Krishnamoorthi Jayakumar

``` import re key = "nue_cc" crit_str = "(reco_zenith >= 0) & (reco_z >= 500)" for variable_name in ['reco_z','reco_zenith']: # Using word boundary \b to replace whole words only crit_str...

Hi, I have raised a pull request for this issue. It would be great if you could review the pull request. Thanks.

1. The second and third hyperlinks are not working (maybe moved/removed). 2. I don't find any duplicate between [stats.py](https://github.com/icecube/pisa/blob/master/pisa/utils/stats.py) and [likelihood_functions.py](https://github.com/icecube/pisa/blob/master/pisa/utils/likelihood_functions.py) 3. Functions in `stats.py` (`barlow_llh()`, `poisson_gamma()`) depend on the...