ImportError: cannot import name 'factorial' from 'scipy.misc'

TL;DR: your statsmodels is too old for your scipy. scipy removed factorial from scipy.misc, so upgrade statsmodels to a release that no longer uses it, or pin an older scipy.

The error

ImportError: cannot import name 'factorial' from 'scipy.misc'

Fix it

1. Upgrade statsmodels:

   pip install -U statsmodels

   Expected: installs a release fixed for modern scipy.

2. Verify:

   python -c "import statsmodels; print(statsmodels.__version__)"

   Expected: imports cleanly.

3. Workaround if you cannot upgrade statsmodels: pin scipy below the removal:

   pip install "scipy<1.13"

   Expected: the old name exists again.

When this applies

Use this when import statsmodels raises this error with a recent scipy.

When it does not apply

If your own code imports factorial from scipy.misc, use math.factorial or scipy.special.factorial instead. If statsmodels is current, reinstall it.

Compatibility

statsmodels releases before the scipy-compat fix; scipy 1.13+ where scipy.misc.factorial is gone.

Root cause

scipy.misc was a grab-bag module that scipy emptied out over several releases; factorial moved to scipy.special long ago and the scipy.misc alias was finally deleted. statsmodels imported the old path, so the deletion broke it at import.

Edge cases

The same scipy.misc cleanup also removed imread, imsave, and comb; old statsmodels hit factorial first, but grep for scipy.misc imports when upgrading. Pinning old scipy can break packages that need new scipy.

GitHub issue statsmodels/statsmodels#5619 reports ImportError: cannot import name 'factorial' from 'scipy.misc' when importing statsmodels with a modern scipy. The verified resolution: scipy removed factorial from scipy.misc, so old statsmodels broke at import; the fix is upgrading statsmodels to a release that imports factorial from its new location (or pinning an older scipy as a workaround). Full thread: https://github.com/statsmodels/statsmodels/issues/5619