remove statsmodels and add pandas to requirements

setup.py

@@ -18,7 +18,6 @@
     # the version across setup.py and the project code, see
     # https://packaging.python.org/en/latest/single_source_version.html
     version='0.1.0',
-
     description='Python tools for working with the AUROC',
     long_description=long_description,
 
@@ -47,10 +46,5 @@
     # your project is installed. For an analysis of "install_requires" vs pip's
     # requirements files see:
     # https://packaging.python.org/en/latest/requirements.html
-    install_requires=[
-        'pandas>=0.22.0',
-        'numpy>=1.12.1',
-        'scipy>=0.18.1',
-        'statsmodels>=0.8.0'
-        ]
+    install_requires=['pandas>=0.22.0', 'numpy>=1.12.1', 'scipy>=0.18.1']
 )