DOC: the two notebook examples for Linear Mixed Models have been deleted

[jeanbaptisteb]

Describe the bug

The following documentation page https://github.com/statsmodels/statsmodels/wiki/Examples#linear-mixed-models mentions two notebooks as examples for using Linear Mixed Models in statsmodels:

• Two examples using both R (LME4) and Statsmodels [HTML View] (http://nbviewer.ipython.org/urls/umich.box.com/shared/static/6tfc1e0q6jincsv5pgfa.ipynb)
• Regression analysis of healthcare spending in Vietnam, using mixed models and GEE. Stata results provided for comparison. [HTML View] (http://nbviewer.ipython.org/urls/umich.box.com/shared/static/lc6uf6dmabmitjbup3yt.ipynb)

However, the two links point to 403 error pages. I tested it in Firefox and Chrome. Here's a screenshot of one of these error messages:

After investigating a bit, and following the URLs wrapped in these nbviewer.org links, it seems that the notebooks have simply been deleted, see https://umich.app.box.com/public/static/lc6uf6dmabmitjbup3yt.ipynb and https://umich.app.box.com/public/static/6tfc1e0q6jincsv5pgfa.ipynb.

Expected Solution

Either updating the links if they have been moved to somewhere else (I don't know if it's the case), or making the links available again, or simply deleting this section of the documentation.

Thanks,

[josef-pkt]

They are currently on dropbox https://www.dropbox.com/scl/fo/mylhfjbpl2zlc5z5m4prq/h?dl=0&rlkey=li52chs6rcl6lejspde6n0oqf search for "lme" and "mixed" in notebook names to find the notebooks on the page.