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commit 83f4b5de7712cd02ee4f53979d071bddb2b9769f
parent a963b6c4fba9522a4b8e48cb18a7bacb212845bc
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Fri, 21 Feb 2025 11:35:27 +0100

commit with codex

Diffstat:
automata_complementation | 2++
automata_evaluation | 12++++++++++++
automata_weighted | 2++
certain_answers | 4+++-
downwards_closure_cfl_state_complexity | 9+++++++++
downwards_closure_state_complexity | 11+++++++++++
final_weight | 9+++++++++
inconsistency | 5+++++
inconsistency_quantitative | 13+++++++++++++
initial_weight | 9+++++++++
lower_bounds | 3++-
network_reliability | 1+
possible_answers | 9+++++++++
pqe_ucq | 11+++++++++++
probabilistic_database_model | 6++++--
probabilistic_database_neighboring_fields | 10++++++++++
probabilistic_databases | 30++++++++++++++++++++++++++++++
quantitative | 5+++++
representation_system | 11+++++++++++
semiring_idempotent | 7++-----
sjfcq | 2+-
state_complexity | 13+++++++++++++
tdta | 21+++++++++++++++++++++
tree_automaton | 4+---
tree_automaton_bottom_up | 8++++++--
tree_automaton_top_down | 12++++++++++++
uncertain_data | 4++++
27 files changed, 218 insertions(+), 15 deletions(-)

diff --git a/automata_complementation b/automata_complementation @@ -5,3 +5,5 @@ - hard also for [word_automaton_unambiguous] Up: [complementation], [automata] + +Aliases: automaton complement, automaton complementation diff --git a/automata_evaluation b/automata_evaluation @@ -0,0 +1,12 @@ +# Automata evaluation + +Given an [automaton] A and a [word] w, determine if A accepts w + +- for [DFAs]: can be done in O(|w|), simply by following [transitions] +- for [NFAs]: can be done in O(|w| |A|) by [state_set_simulation] + - [conditional_lower_bound] in [backurs2016which] + - reduction from [OV_conjecture] + +- [automata_evaluation_practice] + +Up: [automata_problems] diff --git a/automata_weighted b/automata_weighted @@ -12,6 +12,8 @@ given a [word]: - [sum] over possible [run]s - [product] over [transitions] and [final_states] used +Can be seen as multiplying [matrices] (one [matrix] for each letter), with a [vector] of [initial_weights] and [final_weights] + Schützenberger, 1961 - [automata_weighted_conjugacy] diff --git a/certain_answers b/certain_answers @@ -1,9 +1,11 @@ # Certain answers -Given a [query] Q and [uncertain_data] D, a *certain answer* is a [query_answer] which is true on every [possible_world] of D. If Q is a [Boolean_query], we talk about the query being certain +Given a [query] Q and [uncertain_data] D, a *certain answer* is a [query_answer] which is true on every [possible_world] of D. If Q is a [Boolean_query], we talk about the query being *certain* - [gheerbrant2023querying] Up: [uncertain_data] Aliases: certain answer + +See also: [possible_answers] diff --git a/downwards_closure_cfl_state_complexity b/downwards_closure_cfl_state_complexity @@ -0,0 +1,9 @@ +# Downwards closure CFL state complexity + +We can construct [automata] recognizing the downwards closure of a [CFL]: cf [bachmeier2014finite]. +- As an [NFA], it can be done with an [exponential] set of [states], and there is also an [exponential] [lower_bound]. +- As a [DFA], it can be done with a [doubly_exponential] set of [states], and there is also a [doubly_exponential] [lower_bound] + +Up: [downwards_closure_state_complexity], [CFL] + +See also: [upwards_closure_cfl_state_complexity] diff --git a/downwards_closure_state_complexity b/downwards_closure_state_complexity @@ -0,0 +1,11 @@ +# Downwards closure state complexity + +- [karandikar2014state]: transforming a [DFA] to a [DFA] for the set of [subwords] has [exponential] [lower_bound] (not trivial) + - [lower_bound] on larger alphabet already in [okhotin2010state] +- [downwards_closure_cfl_state_complexity] + +Up: [downwards_closure], [state_complexity] + +Aliases: downward closure state complexity + +See also: [upwards_closure_state_complexity] diff --git a/final_weight b/final_weight @@ -0,0 +1,9 @@ +# Final weight + +The [weight] in a [weighted_automaton] given to each [state] when ending a [run] at this state; in a non-weighted [automaton], the [final_states] would have weight 1 and the [nonfinal_states] would have weight 0 + +Can be represented as a [vector] of