From Eli Ben-Porat at The Hardball Times on July 5, 2016:
We begin today’s story with MARS.
Not the delicious candy bar that sticks to your teeth; nor the planet that can grow Matt Damon’s potatoes. Rather, it is Multi-variate Adaptive Regression Splines, or MARS for short. MARS is a trademarked term, so the R or Python implementation is usually referred to as “earth.” Essentially, the MARS approach to regression improves upon basic multiple linear regression in three ways:
- It breaks apart each regression line into multiple formulae (for example, incremental fastball velocity below 94 mph has a different value curve than velocity above 94 mph).
- It prunes terms that aren’t beneficial to the model and pares it down to the important factors.
- It can uncover relationships between variables (say, location and velocity).
I’ll step away here and encourage you to read the Wikipedia article linked above for a more thorough explanation.
Read the full article here: http://www.hardballtimes.com/quantifying-pitcher-command/
Originally published: July 5, 2016. Last Updated: July 5, 2016.