FanGraphs Prep: Ups, Downs, and Rolling Averages
This is the seventh in a series of baseball-themed lessons we’re calling FanGraphs Prep. In light of so many parents suddenly having their school-aged kids learning from home, we hope is that these units offer a thoughtfully designed, baseball-themed supplement to the school work your student might already be doing. The first, second, third, fourth, fifth, and sixth units can be found here, here, here, here, here, and here.
Overview: A short unit centered on calculating rolling averages. Calculating the mean, median, and mode are fundamental concepts in math. But when we’re dealing with a dataset spread out over weeks, months, or years, simply calculating the average value for the entire dataset hides the data’s peaks and valleys. For a baseball player, those are the hot and cold streaks that everyone goes through during the season.
Learning Objectives:
- Identify and apply a rolling average.
- Explain how changing an interval affects interpretation.
- Consider the potential uses of a rolling average in baseball.
Target Grade-Level: 9-10
Daily Activities:
Day 1
Khris Davis famously hit .247 four seasons in a row from 2015–2018. If we take his total hits and total at-bats over those four seasons, it’s no surprise that his combined batting average is .247.
Year | At-bats | Hits | AVG |
---|---|---|---|
2015 | 392 | 97 | 0.247 |
2016 | 555 | 137 | 0.247 |
2017 | 566 | 140 | 0.247 |
2018 | 576 | 142 | 0.247 |
Total | 2089 | 516 | 0.247 |