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` ranking_dataset_common
`public` pairwise_strength_ranker_common
`public` score_ranker_common
Uses:
avltree
format
list
Remarks:
(none)
Inherited public predicates:
check_option/1 check_options/1 check_ranker/1 default_option/1 default_options/1 diagnostic/2 diagnostics/2 export_to_clauses/4 export_to_file/4 grouped_dataset_groups/2 grouped_dataset_items/2 grouped_dataset_items/3 grouped_dataset_summary/2 learn/2 learn/3 option/2 option/3 pairwise_dataset_connected_components/2 pairwise_dataset_declared_items/2 pairwise_dataset_items/2 pairwise_dataset_matchups/2 pairwise_dataset_preferences/2 pairwise_dataset_summary/2 pairwise_dataset_win_totals/2 pairwise_measurement_dataset_connected_components/2 pairwise_measurement_dataset_declared_items/2 pairwise_measurement_dataset_items/2 pairwise_measurement_dataset_measurements/2 pairwise_measurement_dataset_summary/2 print_ranker/1 rank/3 ranker_options/2 scores/2 temporal_pairwise_dataset_connected_components/2 temporal_pairwise_dataset_declared_items/2 temporal_pairwise_dataset_games/2 temporal_pairwise_dataset_games/3 temporal_pairwise_dataset_items/2 temporal_pairwise_dataset_periods/2 temporal_pairwise_dataset_summary/2 valid_option/1 valid_options/1 valid_ranker/1 validate_grouped_dataset/1 validate_grouped_dataset/2 validate_pairwise_dataset/1 validate_pairwise_dataset/2 validate_pairwise_measurement_dataset/1 validate_pairwise_measurement_dataset/2 validate_temporal_pairwise_dataset/1 validate_temporal_pairwise_dataset/2

## 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)

See also

pairwise_ranking_dataset_protocol, ranking_dataset_protocol, ranker_protocol, regularized_bradley_terry_ranker