See lesson posted at https://melindahiggins2000.github.io/N736Fall2017_lesson05/lesson05_dataWrangling.html
Github repo for Lesson 05 at https://github.com/melindahiggins2000/N736Fall2017_lesson05
Copyright © Melinda Higgins, Ph.D.. All contents under (CC) BY-NC-SA license, unless otherwise noted.