related issue for EHC: issue1196

Todo list:

- https://www.fast-downward.org/latest/documentation/search/ConstraintGenerator/#lm-cut_landmark_constraints
  - remove Pommerening et al. ICAPS 2014
  - remove Bonet IJCAI 2013
  - add LM-CUT paper Helmert & Domshlak ICAPS 2009
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#additive_heuristic
  - bonet-geffner-aij2001
  - keyder-geffner-ecai2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#context-enhanced_additive_heuristic
  - helmert-geffner-icaps2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#causal_graph_heuristic
  - helmert-icaps2004
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#ff_heuristic
  - hoffmann-nebel-jair2001 (the AI lecture references this for the original h^FF)
  - keyder-geffner-ecai2008 (the AI lecture references this for FF / additive heuristic h^FF)
  - fix "computedexactly"
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#hm_heuristic
  - haslum-geffner-aips2000
  - the implementation is very inefficient, though
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#max_heuristic
  - bonet-geffner-aij2001
  - keyder-geffner-ecai2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#landmark_cost_partitioning_heuristic
  - for original heuristic: https://jair.org/index.php/jair/article/view/10667
  - cost partitioning: karpas-domshlak-ijcai2009
  - landmark progression: buechner-et-al-icaps2023 (already cited there)
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#landmark_sum_heuristic
  - add as first reference for original heuristic: https://jair.org/index.php/jair/article/view/10667
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#landmark-cut_heuristic
  - helmert-domshlak-icaps2009
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#merge-and-shrink_heuristic
  - remove first reference (sievers-et-al-aaai2014), reformulate next sentence
  - move sievers-et-al-icaps2016 to somewhere else (probably to MergeStrategy)
  - replace JACM 2014 with JAIR 2021
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#preference_evaluator
  - richter-helmert-icaps2009
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#canonical_pdb
  - idea comes from: haslum-et-al-aaai2007
  - discussed in context with other cost-partitioning methods: seipp-et-al-icaps2017
  - implementation details: sievers-et-al-socs2017 (add as for iPDBs)
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#zero-one_pdb
  - idea from: haslum-et-al-aaai2005
  - greedy zero-one cost partitioning: edelkamp-aips2002
  - discussed in context with other cost-partitioning methods: seipp-et-al-icaps2017
  - implementation details: sievers-et-al-socs2017 (add as for iPDBs)
- https://www.fast-downward.org/latest/documentation/search/LabelReduction/#exact_generalized_label_reduction
  - sievers-helmert-jair2021
- https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#exhaustive_landmarks
  - We should say something like "Tests for every atom if the relaxed planning
    task where all achievers of this atom are removed is solvable. If yes, it
    is a landmark. For the concept of delete relaxation, see:"
  - hoffmann-nebel-jair2001 (the FF paper)
- https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#hm_landmarks
  - paper is mentioned, add full reference (keyder-et-al-ecai2010)
  - https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#rhw_landmarks
  - comes from the paper already mentioned (richter-et-al-aaai2008)
  - add LAMA paper richter-westphal-jair2010 (This is where the algorithm is described in more detail.)
- https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#zhugivan_landmarks
  - paper is mentioned, add full reference (zhu-givan-icaps2003dc)
- https://www.fast-downward.org/latest/documentation/search/MergeScoringFunction/#dfp_scoring
  - replace draeger-et-al-spin2006 by draeger-et-al-sttt2009
- https://www.fast-downward.org/latest/documentation/search/MergeScoringFunction/#miasm
  - MIASM idea comes from: fan-et-al-socs2014
  - dynMIASM: sievers-et-al-icaps2016 (already there)
- https://www.fast-downward.org/latest/documentation/search/MergeScoringFunction/#single_random
  - sievers-et-al-icaps2016
- https://www.fast-downward.org/latest/documentation/search/MergeTree/#linear_merge_trees
  - cg_goal_level, goal_cg_level: helmert-et-al-aaai2007 (already there)
  - level: sievers-et-al-icaps2016
  - reverse_level: nissim-et-al-ijcai2011
  - no reference for cg_goal_random, random
- https://www.fast-downward.org/latest/documentation/search/OpenList/#alternation_open_list
  - idea from: helmert-jair2006
  - details: roeger-helmert-icaps2010
- https://www.fast-downward.org/latest/documentation/search/OpenList/#pareto_open_list
  - roeger-helmert-icaps2010
- https://www.fast-downward.org/latest/documentation/search/OpenList/#tie-breaking_open_list
  - roeger-helmert-icaps2010
- https://www.fast-downward.org/HEAD/documentation/search/PatternGenerator/#random_pattern
  - fix "of the the paper"
- https://www.fast-downward.org/latest/documentation/search/PruningMethod/#limited_pruning
  - alkhazraji-et-al-ipc2014
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#lazy_enforced_hill-climbing
  - enforced hillclimbing: hoffmann-nebel-jair2001
    - but this is *not* what is implemented
    - see summary of https://issues.fast-downward.org/issue1196
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#iterated_search
  - richter-westphal-jair2010
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#lazy_best-first_search
  - helmert-jair2006
  - richter-helmert-icaps2009
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#greedy_search_lazy
  - helmert-jair2006
  - richter-helmert-icaps2009
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#weighted_a_search_lazy
  - lazy aspect:
    - helmert-jair2006
    - richter-helmert-icaps2009
  - weighted: richter-westphal-jair2010
- https://www.fast-downward.org/HEAD/documentation/search/SubtaskGenerator/#abstraction_by_goals
  - seipp-helmert-icaps2014
  - seipp-helmert-jair2018
- https://www.fast-downward.org/HEAD/documentation/search/SubtaskGenerator/#abstraction_by_landmarks
  - seipp-helmert-icaps2014
  - seipp-helmert-jair2018
- https://www.fast-downward.org/HEAD/documentation/search/SubtaskGenerator/#no_abstraction
  - seipp-helmert-icaps2014
  - seipp-helmert-jair2018

