lenskit.metrics.ranking.ListGini
================================

.. py:class:: lenskit.metrics.ranking.ListGini(n = None, *, k = None, items)
   :canonical: lenskit.metrics.ranking._gini.ListGini

   Bases: :py:obj:`GiniBase`


   Measure item diversity of recommendations with the Gini coefficient.

   This computes the Gini coefficient of the *number of lists* that each item
   appears in.

   :param n: The maximum recommendation list length.
   :param items: The item vocabulary or a dataset from which to extract the items.

   :Stability: Caller


   .. py:method:: measure_list(output, test)

      Compute measurements for a single list.

      :returns:

                - A float for simple metrics
                - Intermediate data for decomposed metrics
                - A dict mapping metric names to values for multi-metric classes