Adding test_corr.py
Merge branch 'master' of https://github.com/AllenDowney/DataScience
Adding test_reg.py
Merge branch 'master' of https://github.com/AllenDowney/DataScience
Adding estimate1.py
Adding correlate1.py
Merge branch 'master' of https://github.com/AllenDowney/DataScience
Adding correlate1.py
classwork
fixing merge with allens correlate1