category

plackett_luce_common

Shared helpers for grouped Plackett-Luce rankers.

Availability:
logtalk_load(ranking_protocols(loader))
Author: Paulo Moura
Version: 1:0:0
Date: 2026-04-26
Compilation flags:
static
Uses:
avltree
list
Remarks:
(none)
Inherited public predicates:
(none)

Public predicates

(no local declarations; see entity ancestors if any)

Protected predicates

index_items/3

Builds Item-Index pairs for the ordered training items.

Compilation flags:
static
Template:
index_items(Items,Index,Indices)
Mode and number of proofs:
index_items(+list,+integer,-list) - one

preprocess_groups/10

Builds per-group choice steps, selection counts, and forward and reverse adjacency dictionaries from grouped rankings under the selected traversal order.

Compilation flags:
static
Template:
preprocess_groups(Order,Groups,Dataset,MissingRelevance,IndexDictionary,Count,Steps,SelectionCounts,DirectedAdjacency,ReverseAdjacency)
Mode and number of proofs:
preprocess_groups(+atom,+list,+object_identifier,+atom,+compound,+integer,-list,-list,-compound,-compound) - one

selection_exposures/4

Computes the per-item exposure counts implied by the grouped choice steps and the current value dictionary.

Compilation flags:
static
Template:
selection_exposures(Steps,SelectionCounts,ValueDictionary,ExposureCounts)
Mode and number of proofs:
selection_exposures(+list,+list,+compound,-list) - one

normalize_strengths/6

Normalizes raw strength values to sum to one while tracking the maximum absolute change from the current strengths.

Compilation flags:
static
Template:
normalize_strengths(RawStrengths,TotalRawStrength,CurrentStrengths,Strengths,MaximumDifference0,MaximumDifference)
Mode and number of proofs:
normalize_strengths(+list(number),+number,+list(number),-list(number),+number,-number) - one

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)