weights + +Up: [automata_weighted] + +Aliases: final weights diff --git a/inconsistency b/inconsistency @@ -0,0 +1,5 @@ +# Inconsistency + +- [inconsistency_quantitative] + +Up: [uncertain_data] diff --git a/inconsistency_quantitative b/inconsistency_quantitative @@ -0,0 +1,13 @@ +# Inconsistency quantitative + +[Quantitative] measures of inconsistency ([constraint_violations]): + +- number of minimal inconsistent subsets +- number of tuples that participate to a violation +- minimal number of tuples to remove to satisfy the constraints + - see [database_repairs] and [subset_repairs] +- number of maximal consistent subsets + +Up: [inconsistency] + +See also: [database_repairs] diff --git a/initial_weight b/initial_weight @@ -0,0 +1,9 @@ +# Initial weight + +The [weight] in a [weighted_automaton] given to each [state] when beginning a [run] at this state; in a non-weighted [automaton], the [initial_states] would have weight 1 and the others would have weight 0 + +Can be represented as a [vector] of weights + +Up: [automata_weighted] + +Aliases: initial weights diff --git a/lower_bounds b/lower_bounds @@ -1,6 +1,7 @@ # Lower bounds -[complexity_lower_bounds] +- [complexity_lower_bounds] +- [conditional_lower_bound] Up: [computational_complexity] diff --git a/network_reliability b/network_reliability @@ -2,6 +2,7 @@ - [st_reliability] - [network_reliability_fpras] +- [all_terminal_network_reliability] Up: [graph] diff --git a/possible_answers b/possible_answers @@ -0,0 +1,9 @@ +# Possible answers + +Given a [query] Q and [uncertain_data] D, a *possible answer* is a [query_answer] which is true on some [possible_world] of D. + +See also: [certain_answers] + +Up: [uncertain_data] + +Aliases: possible answer diff --git a/pqe_ucq b/pqe_ucq @@ -0,0 +1,11 @@ +# PQE for UCQ + +- [dichotomy]: [dalvi2012dichotomy] +- new presentation: [kenig2020dichotomy] + +The complexity in the [query] of the [meta_dichotomy] criterion is open + - cf [amarilli2020dichotomy] which says so explicitly + +Up: [pqe] for [union_of_conjunctive_queries] + +See also: [pqe_unsafe] diff --git a/probabilistic_database_model b/probabilistic_database_model @@ -1,8 +1,10 @@ # Probabilistic database model -- [tuple_independent_database] -- [block_independent_disjoint] [database] +- [tuple_independent_database] (TID) +- [block_independent_disjoint] [database] (BID) - [pc_table] - also: [probabilistic_xml] +Relevant source: "Uncertain Data Models", [Encyclopedia_of_Database_Systems], page numbered 4297 + Up: [probabilistic_databases], [database_model] diff --git a/probabilistic_database_neighboring_fields b/probabilistic_database_neighboring_fields @@ -0,0 +1,10 @@ +# Probabilistic database neighboring fields + +- [graphical_models] +- [knowledge_compilation] +- other [uncertain_data] / [incomplete_data] + - recent survey on incomplete data: [console2020coping] +- [network_reliability] problem ([all_terminal_network_reliability], etc.) +- [shapley_value] computation or [query_resilience] ([reshef2020impact]) and other such measures + +Up: [probabilistic_databases] diff --git a/probabilistic_databases b/probabilistic_databases @@ -0,0 +1,30 @@ +# Probabilistic databases + +- [probabilistic_database_model], +- [probabilistic_database_neighboring_fields] +- [provenance] / [lineage] + - [semirings] + - tractable [circuit] representations + - lower bounds from [amarilli2019connecting] +- [probabilistic_query_evaluation] + - [self-join-free_CQs] + - [UCQs]: [pqe_ucq] [dalvi2012dichotomy] + - [q9_conjecture]: [monet2020solving] + - [recursive_queries]: [amarilli2020dichotomy] +- [pqe_treelike] + - [pqe_MSO], via [provenance_circuits] + - historical motivation: [probabilistic_XML] + - [lower_bounds] in [amarilli2016tractable] +- [pqe_combined] +- [pqe_unweighted] + - [kenig2020dichotomy] + - [amarilli2022uniform] + - [symmetric_model_counting] +- [pqe_new_directions] + +- [pqe_applications] +- [probabilistic_databases_practice] + +See also: [relational_algebra], [relational_calculus] + +Up: [database_theory] diff --git a/quantitative b/quantitative @@ -0,0 +1,5 @@ +# Quantitative + +- [quantitative_mso] + +Up: [logic] diff --git a/representation_system b/representation_system @@ -0,0 +1,11 @@ +# Representation system + +A way to