Solution to error message above
- Upgrade pip (https://stackoverflow.com/questions/15221473/how-do-i-update-pip-itself-from-inside-my-virtual-environment )
on Windows
python -m pip install --upgrade pip
2. Download unofficial window binaries from http://www.lfd.uci.edu/~gohlke/pythonlibs/ then install the local wheel using pip
C:\Users\Ajay>pip install statsmodels-0.8.0-cp34-cp34m-win_amd64.whl
3 Other more complicated ways- above two methods work best for me
https://blogs.msdn.microsoft.com/pythonengineering/2016/04/11/unable-to-find-vcvarsall-bat/
https://stackoverflow.com/questions/2817869/error-unable-to-find-vcvarsall-bat
DECISION STATS 