Competence: Maths Level: Foundation
Every aspiring Data Scientist should get started by getting a solid background in Statistics. There are two books that can work as great 101 materials:
- Introduction to Probability by Joe Blitzstein and Jessica Hwang. It is now available at http://probabilitybook.net, with videos and other resources.
- Probability and Statistics by Morris H. DeGroot and Mark J. Schervish. It is called the Bible by some stats teachers.