Done list:

- https://www.fast-downward.org/latest/documentation/search/AbstractTask/#cost-adapted_task
  - LAMA paper https://jair.org/index.php/jair/article/view/10667

In a FastDownward meeting we discussed issue1215 and said the outdated URLs for the component documentation should be part of this issue issue1200.
If possible they should not link to aaai but should refer to something more reliable like the DOI.

We often put TODO lists in the summary, perhaps you want to do this?

If they also appear struck through there, perhaps we can then find out why and fix it.

For some reason all items of the todo-list in msg11996 are struck through which makes it look like everything is done. Together with the merged PR this caused some confusion whether this issue should be closed.

The merged PR added only a single reference (to cost adapted task). Thus, everything else from the todo-list is still open and this issue should not yet be closed.

Esther and I looked at the PR and merged it.

A reference for cost adapted task can be reviewed: https://github.com/aibasel/downward/pull/282

Since it does not look like someone will further work on this very soon, I archive our shared notes from the sprint here (repeating the todo-list now that the line break issues of the tracker are fixed):


Example of how a reference will look like when added to the code of a search plugin: https://www.fast-downward.org/latest/documentation/search/ConstraintGenerator/

TODO: We need to check all existing links. Ideally use DOIs

The "axioms={approximate_negative,approximate_negative_cycles}" options are used in many evaluators (add, cea, cg, ff, hmax; also landmark_sum, but see below). What it does is *not* described in the literature, and for all these heuristics how we deal with axioms or conditional effects is *not* described in the "regular" papers we cite for these heuristics. Instead, how we deal with conditional effects is described in the Fast Downward journal paper (Helmert, JAIR 2006), and how we deal with axioms with default parameters is also described there *for the case where there are no negative cycles in axioms*. The paper only discusses cg and ff, but what it says for cg also applies to cea, and what it says for ff also applies to add and hmax.

For landmark_sum, it's not so clear to me (Malte) what the axioms option affects, requires a closer look.


List of gathered references (the todo-list)

- https://www.fast-downward.org/latest/documentation/search/AbstractTask/#cost-adapted_task
  - LAMA paper https://jair.org/index.php/jair/article/view/10667~~
- https://www.fast-downward.org/latest/documentation/search/ConstraintGenerator/#lm-cut_landmark_constraints
  - remove Pommerening et al. ICAPS 2014
  - remove Bonet IJCAI 2013
  - add LM-CUT paper Helmert & Domshlak ICAPS 2009
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#additive_heuristic
  - bonet-geffner-aij2001
  - keyder-geffner-ecai2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#context-enhanced_additive_heuristic
  - helmert-geffner-icaps2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#causal_graph_heuristic
  - helmert-icaps2004
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#ff_heuristic
  - hoffmann-nebel-jair2001 (the AI lecture references this for the original h^FF)
  - keyder-geffner-ecai2008 (the AI lecture references this for FF / additive heuristic h^FF)
  - fix "computedexactly"
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#hm_heuristic
  - haslum-geffner-aips2000
  - the implementation is very inefficient, though
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#max_heuristic
  - bonet-geffner-aij2001
  - keyder-geffner-ecai2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#landmark_cost_partitioning_heuristic
  - for original heuristic: https://jair.org/index.php/jair/article/view/10667
  - cost partitioning: karpas-domshlak-ijcai2009
  - landmark progression: buechner-et-al-icaps2023 (already cited there)
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#landmark_sum_heuristic
  - add as first reference for original heuristic: https://jair.org/index.php/jair/article/view/10667
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#landmark-cut_heuristic
  - helmert-domshlak-icaps2009
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#merge-and-shrink_heuristic
  - remove first reference (sievers-et-al-aaai2014), reformulate next sentence
  - move sievers-et-al-icaps2016 to somewhere else (probably to MergeStrategy)
  - replace JACM 2014 with JAIR 2021
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#preference_evaluator
  - richter-helmert-icaps2009
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#canonical_pdb
  - idea comes from: haslum-et-al-aaai2007
  - discussed in context with other cost-partitioning methods: seipp-et-al-icaps2017
  - implementation details: sievers-et-al-socs2017 (add as for iPDBs)
- https://www.fast-downward.org/latest/documentation/search/Evaluator/#zero-one_pdb
  - idea from: haslum-et-al-aaai2005
  - greedy zero-one cost partitioning: edelkamp-aips2002
  - discussed in context with other cost-partitioning methods: seipp-et-al-icaps2017
  - implementation details: sievers-et-al-socs2017 (add as for iPDBs)
- https://www.fast-downward.org/latest/documentation/search/LabelReduction/#exact_generalized_label_reduction
  - sievers-helmert-jair2021
- https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#exhaustive_landmarks
  - We should say something like "Tests for every atom if the relaxed planning
    task where all achievers of this atom are removed is solvable. If yes, it
    is a landmark. For the concept of delete relaxation, see:"
  - hoffmann-nebel-jair2001 (the FF paper)
- https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#hm_landmarks
  - paper is mentioned, add full reference (keyder-et-al-ecai2010)
  - https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#rhw_landmarks
  - comes from the paper already mentioned (richter-et-al-aaai2008)
  - add LAMA paper richter-westphal-jair2010 (This is where the algorithm is described in more detail.)
- https://www.fast-downward.org/latest/documentation/search/LandmarkFactory/#zhugivan_landmarks
  - paper is mentioned, add full reference (zhu-givan-icaps2003dc)
- https://www.fast-downward.org/latest/documentation/search/MergeScoringFunction/#dfp_scoring
  - replace draeger-et-al-spin2006 by draeger-et-al-sttt2009
- https://www.fast-downward.org/latest/documentation/search/MergeScoringFunction/#miasm
  - MIASM idea comes from: fan-et-al-socs2014
  - dynMIASM: sievers-et-al-icaps2016 (already there)
- https://www.fast-downward.org/latest/documentation/search/MergeScoringFunction/#single_random
  - sievers-et-al-icaps2016
- https://www.fast-downward.org/latest/documentation/search/MergeTree/#linear_merge_trees
  - cg_goal_level, goal_cg_level: helmert-et-al-aaai2007 (already there)
  - level: sievers-et-al-icaps2016
  - reverse_level: nissim-et-al-ijcai2011
  - no reference for cg_goal_random, random
- https://www.fast-downward.org/latest/documentation/search/OpenList/#alternation_open_list
  - idea from: helmert-jair2006
  - details: roeger-helmert-icaps2010
- https://www.fast-downward.org/latest/documentation/search/OpenList/#pareto_open_list
  - roeger-helmert-icaps2010
- https://www.fast-downward.org/latest/documentation/search/OpenList/#tie-breaking_open_list
  - roeger-helmert-icaps2010
- https://www.fast-downward.org/HEAD/documentation/search/PatternGenerator/#random_pattern
  - fix "of the the paper"
- https://www.fast-downward.org/latest/documentation/search/PruningMethod/#limited_pruning
  - alkhazraji-et-al-ipc2014
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#lazy_enforced_hill-climbing
  - enforced hillclimbing: hoffmann-nebel-jair2001
    - but this is *not* what is implemented
    - see summary of https://issues.fast-downward.org/issue1196
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#iterated_search
  - richter-westphal-jair2010
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#lazy_best-first_search
  - helmert-jair2006
  - richter-helmert-icaps2009
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#greedy_search_lazy
  - helmert-jair2006
  - richter-helmert-icaps2009
- https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#weighted_a_search_lazy
  - lazy aspect:
    - helmert-jair2006
    - richter-helmert-icaps2009
  - weighted: richter-westphal-jair2010
- https://www.fast-downward.org/HEAD/documentation/search/SubtaskGenerator/#abstraction_by_goals
  - seipp-helmert-icaps2014
  - seipp-helmert-jair2018
- https://www.fast-downward.org/HEAD/documentation/search/SubtaskGenerator/#abstraction_by_landmarks
  - seipp-helmert-icaps2014
  - seipp-helmert-jair2018
- https://www.fast-downward.org/HEAD/documentation/search/SubtaskGenerator/#no_abstraction
  - seipp-helmert-icaps2014
  - seipp-helmert-jair2018

Many components are related to one or multiple papers that one might want to
cite when using Fast Downward configurations based on them. For some components
(e.g. pho_constraints) such references are included in the documentation but for
many they are missing. During the current sprint we wanted to improve this and
so far gathered the following list that next needs to be implemented in the
actual documentation.

- https://www.fast-downward.org/latest/documentation/
search/AbstractTask/#cost-adapted_task
  - LAMA paper https://jair.org/
index.php/jair/article/view/10667
- https://www.fast-downward.org/latest/
documentation/search/ConstraintGenerator/#lm-cut_landmark_constraints
  - remove
Pommerening et al. ICAPS 2014
  - remove Bonet IJCAI 2013
  - add LM-CUT paper
Helmert & Domshlak ICAPS 2009
- https://www.fast-downward.org/latest/
documentation/search/Evaluator/#additive_heuristic
  - bonet-geffner-aij2001
  -
keyder-geffner-ecai2008
- https://www.fast-downward.org/latest/documentation/
search/Evaluator/#context-enhanced_additive_heuristic
  - helmert-geffner-
icaps2008
- https://www.fast-downward.org/latest/documentation/search/Evaluator/
#causal_graph_heuristic
  - helmert-icaps2004
- https://www.fast-downward.org/
latest/documentation/search/Evaluator/#ff_heuristic
  - hoffmann-nebel-jair2001
(the AI lecture references this for the original h^FF)
  - keyder-geffner-
ecai2008 (the AI lecture references this for FF / additive heuristic h^FF)
  -
fix "computedexactly"
- https://www.fast-downward.org/latest/documentation/
search/Evaluator/#hm_heuristic
  - haslum-geffner-aips2000
  - the
implementation is very inefficient, though
- https://www.fast-downward.org/
latest/documentation/search/Evaluator/#max_heuristic
  - bonet-geffner-aij2001
 - keyder-geffner-ecai2008
- https://www.fast-downward.org/latest/documentation/
search/Evaluator/#landmark_cost_partitioning_heuristic
  - for original
heuristic: https://jair.org/index.php/jair/article/view/10667
  - cost
partitioning: karpas-domshlak-ijcai2009
  - landmark progression: buechner-et-
al-icaps2023 (already cited there)
- https://www.fast-downward.org/latest/
documentation/search/Evaluator/#landmark_sum_heuristic
  - add as first
reference for original heuristic: https://jair.org/index.php/jair/article/
view/10667
- https://www.fast-downward.org/latest/documentation/search/
Evaluator/#landmark-cut_heuristic
  - helmert-domshlak-icaps2009
- https://
www.fast-downward.org/latest/documentation/search/Evaluator/#merge-and-
shrink_heuristic
  - remove first reference (sievers-et-al-aaai2014),
reformulate next sentence
  - TODO move sievers-et-al-icaps2016 to somewhere
else (probably to MergeStrategy)
  - replace JACM 2014 with JAIR 2021
- https://
www.fast-downward.org/latest/documentation/search/Evaluator/
#preference_evaluator
  - richter-helmert-icaps2009
- https://www.fast-
downward.org/latest/documentation/search/Evaluator/#canonical_pdb
  - idea comes
from: haslum-et-al-aaai2007
  - discussed in context with other cost-
partitioning methods: seipp-et-al-icaps2017
  - implementation details: sievers-
et-al-socs2017 (add as for iPDBs)
- https://www.fast-downward.org/latest/
documentation/search/Evaluator/#zero-one_pdb
  - idea from: haslum-et-al-
aaai2005
  - greedy zero-one cost partitioning: edelkamp-aips2002
  - discussed
in context with other cost-partitioning methods: seipp-et-al-icaps2017
  -
implementation details: sievers-et-al-socs2017 (add as for iPDBs)
- https://
www.fast-downward.org/latest/documentation/search/LabelReduction/
#exact_generalized_label_reduction
  - sievers-helmert-jair2021
- https://
