Repository: statsmodels/statsmodels

Issue:
Broken links in documentation
#### Describe the bug

The documentation contains several broken links to external sites that do not exists anymore.

#### Code Sample, a copy-pastable example if possible

Run the following command from the `docs/` folder:
```bash
sphinx-build -b linkcheck source/ build/linkcheck/ -D linkcheck_ignore="https://github.com/statsmodels/statsmodels/.*" -j auto
```
Results will be written to `docs/build/linkcheck/output.txt` and lists the following broken links:
```
dev/index.rst:41: [broken] https://github.com/numpy/numpy/blob/master/doc/HOWTO_DOCUMENT.rst.txt#docstring-standard: Anchor 'docstring-standard' not found
generated/statsmodels.duration.survfunc.SurvfuncRight.quantile_ci.rst:43: [broken] http://support.sas.com/documentation/cdl/en/statug/68162/HTML/default/viewer.htm#statug_lifetest_details03.htm: Anchor 'statug_lifetest_details03.htm' not found
generated/statsmodels.genmod.bayes_mixed_glm.BinomialBayesMixedGLM.rst:97: [broken] https://support.sas.com/documentation/cdl/en/statug/63033/HTML/default/viewer.htm#statug_intromix_a0000000215.htm: Anchor 'statug_intromix_a0000000215.htm' not found
generated/statsmodels.genmod.bayes_mixed_glm.BinomialBayesMixedGLM.rst:100: [broken] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866838/: 403 Client Error: Forbidden for url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866838/
generated/statsmodels.genmod.bayes_mixed_glm.PoissonBayesMixedGLM.rst:97: [broken] https://support.sas.com/documentation/cdl/en/statug/63033/HTML/default/viewer.htm#statug_intromix_a0000000215.htm: Anchor 'statug_intromix_a0000000215.htm' not found
generated/statsmodels.genmod.bayes_mixed_glm.PoissonBayesMixedGLM.rst:100: [broken] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866838/: 403 Client Error: Forbidden for url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866838/
generated/statsmodels.genmod.cov_struct.GlobalOddsRatio.rst:33: [broken] http://www.jstor.org/stable/2533173: 403 Client Error: Forbidden for url: https://www.jstor.org/stable/2533173
generated/statsmodels.genmod.families.family.Tweedie.loglike_obs.rst:41: [broken] https://www.jstor.org/stable/2336136: 403 Client Error: Forbidden for url: https://www.jstor.org/stable/2336136
generated/statsmodels.nonparametric.kernel_density.EstimatorSettings.rst:42: [broken] https://pythonhosted.org/joblib/parallel.html: 404 Client Error: Not Found for url: https://pythonhosted.org/joblib/parallel.html
generated/statsmodels.stats.contingency_tables.Table.rst:39: [broken] https://onlinecourses.science.psu.edu/stat504/node/86: HTTPSConnectionPool(host='onlinecourses.science.psu.edu', port=443): Max retries exceeded with url: /stat504/node/86 (Caused by SSLError(SSLError("bad handshake: Error([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')])")))
generated/statsmodels.stats.weightstats.DescrStatsW.quantile.rst:50: [broken] https://support.sas.com/documentation/cdl/en/procstat/63104/HTML/default/viewer.htm#procstat_univariate_sect028.htm: Anchor 'procstat_univariate_sect028.htm' not found
imputation.rst:58: [broken] https://pandas.pydata.org/pandas-docs/stable/missing_data.html#working-with-missing-data: Anchor 'working-with-missing-data' not found
install.rst:22: [broken] https://www.continuum.io/downloads: 404 Client Error: Not Found for url: https://www.continuum.io/downloads
install.rst:163: [broken] http://pythonhosted.org/joblib/: 404 Client Error: Not Found for url: https://pythonhosted.org/joblib/
mixed_linear.rst:169: [broken] http://lme4.r-forge.r-project.org/lMMwR/lrgprt.pdf: 404 Client Error: Not Found for url: http://lme4.r-forge.r-project.org/lMMwR/lrgprt.pdf
release/version0.5.rst:108: [broken] https://www.statsmodels.org/devel/examples/index.html#notebook-examples: Anchor 'notebook-examples' not found
sandbox.rst:42: [broken] https://pandas.pydata.org/pandas-docs/stable/computation.html#moving-rolling-statistics-moments: Anchor 'moving-rolling-statistics-moments' not found
```

#### Expected Output

There should be no broken links.

#### Output of ``import statsmodels.api as sm; sm.show_versions()``

<details>
INSTALLED VERSIONS
------------------
Python: 3.8.3.final.0
OS: Linux 5.6.11-200.fc31.x86_64 #1 SMP Wed May 6 19:10:55 UTC 2020 x86_64
byteorder: little
LC_ALL: None
LANG: de_DE.UTF-8

statsmodels
===========

Installed: v0.12.0.dev0+313.g0551e89f7 (/home/sebp/Projekte/statsmodels/statsmodels)

Required Dependencies
=====================

cython: 0.29.17 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/Cython)
numpy: 1.18.1 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/numpy)
scipy: 1.4.1 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/scipy)
pandas: 1.0.3 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/pandas)
    dateutil: 2.8.1 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/dateutil)
patsy: 0.5.1 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/patsy)

Optional Dependencies
=====================

matplotlib: 3.1.3 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/matplotlib)
    backend: Qt5Agg 
cvxopt: Not installed
joblib: Not installed

Developer Tools
================

IPython: 7.13.0 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/IPython)
    jinja2: 2.11.2 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/jinja2)
sphinx: 3.0.3 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/sphinx)
    pygments: 2.6.1 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/pygments)
pytest: 5.4.2 (/home/sebp/miniconda3/envs/sm/lib/python3.8/site-packages/pytest)
virtualenv: Not installed

</details>



Discussion:

Resolving patch:
diff --git a/statsmodels/nonparametric/_kernel_base.py b/statsmodels/nonparametric/_kernel_base.py
--- a/statsmodels/nonparametric/_kernel_base.py
+++ b/statsmodels/nonparametric/_kernel_base.py
@@ -375,7 +375,7 @@ class EstimatorSettings(object):
         ``joblib.Parallel``.  Default is -1, meaning ``n_cores - 1``, with
         ``n_cores`` the number of available CPU cores.
         See the `joblib documentation
-        <https://pythonhosted.org/joblib/parallel.html>`_ for more details.
+        <https://joblib.readthedocs.io/en/latest/generated/joblib.Parallel.html>`_ for more details.
 
     Examples
     --------


Test patch: