.. index:: single: bradley_terry_ranker .. _bradley_terry_ranker/0:

.. rst-class:: right

object

bradley_terry_ranker

Bradley-Terry pairwise preference ranker. Learns one positive strength parameter per item from a dataset object implementing the pairwise_ranking_dataset_protocol protocol when the directed win graph admits a finite Bradley-Terry maximum-likelihood estimate, and returns a self-describing ranker term with diagnostics that can be used for ranking and export.

| Availability: | logtalk_load(bradley_terry_ranker(loader))

| Author: Paulo Moura | Version: 2:0:0 | Date: 2026-05-06

| Compilation flags: | static, context_switching_calls

| Imports: | public :ref:`ranking_dataset_common <ranking_dataset_common/0>` | public :ref:`pairwise_strength_ranker_common <pairwise_strength_ranker_common/0>` | public :ref:`score_ranker_common <score_ranker_common/0>` | Uses: | :ref:`avltree <avltree/0>` | :ref:`format <format/0>` | :ref:`list <list/0>`

| Remarks: | (none)

| Inherited public predicates: |  :ref:`options_protocol/0::check_option/1`  :ref:`options_protocol/0::check_options/1`  :ref:`ranker_protocol/0::check_ranker/1`  :ref:`options_protocol/0::default_option/1`  :ref:`options_protocol/0::default_options/1`  :ref:`ranker_protocol/0::diagnostic/2`  :ref:`ranker_protocol/0::diagnostics/2`  :ref:`ranker_protocol/0::export_to_clauses/4`  :ref:`ranker_protocol/0::export_to_file/4`  :ref:`ranking_dataset_common/0::grouped_dataset_groups/2`  :ref:`ranking_dataset_common/0::grouped_dataset_items/2`  :ref:`ranking_dataset_common/0::grouped_dataset_items/3`  :ref:`ranking_dataset_common/0::grouped_dataset_summary/2`  :ref:`ranker_protocol/0::learn/2`  :ref:`ranker_protocol/0::learn/3`  :ref:`options_protocol/0::option/2`  :ref:`options_protocol/0::option/3`  :ref:`ranking_dataset_common/0::pairwise_dataset_connected_components/2`  :ref:`ranking_dataset_common/0::pairwise_dataset_declared_items/2`  :ref:`ranking_dataset_common/0::pairwise_dataset_items/2`  :ref:`ranking_dataset_common/0::pairwise_dataset_matchups/2`  :ref:`ranking_dataset_common/0::pairwise_dataset_preferences/2`  :ref:`ranking_dataset_common/0::pairwise_dataset_summary/2`  :ref:`ranking_dataset_common/0::pairwise_dataset_win_totals/2`  :ref:`ranking_dataset_common/0::pairwise_measurement_dataset_connected_components/2`  :ref:`ranking_dataset_common/0::pairwise_measurement_dataset_declared_items/2`  :ref:`ranking_dataset_common/0::pairwise_measurement_dataset_items/2`  :ref:`ranking_dataset_common/0::pairwise_measurement_dataset_measurements/2`  :ref:`ranking_dataset_common/0::pairwise_measurement_dataset_summary/2`  :ref:`ranker_protocol/0::print_ranker/1`  :ref:`ranker_protocol/0::rank/3`  :ref:`ranker_protocol/0::ranker_options/2`  :ref:`ranker_protocol/0::scores/2`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_connected_components/2`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_declared_items/2`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_games/2`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_games/3`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_items/2`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_periods/2`  :ref:`ranking_dataset_common/0::temporal_pairwise_dataset_summary/2`  :ref:`options_protocol/0::valid_option/1`  :ref:`options_protocol/0::valid_options/1`  :ref:`ranker_protocol/0::valid_ranker/1`  :ref:`ranking_dataset_common/0::validate_grouped_dataset/1`  :ref:`ranking_dataset_common/0::validate_grouped_dataset/2`  :ref:`ranking_dataset_common/0::validate_pairwise_dataset/1`  :ref:`ranking_dataset_common/0::validate_pairwise_dataset/2`  :ref:`ranking_dataset_common/0::validate_pairwise_measurement_dataset/1`  :ref:`ranking_dataset_common/0::validate_pairwise_measurement_dataset/2`  :ref:`ranking_dataset_common/0::validate_temporal_pairwise_dataset/1`  :ref:`ranking_dataset_common/0::validate_temporal_pairwise_dataset/2`  

.. contents:: :local: :backlinks: top

Public predicates

(no local declarations; see entity ancestors if any)

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)

.. seealso::

:ref:`pairwise_ranking_dataset_protocol <pairwise_ranking_dataset_protocol/0>`, :ref:`ranking_dataset_protocol <ranking_dataset_protocol/0>`, :ref:`ranker_protocol <ranker_protocol/0>`, :ref:`regularized_bradley_terry_ranker <regularized_bradley_terry_ranker/0>`