Testing on Build Machines

There are currently several places that statsmodels is automatically built and tested against different dependency and Python versions and architectures. Check these logs periodically, make sure everything looks okay, and fix any failures:

Azure Pipelines <https://dev.azure.com/statsmodels/statsmodels-testing/_build?definitionId=1&_a=summary>_

The test coverage pages are here:

Coveralls <https://coveralls.io/github/statsmodels/statsmodels>_
codecov <https://codecov.io/gh/statsmodels/statsmodels>_

We use Codacy <https://app.codacy.com/project/josef-pkt/statsmodels/dashboard>_ to monitor code quality.