--- _id: '5377' abstract: - lang: eng text: 'Two-player games on graphs are central in many problems in formal verification and program analysis such as synthesis and verification of open systems. In this work we consider solving recursive game graphs (or pushdown game graphs) that can model the control flow of sequential programs with recursion. While pushdown games have been studied before with qualitative objectives, such as reachability and ω-regular objectives, in this work we study for the first time such games with the most well-studied quantitative objective, namely, mean-payoff objectives. In pushdown games two types of strategies are relevant: (1) global strategies, that depend on the entire global history; and (2) modular strategies, that have only local memory and thus do not depend on the context of invocation, but only on the history of the current invocation of the module. Our main results are as follows: (1) One-player pushdown games with mean-payoff objectives under global strategies are decidable in polynomial time. (2) Two- player pushdown games with mean-payoff objectives under global strategies are undecidable. (3) One-player pushdown games with mean-payoff objectives under modular strategies are NP- hard. (4) Two-player pushdown games with mean-payoff objectives under modular strategies can be solved in NP (i.e., both one-player and two-player pushdown games with mean-payoff objectives under modular strategies are NP-complete). We also establish the optimal strategy complexity showing that global strategies for mean-payoff objectives require infinite memory even in one-player pushdown games; and memoryless modular strategies are sufficient in two- player pushdown games. Finally we also show that all the problems have the same complexity if the stack boundedness condition is added, where along with the mean-payoff objective the player must also ensure that the stack height is bounded.' alternative_title: - IST Austria Technical Report author: - first_name: Krishnendu full_name: Chatterjee, Krishnendu id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87 last_name: Chatterjee orcid: 0000-0002-4561-241X - first_name: Yaron full_name: Velner, Yaron last_name: Velner citation: ama: Chatterjee K, Velner Y. Mean-Payoff Pushdown Games. IST Austria; 2012. doi:10.15479/AT:IST-2012-0002 apa: Chatterjee, K., & Velner, Y. (2012). Mean-payoff pushdown games. IST Austria. https://doi.org/10.15479/AT:IST-2012-0002 chicago: Chatterjee, Krishnendu, and Yaron Velner. Mean-Payoff Pushdown Games. IST Austria, 2012. https://doi.org/10.15479/AT:IST-2012-0002. ieee: K. Chatterjee and Y. Velner, Mean-payoff pushdown games. IST Austria, 2012. ista: Chatterjee K, Velner Y. 2012. Mean-payoff pushdown games, IST Austria, 33p. mla: Chatterjee, Krishnendu, and Yaron Velner. Mean-Payoff Pushdown Games. IST Austria, 2012, doi:10.15479/AT:IST-2012-0002. short: K. Chatterjee, Y. Velner, Mean-Payoff Pushdown Games, IST Austria, 2012. date_created: 2018-12-12T11:38:59Z date_published: 2012-07-02T00:00:00Z date_updated: 2023-02-23T11:05:50Z day: '02' ddc: - '000' - '005' department: - _id: KrCh doi: 10.15479/AT:IST-2012-0002 file: - access_level: open_access checksum: a03c08c1589dbb0c96183a8bcf3ab240 content_type: application/pdf creator: system date_created: 2018-12-12T11:54:00Z date_updated: 2020-07-14T12:46:38Z file_id: '5522' file_name: IST-2012-002_IST-2012-0002.pdf file_size: 592098 relation: main_file file_date_updated: 2020-07-14T12:46:38Z has_accepted_license: '1' language: - iso: eng month: '07' oa: 1 oa_version: Published Version page: '33' publication_identifier: issn: - 2664-1690 publication_status: published publisher: IST Austria pubrep_id: '10' related_material: record: - id: '2956' relation: later_version status: public status: public title: Mean-payoff pushdown games type: technical_report user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2012' ... --- _id: '5378' abstract: - lang: eng text: 'One central issue in the formal design and analysis of reactive systems is the notion of refinement that asks whether all behaviors of the implementation is allowed by the specification. The local interpretation of behavior leads to the notion of simulation. Alternating transition systems (ATSs) provide a general model for composite reactive systems, and the simulation relation for ATSs is known as alternating simulation. The simulation relation for fair transition systems is called fair simulation. In this work our main contributions are as follows: (1) We present an improved algorithm for fair simulation with Büchi fairness constraints; our algorithm requires O(n3 · m) time as compared to the previous known O(n6)-time algorithm, where n is the number of