[{"title":"A symbolic SAT based algorithm for almost sure reachability with small strategies in POMDPs","day":"02","OA_type":"green","department":[{"_id":"KrCh"},{"_id":"ToHe"}],"project":[{"call_identifier":"FWF","grant_number":"P 23499-N23","_id":"2584A770-B435-11E9-9278-68D0E5697425","name":"Modern Graph Algorithmic Techniques in Formal Verification"},{"_id":"25832EC2-B435-11E9-9278-68D0E5697425","call_identifier":"FWF","grant_number":"S 11407_N23","name":"Rigorous Systems Engineering"},{"grant_number":"279307","call_identifier":"FP7","_id":"2581B60A-B435-11E9-9278-68D0E5697425","name":"Quantitative Graph Games: Theory and Applications"}],"author":[{"id":"2E5DCA20-F248-11E8-B48F-1D18A9856A87","first_name":"Krishnendu","orcid":"0000-0002-4561-241X","last_name":"Chatterjee","full_name":"Chatterjee, Krishnendu"},{"first_name":"Martin","id":"3624234E-F248-11E8-B48F-1D18A9856A87","last_name":"Chmelik","full_name":"Chmelik, Martin"},{"full_name":"Davies, Jessica","last_name":"Davies","first_name":"Jessica","id":"378E0060-F248-11E8-B48F-1D18A9856A87"}],"oa_version":"Preprint","date_updated":"2025-06-25T11:52:14Z","intvolume":"      2016","abstract":[{"text":"POMDPs are standard models for probabilistic planning problems, where an agent interacts with an uncertain environment. We study the problem of almost-sure reachability, where given a set of target states, the question is to decide whether there is a policy to ensure that the target set is reached with probability 1 (almost-surely). While in general the problem is EXPTIMEcomplete, in many practical cases policies with a small amount of memory suffice. Moreover, the existing solution to the problem is explicit, which first requires to construct explicitly an exponential reduction to a belief-support MDP. In this work, we first study the existence of observation-stationary strategies, which is NP-complete, and then small-memory strategies. We present a symbolic algorithm by an efficient encoding to SAT and using a SAT solver for the problem. We report experimental results demonstrating the scalability of our symbolic (SAT-based) approach. © 2016, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved.","lang":"eng"}],"main_file_link":[{"url":"https://doi.org/10.48550/arXiv.1511.08456","open_access":"1"}],"date_created":"2018-12-11T11:50:30Z","status":"public","acknowledgement":"The research was partly supported by Austrian Science Fund (FWF) Grant No P23499-N23, FWF NFN Grant No S11407-N23 (RiSE), ERC Start grant (279307: Graph Games), and Microsoft faculty fellows award.","article_processing_charge":"No","ec_funded":1,"conference":{"start_date":"2016-02-12","location":"Phoenix, AZ, United States","end_date":"2016-02-17","name":"AAAI: Conference on Artificial Intelligence"},"publication":"Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence","related_material":{"link":[{"relation":"table_of_contents","url":"https://dl.acm.org/citation.cfm?id=3016355"}],"record":[{"status":"public","relation":"earlier_version","id":"5443"}]},"publist_id":"6191","arxiv":1,"month":"12","_id":"1166","OA_place":"repository","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication_status":"published","citation":{"ieee":"K. Chatterjee, M. Chmelik, and J. Davies, “A symbolic SAT based algorithm for almost sure reachability with small strategies in POMDPs,” in <i>Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence</i>, Phoenix, AZ, United States, 2016, vol. 2016, pp. 3225–3232.","ama":"Chatterjee K, Chmelik M, Davies J. A symbolic SAT based algorithm for almost sure reachability with small strategies in POMDPs. In: <i>Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence</i>. Vol 2016. AAAI Press; 2016:3225-3232. doi:<a href=\"https://doi.org/10.1609/aaai.v30i1.10422\">10.1609/aaai.v30i1.10422</a>","apa":"Chatterjee, K., Chmelik, M., &#38; Davies, J. (2016). A symbolic SAT based algorithm for almost sure reachability with small strategies in POMDPs. In <i>Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence</i> (Vol. 2016, pp. 3225–3232). Phoenix, AZ, United States: AAAI Press. <a href=\"https://doi.org/10.1609/aaai.v30i1.10422\">https://doi.org/10.1609/aaai.v30i1.10422</a>","mla":"Chatterjee, Krishnendu, et al. “A Symbolic SAT Based Algorithm for Almost Sure Reachability with Small Strategies in POMDPs.” <i>Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence</i>, vol. 2016, AAAI Press, 2016, pp. 3225–32, doi:<a href=\"https://doi.org/10.1609/aaai.v30i1.10422\">10.1609/aaai.v30i1.10422</a>.","ista":"Chatterjee K, Chmelik M, Davies J. 2016. A symbolic SAT based algorithm for almost sure reachability with small strategies in POMDPs. Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence. AAAI: Conference on Artificial Intelligence vol. 2016, 3225–3232.","chicago":"Chatterjee, Krishnendu, Martin Chmelik, and Jessica Davies. “A Symbolic SAT Based Algorithm for Almost Sure Reachability with Small Strategies in POMDPs.” In <i>Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence</i>, 2016:3225–32. AAAI Press, 2016. <a href=\"https://doi.org/10.1609/aaai.v30i1.10422\">https://doi.org/10.1609/aaai.v30i1.10422</a>.","short":"K. Chatterjee, M. Chmelik, J. Davies, in:, Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence, AAAI Press, 2016, pp. 3225–3232."},"type":"conference","volume":2016,"corr_author":"1","oa":1,"language":[{"iso":"eng"}],"doi":"10.1609/aaai.v30i1.10422","publisher":"AAAI Press","date_published":"2016-12-02T00:00:00Z","external_id":{"arxiv":["1511.08456"]},"page":"3225 - 3232","quality_controlled":"1","year":"2016"},{"publisher":"IST Austria","doi":"10.15479/AT:IST-2015-325-v2-1","date_published":"2015-11-06T00:00:00Z","language":[{"iso":"eng"}],"status":"public","file_date_updated":"2020-07-14T12:46:57Z","oa":1,"date_created":"2018-12-12T11:39:22Z","file":[{"relation":"main_file","creator":"system","date_created":"2018-12-12T11:53:05Z","date_updated":"2020-07-14T12:46:57Z","content_type":"application/pdf","file_size":412379,"file_id":"5466","checksum":"f0fa31ad8161ed655137e94012123ef9","access_level":"open_access","file_name":"IST-2015-325-v2+1_main.pdf"}],"publication_identifier":{"issn":["2664-1690"]},"page":"23","pubrep_id":"362","related_material":{"record":[{"relation":"later_version","id":"1166","status":"public"}]},"year":"2015","day":"06","alternative_title":["IST Austria Technical Report"],"month":"11","ddc":["000"],"title":"A symbolic SAT-based algorithm for almost-sure reachability with small strategies in POMDPs","department":[{"_id":"KrCh"}],"_id":"5443","has_accepted_license":"1","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","author":[{"first_name":"Krishnendu","id":"2E5DCA20-F248-11E8-B48F-1D18A9856A87","orcid":"0000-0002-4561-241X","last_name":"Chatterjee","full_name":"Chatterjee, Krishnendu"},{"full_name":"Chmelik, Martin","last_name":"Chmelik","first_name":"Martin","id":"3624234E-F248-11E8-B48F-1D18A9856A87"},{"last_name":"Davies","full_name":"Davies, Jessica","id":"378E0060-F248-11E8-B48F-1D18A9856A87","first_name":"Jessica"}],"abstract":[{"lang":"eng","text":"POMDPs are standard models for probabilistic planning problems, where an agent interacts with an uncertain environment. We study the problem of almost-sure reachability, where given a set of target states, the question is to decide whether there is a policy to ensure that the target set is reached with probability 1 (almost-surely). While in general the problem is EXPTIME-complete, in many practical cases policies with a small amount of memory suffice. Moreover, the existing solution to the problem is explicit, which first requires to construct explicitly an exponential reduction to a belief-support MDP. In this work, we first study the existence of observation-stationary strategies, which is NP-complete, and then small-memory strategies. We present a symbolic algorithm by an efficient encoding to SAT and using a SAT solver for the problem. We report experimental results demonstrating the scalability of our symbolic (SAT-based) approach."}],"type":"technical_report","date_updated":"2025-06-25T11:52:13Z","citation":{"apa":"Chatterjee, K., Chmelik, M., &#38; Davies, J. (2015). <i>A symbolic SAT-based algorithm for almost-sure reachability with small strategies in POMDPs</i>. IST Austria. <a href=\"https://doi.org/10.15479/AT:IST-2015-325-v2-1\">https://doi.org/10.15479/AT:IST-2015-325-v2-1</a>","ama":"Chatterjee K, Chmelik M, Davies J. <i>A Symbolic SAT-Based Algorithm for Almost-Sure Reachability with Small Strategies in POMDPs</i>. IST Austria; 2015. doi:<a href=\"https://doi.org/10.15479/AT:IST-2015-325-v2-1\">10.15479/AT:IST-2015-325-v2-1</a>","ieee":"K. Chatterjee, M. Chmelik, and J. Davies, <i>A symbolic SAT-based algorithm for almost-sure reachability with small strategies in POMDPs</i>. IST Austria, 2015.","ista":"Chatterjee K, Chmelik M, Davies J. 2015. A symbolic SAT-based algorithm for almost-sure reachability with small strategies in POMDPs, IST Austria, 23p.","mla":"Chatterjee, Krishnendu, et al. <i>A Symbolic SAT-Based Algorithm for Almost-Sure Reachability with Small Strategies in POMDPs</i>. IST Austria, 2015, doi:<a href=\"https://doi.org/10.15479/AT:IST-2015-325-v2-1\">10.15479/AT:IST-2015-325-v2-1</a>.","chicago":"Chatterjee, Krishnendu, Martin Chmelik, and Jessica Davies. <i>A Symbolic SAT-Based Algorithm for Almost-Sure Reachability with Small Strategies in POMDPs</i>. IST Austria, 2015. <a href=\"https://doi.org/10.15479/AT:IST-2015-325-v2-1\">https://doi.org/10.15479/AT:IST-2015-325-v2-1</a>.","short":"K. Chatterjee, M. Chmelik, J. Davies, A Symbolic SAT-Based Algorithm for Almost-Sure Reachability with Small Strategies in POMDPs, IST Austria, 2015."},"oa_version":"Published Version","publication_status":"published"}]