PostGIS  2.1.10dev-r@@SVN_REVISION@@
PG_FUNCTION_INFO_V1 ( gserialized_gist_sel  )

This function should return an estimation of the number of rows returned by a query involving an overlap check ( it's the restrict function for the && operator )

It can make use (if available) of the statistics collected by the geometry analyzer function.

Note that the good work is done by estimate_selectivity() above. This function just tries to find the search_box, loads the statistics and invoke the work-horse.