Update PyMC version in Windows installation instructions

[zbraiterman]

Description of your problem

The PyMC installation instructions on https://www.pymc.io/projects/docs/en/stable/installation.html (running conda create -c conda-forge -n pymc_env pymc) found at did not work on my Windows 10 system. However, running ‘’ (specifying "pymc>=4"), as mentioned on the GitHub wiki (https://github.com/pymc-devs/pymc/wiki/Installation-Guide-(Windows)), seems to have worked.

If other Windows users have the same experience, I propose changing to pymc>=4.

Versions and main components

• PyMC/PyMC3 Version: <4
• Aesara/Theano Version: aesara 2.7.3
• Python Version: 3.9.12
• Operating system: Windows 10
• How did you install PyMC/PyMC3: conda

[ricardoV94]

Why does this happen? Because the conda list is outdated?

[cluhmann]

Not clear, but this been suggested on discourse at least once (e.g., here).

[twiecki]

Some conda thing that in existing environments it sometimes solves for older versions. i'll do a PR.