Title
Algorithms and conditional lower bounds for planning problems
Abstract
We consider planning problems for graphs, Markov Decision Processes (MDPs), and games on graphs in an explicit state space. While graphs represent the most basic planning model, MDPs represent interaction with nature and games on graphs represent interaction with an adversarial environment. We consider two planning problems with k different target sets: (a) the coverage problem asks whether there is a plan for each individual target set; and (b) the sequential target reachability problem asks whether the targets can be reached in a given sequence. For the coverage problem, we present a linear-time algorithm for graphs, and quadratic conditional lower bound for MDPs and games on graphs. For the sequential target problem, we present a linear-time algorithm for graphs, a sub-quadratic algorithm for MDPs, and a quadratic conditional lower bound for games on graphs. Our results with conditional lower bounds, based on the boolean matrix multiplication (BMM) conjecture and strong exponential time hypothesis (SETH), establish (i) model-separation results showing that for the coverage problem MDPs and games on graphs are harder than graphs, and for the sequential reachability problem games on graphs are harder than MDPs and graphs; and (ii) problem-separation results showing that for MDPs the coverage problem is harder than the sequential target problem.
Year
DOI
Venue
2021
10.1016/j.artint.2021.103499
Artificial Intelligence
Keywords
DocType
Volume
Graph games,Conditional lower bounds,Adversarial planning,Strong exponential time hypothesis,Probabilistic planning
Journal
297
Issue
ISSN
Citations 
1
0004-3702
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Krishnendu Chatterjee12179162.09
Wolfgang Dvorák227124.57
Monika Rauch Henzinger34307481.86
Alexander Svozil401.35