Rather than looking at numbers, here we will look at some scatterplots to check the correlation of each number. I also put lines in each graph that represent the expected correlation, if it was perfect.
Here is the scatterplot of pitch velocity and FIP
In the next graphs, FIP serves as the horizontal axis. Here is the horizontal consistency (remember, the higher number means least consistent) versus FIP
Not much correlation here. There isn't a whole lot of variation overall (an obvious example being Bronson Arroyo who intentionally changes his arm angle throughout the game), and no real reason for why some of them were horrible starts and some of them were good.
What about just average horizontal release point (the higher the number means the further out)? Here, I assumed that there was no real value difference between lefties and righties, so I changed the negatives (righties) to positives.
Does vertical consistency matter more than horizontal consistency?:
What abut just vertical release point:
Certainly one could have used a different stat than FIP, but I think it tells us a little more about a start than SIERA or xFIP and I would have had to manually input all the kwERAs, which would have taken longer. Overall, I expected the consistency numbers to have a much better correlation than they did.
In conclusion, it doesn't really seem we can use any of these numbers to judge an individual start, at least from one pitcher to another. In future posts, I plan to look at some individual pitchers from start to start to see if these numbers have any correlation for individual pitchers.