months ago. I'm glad people are finding it to be a handy tool, so spread the word.