states and m is the number of transitions. (2) We present a game based algorithm for alternating simulation that requires O(m2)-time as compared to the previous known O((n · m)2)-time algorithm, where n is the number of states and m is the size of transition relation. (3) We present an iterative algorithm for alternating simulation that matches the time complexity of the game based algorithm, but is more space efficient than the game based algorithm.' alternative_title: - IST Austria Technical Report author: - first_name: Krishnendu full_name: Chatterjee, Krishnendu id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87 last_name: Chatterjee orcid: 0000-0002-4561-241X - first_name: Siddhesh full_name: Chaubal, Siddhesh last_name: Chaubal - first_name: Pritish full_name: Kamath, Pritish last_name: Kamath citation: ama: Chatterjee K, Chaubal S, Kamath P. Faster Algorithms for Alternating Refinement Relations. IST Austria; 2012. doi:10.15479/AT:IST-2012-0001 apa: Chatterjee, K., Chaubal, S., & Kamath, P. (2012). Faster algorithms for alternating refinement relations. IST Austria. https://doi.org/10.15479/AT:IST-2012-0001 chicago: Chatterjee, Krishnendu, Siddhesh Chaubal, and Pritish Kamath. Faster Algorithms for Alternating Refinement Relations. IST Austria, 2012. https://doi.org/10.15479/AT:IST-2012-0001. ieee: K. Chatterjee, S. Chaubal, and P. Kamath, Faster algorithms for alternating refinement relations. IST Austria, 2012. ista: Chatterjee K, Chaubal S, Kamath P. 2012. Faster algorithms for alternating refinement relations, IST Austria, 21p. mla: Chatterjee, Krishnendu, et al. Faster Algorithms for Alternating Refinement Relations. IST Austria, 2012, doi:10.15479/AT:IST-2012-0001. short: K. Chatterjee, S. Chaubal, P. Kamath, Faster Algorithms for Alternating Refinement Relations, IST Austria, 2012. date_created: 2018-12-12T11:38:59Z date_published: 2012-07-04T00:00:00Z date_updated: 2023-02-23T12:21:38Z day: '04' ddc: - '000' - '005' department: - _id: KrCh doi: 10.15479/AT:IST-2012-0001 file: - access_level: open_access checksum: ec8d1857cc7095d3de5107a0162ced37 content_type: application/pdf creator: system date_created: 2018-12-12T11:53:28Z date_updated: 2020-07-14T12:46:39Z file_id: '5489' file_name: IST-2012-0001_IST-2012-0001.pdf file_size: 394256 relation: main_file file_date_updated: 2020-07-14T12:46:39Z has_accepted_license: '1' language: - iso: eng month: '07' oa: 1 oa_version: Published Version page: '21' publication_identifier: issn: - 2664-1690 publication_status: published publisher: IST Austria pubrep_id: '14' related_material: record: - id: '497' relation: later_version status: public status: public title: Faster algorithms for alternating refinement relations type: technical_report user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2012' ... --- _id: '2955' abstract: - lang: eng text: 'We consider two-player stochastic games played on finite graphs with reachability objectives where the first player tries to ensure a target state to be visited almost-surely (i.e., with probability 1), or positively (i.e., with positive probability), no matter the strategy of the second player. We classify such games according to the information and the power of randomization available to the players. On the basis of information, the game can be one-sided with either (a) player 1, or (b) player 2 having partial observation (and the other player has perfect observation), or two-sided with (c) both players having partial observation. On the basis of randomization, the players (a) may not be allowed to use randomization (pure strategies), or (b) may choose a probability distribution over actions but the actual random choice is external and not visible to the player (actions invisible), or (c) may use full randomization. Our main results for pure strategies are as follows. (1) For one-sided games with player 1 having partial observation we show that (in contrast to full randomized strategies) belief-based (subset-construction based) strategies are not sufficient, and we present an exponential upper bound on memory both for almostsure and positive winning strategies; we show that the problem of deciding the existence of almost-sure and positive winning strategies for player 1 is EXPTIME-complete. (2) For one-sided games with player 2 having partial observation we show that non-elementary memory is both necessary and sufficient for both almost-sure and positive winning strategies. (3) We show that for the general (two-sided) case finite-memory strategies are sufficient for both positive and almost-sure winning, and at least non-elementary memory is required. We establish the equivalence of the almost-sure winning problems for pure strategies and for randomized strategies with actions invisible. Our equivalence result exhibits serious flaws in previous results of the literature: we show a non-elementary memory lower bound for almost-sure winning whereas an exponential upper bound was previously claimed.' acknowledgement: 'This work was partially supported by FWF Grant No P 23499-N23, FWF NFN Grant No S11407-N23 (RiSE), ERC Start grant (279307: Graph Games), and Microsoft faculty fellows award.' article_number: '6280436' author: - first_name: Krishnendu full_name: Chatterjee, Krishnendu id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87 last_name: Chatterjee orcid: 0000-0002-4561-241X - first_name: Laurent full_name: Doyen, Laurent last_name: Doyen citation: ama: 'Chatterjee K, Doyen L. Partial-observation stochastic games: How to win when belief fails. In: Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. IEEE; 2012. doi:10.1109/LICS.2012.28' apa: 'Chatterjee, K., & Doyen, L. (2012). Partial-observation stochastic games: How to win when belief fails. In Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. Dubrovnik, Croatia: IEEE. https://doi.org/10.1109/LICS.2012.28' chicago: 'Chatterjee, Krishnendu, and Laurent Doyen. “Partial-Observation Stochastic Games: How to Win When Belief Fails.” In Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. IEEE, 2012. https://doi.org/10.1109/LICS.2012.28.' ieee: 'K. Chatterjee and L. Doyen, “Partial-observation stochastic games: How to win when belief fails,” in Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science, Dubrovnik, Croatia, 2012.' ista: 'Chatterjee K, Doyen L. 2012. Partial-observation stochastic games: How to win when belief fails. Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. LICS: Logic in Computer Science, 6280436.' mla: 'Chatterjee, Krishnendu, and Laurent Doyen. “Partial-Observation Stochastic Games: How to Win When Belief Fails.” Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science, 6280436, IEEE, 2012, doi:10.1109/LICS.2012.28.' short: K. Chatterjee, L. Doyen, in:, Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science, IEEE, 2012. conference: end_date: 2012-06-28 location: Dubrovnik, Croatia name: 'LICS: Logic in Computer Science' start_date: 2012-06-25 date_created: 2018-12-11T12:00:32Z date_published: 2012-08-23T00:00:00Z date_updated: 2023-02-23T12:23:43Z day: '23' department: - _id: KrCh doi: 10.1109/LICS.2012.28 ec_funded: 1 external_id: arxiv: - '1107.2141' language: - iso: eng main_file_link: - open_access: '1' url: http://arxiv.org/abs/1107.2141 month: '08' oa: 1 oa_version: Preprint project: - _id: 2584A770-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P 23499-N23 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 - _id: 2581B60A-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '279307' name: 'Quantitative Graph Games: Theory and Applications' - _id: 2587B514-B435-11E9-9278-68D0E5697425 name: Microsoft Research Faculty Fellowship publication: Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science publication_status: published publisher: IEEE publist_id: '3771' quality_controlled: '1' related_material: record: - id: '2211' relation: later_version status: public - id: '5381' relation: earlier_version status: public scopus_import: 1 status: public title: 'Partial-observation stochastic games: How to win when belief fails' type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2012' ... --- _id: '3341' abstract: - lang: eng text: 'We consider two-player stochastic games played on a finite state space for an infinite number of rounds. The games are concurrent: in each round, the two players (player 1 and player 2) choose their moves independently and simultaneously; the current state and the two moves determine a probability distribution over the successor states. We also consider the important special case of turn-based stochastic games where players make moves in turns, rather than concurrently. We study concurrent games with \omega-regular winning conditions specified as parity objectives. The value for player 1 for a parity objective is the maximal probability with which the player can guarantee the satisfaction of the objective against all strategies of the opponent. We study the problem of continuity and robustness of the value function in concurrent and turn-based stochastic parity gameswith respect to imprecision in the transition probabilities. We present quantitative bounds on the difference of the value function (in terms of the imprecision of the transition probabilities) and show the value continuity for structurally equivalent concurrent games (two games are structurally equivalent if the support of the transition function is same and the probabilities differ). We also