represent *uncertain data*: you have [representations], and each representation is a concise representation of a set of [possible_worlds]. For instance: + +- [NULLs] +- [v_tables] +- [c_tables] + +Presented in [imielinski1984incomplete] + +Up: [uncertain_data] diff --git a/semiring_idempotent b/semiring_idempotent @@ -1,10 +1,7 @@ # Idempotent semiring -A [semiring] satisfying the equation a+a = a for every a, i.e., [additively_idempotent] - -Not the case of all [semirings], e.g., not the [natural_numbers] - -Also [semiring_multiplicative_idempotent] +- [semiring_additively_idempotent] +- [semiring_multiplicative_idempotent] Up: [semiring], [idempotent] diff --git a/sjfcq b/sjfcq @@ -6,4 +6,4 @@ Up: [conjunctive_query], [self_join] -Aliases: self join free CQ, self join free CQs, selfjoin free CQ, selfjoin free CQs, cq self join free, cqs self join free +Aliases: self join free CQ, self join free CQs, selfjoin free CQ, selfjoin free CQs, cq self join free, cqs self join free, self-join-free CQ, self-join-free CQs diff --git a/state_complexity b/state_complexity @@ -0,0 +1,13 @@ +# State complexity + +https://en.wikipedia.org/wiki/State_complexity + +- For [automaton_complement] of an [automaton] with n [states] on a binary alphabet you may need 2^n states +- [minimization] / [canonical_automata] + - for [DFAs]: can be done in [PTIME] + - (quibble about whether it should be [complete_automata] or not) + - for [NFAs]: [pspace]-complete +- [upward_closure_state_complexity] +- [downward_closure_state_complexity] + +Up: [automata] diff --git a/tdta b/tdta @@ -0,0 +1,21 @@ +# tDTA + +Defined by a set of [states], an [initial_state], a set of [final_states], and a [transition_function] describing the state of the children of each tree node as a function of the state of the node and the label of the node. + +[acceptance_condition]: all [leaves] are labeled with a [final_state] + +The [tree_languages] that can be recognized by tDTAs are a proper subset of the [regular_tree_languages] +- In particular, if such an automaton accepts f(a,b) and f(a',b') then they accept f(a,b') and f(a',b) + +To understand the [expressive_power] of such [automata]: they only depend on the [word_language] of the [paths] from the [root] to the [leaves] in the input [tree] +- A [tree] t is accepted by a tDTA A if and only if the set of root-to-leaf [paths] of t is included in the set of root-to-leaf paths of the [trees] accepted by A + +Membership to the class of languages recognized by tDTAs is [decidable]. Generalization: [Boolean_closure_tDTA] + +Generalization: [tDTA_set_acceptance] + +Up: [tree_automaton_top_down], [automata_deterministic] + +See also: [bDTA], [tNTA], [tUTA] + +Aliases: deterministic top-down tree automaton diff --git a/tree_automaton b/tree_automaton @@ -5,9 +5,7 @@ Defines [regular_tree_language] ## Types - [tree_automaton_bottom_up] -- [tree_automaton_top_down]: - - [automata_deterministic] leads to a weaker class of languages - - [unambiguous]: is the same as unambiguous bottom-up (the unambiguity condition is symmetric) +- [tree_automaton_top_down] ## Variants diff --git a/tree_automaton_bottom_up b/tree_automaton_bottom_up @@ -2,7 +2,11 @@ - [initialization_function] / [initialization_relation] - [transition_function] / [transition_relation] -- can be [automaton_deterministic] ([bDTA]) or [automaton_nondeterministic] ([bNTA]) -- can be [automaton_unambiguous] ([bUTA]) + +types: + +- [automaton_deterministic]: [bDTA] +- [automaton_unambiguous]: [bUTA] +- [automaton_nondeterministic]: [bNTA] Up: [tree_automaton], [bottom_up] diff --git a/tree_automaton_top_down b/tree_automaton_top_down @@ -0,0 +1,12 @@ +# Tree automaton top down + +- [automata_deterministic]: [tDTA] + - leads to a weaker class of languages + - [Boolean_closure]: [Boolean_closure_tDTA] +- [unambiguous]: [tUTA] + - has same [expressiveness] as [bUTA] + - (the unambiguity condition is symmetric) +- [nondeterministic]: [tNTA] + - has same [expressiveness] as [bNTA] + +Up: [tree_automaton] diff --git a/uncertain_data b/uncertain_data @@ -2,5 +2,9 @@ - [inconsistency] - [certain_answers] +- [possible_answers] +- [representation_system] +- [consistent_query_answering] +- [open_world_query_answering] Up: [probabilistic_databases]