Thursday, September 10, 2009

A Graphical Representation of Consistency? We Try It...

This article by Jeff Zrebiec in The Baltimore Sun about the "streaky" Brian Roberts got me thinking about how to measure "streakiness". Roberts had never struck me as a streaky hitter but how could you easily tell? Hitters have good stretches and's part of baseball. Monthly splits tell some of the story but not all of it. That's when the idea of symmetry took hold.

Humans can easily identify symmetrical objects from uneven lopsided ones. It's genetic. That's how we judge beauty right?

So I just decided to measure the number of hits in each game and do a radar style graph to illustrate. For the Orioles, you can't get much more consistent than Nick Markakis' 2008 season. Here is is. Games counts go clockwise and hits come out from the center. As always, click through for a larger picture:

A couple of big outbursts throw off the balance a bit but this is about as balanced a graph as you're going to see from a good hitter.

For contrast, Melvin Mora's 2008. If you remember, Mora started pretty slow, exploded in late spring and turned out to have a pretty good year.

Fairly lopsided. That's pretty streaky.

One more from 2008, Aubrey Huff:

Pretty balanced overall with July and August being pretty killer to offset it a bit.

So now, Brian Roberts (so far) in 2009:

There are some gaps there...but really it's not that bad. You want to see real streakiness? Here's Luke Scott, 2009.

By comparison, Roberts looks fairly consistent. Sure, he has his hot streaks and cold but it's not crazy hot and cold. I would describe Roberts as many things before I would use the word "streaky".


Dave Mc said...

What a cool idea! Very pretty as well.

the wayward o said...