show robustness of optimal strategies for structurally equivalent turn-based stochastic parity games. Finally we show that the value continuity property breaks without the structurally equivalent assumption (even for Markov chains) and show that our quantitative bound is asymptotically optimal. Hence our results are tight (the assumption is both necessary and sufficient) and optimal (our quantitative bound is asymptotically optimal).' alternative_title: - LNCS author: - first_name: Krishnendu full_name: Chatterjee, Krishnendu id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87 last_name: Chatterjee orcid: 0000-0002-4561-241X citation: ama: 'Chatterjee K. Robustness of structurally equivalent concurrent parity games. In: Vol 7213. Springer; 2012:270-285. doi:10.1007/978-3-642-28729-9_18' apa: 'Chatterjee, K. (2012). Robustness of structurally equivalent concurrent parity games (Vol. 7213, pp. 270–285). Presented at the FoSSaCS: Foundations of Software Science and Computation Structures, Tallinn, Estonia: Springer. https://doi.org/10.1007/978-3-642-28729-9_18' chicago: Chatterjee, Krishnendu. “Robustness of Structurally Equivalent Concurrent Parity Games,” 7213:270–85. Springer, 2012. https://doi.org/10.1007/978-3-642-28729-9_18. ieee: 'K. Chatterjee, “Robustness of structurally equivalent concurrent parity games,” presented at the FoSSaCS: Foundations of Software Science and Computation Structures, Tallinn, Estonia, 2012, vol. 7213, pp. 270–285.' ista: 'Chatterjee K. 2012. Robustness of structurally equivalent concurrent parity games. FoSSaCS: Foundations of Software Science and Computation Structures, LNCS, vol. 7213, 270–285.' mla: Chatterjee, Krishnendu. Robustness of Structurally Equivalent Concurrent Parity Games. Vol. 7213, Springer, 2012, pp. 270–85, doi:10.1007/978-3-642-28729-9_18. short: K. Chatterjee, in:, Springer, 2012, pp. 270–285. conference: end_date: 2012-04-01 location: Tallinn, Estonia name: 'FoSSaCS: Foundations of Software Science and Computation Structures' start_date: 2012-03-24 date_created: 2018-12-11T12:02:46Z date_published: 2012-03-22T00:00:00Z date_updated: 2023-02-23T12:23:46Z day: '22' department: - _id: KrCh doi: 10.1007/978-3-642-28729-9_18 ec_funded: 1 external_id: arxiv: - '1107.2009' intvolume: ' 7213' language: - iso: eng main_file_link: - open_access: '1' url: http://arxiv.org/abs/1107.2009 month: '03' oa: 1 oa_version: Preprint page: 270 - 285 project: - _id: 2584A770-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P 23499-N23 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 - _id: 2581B60A-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '279307' name: 'Quantitative Graph Games: Theory and Applications' - _id: 2587B514-B435-11E9-9278-68D0E5697425 name: Microsoft Research Faculty Fellowship publication_status: published publisher: Springer publist_id: '3284' quality_controlled: '1' related_material: record: - id: '5382' relation: earlier_version status: public scopus_import: 1 status: public title: Robustness of structurally equivalent concurrent parity games type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 7213 year: '2012' ... --- _id: '2957' abstract: - lang: eng text: 'We consider probabilistic automata on infinite words with acceptance defined by parity conditions. We consider three qualitative decision problems: (i) the positive decision problem asks whether there is a word that is accepted with positive probability; (ii) the almost decision problem asks whether there is a word that is accepted with probability 1; and (iii) the limit decision problem asks whether words are accepted with probability arbitrarily close to 1. We unify and generalize several decidability results for probabilistic automata over infinite words, and identify a robust (closed under union and intersection) subclass of probabilistic automata for which all the qualitative decision problems are decidable for parity conditions. We also show that if the input words are restricted to lasso shape (regular) words, then the positive and almost problems are decidable for all probabilistic automata with parity conditions. For most decidable problems we show an optimal PSPACE-complete complexity bound.' article_number: '6280437' author: - first_name: Krishnendu full_name: Chatterjee, Krishnendu id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87 last_name: Chatterjee orcid: 0000-0002-4561-241X - first_name: Mathieu full_name: Tracol, Mathieu id: 3F54FA38-F248-11E8-B48F-1D18A9856A87 last_name: Tracol citation: ama: 'Chatterjee K, Tracol M. Decidable problems for probabilistic automata on infinite words. In: Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. IEEE; 2012. doi:10.1109/LICS.2012.29' apa: 'Chatterjee, K., & