update examples

docs/guide/examples.rst

@@ -5,10 +5,19 @@ There are several examples to help you see LensKit in action:
 
 * The `Getting Started guide`_
 * The `LensKit demo experiment`_
-* Our `extended Book Gender paper`_ shows LensKit in use in an advanced experiment
 
 .. _Getting Started guide: GettingStarted.html
 .. _LensKit demo experiment: https://github.com/lenskit/lk-demo-experiment
+
+
+Old Examples
+------------
+
+These are examples of using LensKit 0.x in practice.  They have not been updated
+to LensKit 2024.1 and later.
+
+* Michael's `extended Book Gender paper`_ shows LensKit in use in an advanced experiment
+
 .. _extended Book Gender paper: https://md.ekstrandom.net/pubs/bag-extended
 
 In addition, PBS's `Crash Course AI episode on recommender systems`_ demonstrates