www.fast-downward.org/latest/documentation/search/LandmarkFactory/
#exhaustive_landmarks
  - We should say something like "Tests for every atom if
the relaxed planning task where all achievers of this atom are removed is
solvable. If yes, it is a landmark. For the concept of delete relaxation, see:"
 - hoffmann-nebel-jair2001 (the FF paper)
- https://www.fast-downward.org/
latest/documentation/search/LandmarkFactory/#hm_landmarks
  - paper is
mentioned, add full reference (keyder-et-al-ecai2010)
- https://www.fast-
downward.org/latest/documentation/search/LandmarkFactory/#rhw_landmarks
  -
comes from the paper already mentioned (richter-et-al-aaai2008)
  - add LAMA
paper richter-westphal-jair2010 (This is where the algorithm is described in
more detail.)
- https://www.fast-downward.org/latest/documentation/search/
LandmarkFactory/#zhugivan_landmarks
  - paper is mentioned, add full reference
(zhu-givan-icaps2003dc)
- https://www.fast-downward.org/latest/documentation/
search/MergeScoringFunction/#dfp_scoring
  - replace draeger-et-al-spin2006 by
draeger-et-al-sttt2009
- https://www.fast-downward.org/latest/documentation/
search/MergeScoringFunction/#miasm
  - MIASM idea comes from: fan-et-al-
socs2014
  - dynMIASM: sievers-et-al-icaps2016 (already there)
- https://
www.fast-downward.org/latest/documentation/search/MergeScoringFunction/
#single_random
  - sievers-et-al-icaps2016
- https://www.fast-downward.org/
latest/documentation/search/MergeTree/#linear_merge_trees
  - cg_goal_level,
goal_cg_level: helmert-et-al-aaai2007 (already there)
  - level: sievers-et-al-
icaps2016
  - reverse_level: nissim-et-al-ijcai2011
  - no reference for
cg_goal_random, random
- https://www.fast-downward.org/latest/documentation/
search/OpenList/#alternation_open_list
  - idea from: helmert-jair2006
  -
details: roeger-helmert-icaps2010
- https://www.fast-downward.org/latest/
documentation/search/OpenList/#pareto_open_list
  - roeger-helmert-icaps2010
-
https://www.fast-downward.org/latest/documentation/search/OpenList/#tie-
breaking_open_list
  - roeger-helmert-icaps2010
- https://www.fast-downward.org/
HEAD/documentation/search/PatternGenerator/#random_pattern
  - fix "of the the
paper"
- https://www.fast-downward.org/latest/documentation/search/
PruningMethod/#limited_pruning
  - alkhazraji-et-al-ipc2014
- https://www.fast-
downward.org/latest/documentation/search/SearchAlgorithm/#lazy_enforced_hill-
climbing
  - enforced hillclimbing: hoffmann-nebel-jair2001
    - but this is
*not* what is implemented
    - see summary of https://issues.fast-downward.org/
issue1196
- https://www.fast-downward.org/latest/documentation/search/
SearchAlgorithm/#iterated_search
  - richter-westphal-jair2010
- https://
www.fast-downward.org/latest/documentation/search/SearchAlgorithm/#lazy_best-
first_search
  - helmert-jair2006
  - richter-helmert-icaps2009
- https://
www.fast-downward.org/latest/documentation/search/SearchAlgorithm/
#greedy_search_lazy
  - helmert-jair2006
  - richter-helmert-icaps2009
-
https://www.fast-downward.org/latest/documentation/search/SearchAlgorithm/
#weighted_a_search_lazy
  - lazy aspect:
    - helmert-jair2006
    - richter-
helmert-icaps2009
  - weighted: richter-westphal-jair2010
- https://www.fast-
downward.org/HEAD/documentation/search/SubtaskGenerator/#abstraction_by_goals
 - seipp-helmert-icaps2014
  - seipp-helmert-jair2018
- https://www.fast-
downward.org/HEAD/documentation/search/SubtaskGenerator/
#abstraction_by_landmarks
  - seipp-helmert-icaps2014
  - seipp-helmert-
jair2018
- https://www.fast-downward.org/HEAD/documentation/search/
SubtaskGenerator/#no_abstraction
  - seipp-helmert-icaps2014
  - seipp-helmert-
jair2018