Statistics book for Deep Learning recommendations

One of our members was looking for recommendations for a good, preferably free statistics book for ML.

The request comes from a lady with good programming back ground and solid linear algebra experience.

The main issues she has are in understanding some of the more data science type issues like population balancing, advanced data analysis techniques / issues etc which are relevant to ML.

Any suggestions welcome


Maybe Elements of Statistical Learning?

Fro the information theory concepts Elements of Information Theory by Cover, Thomas is a great book. I enjoyed it a lot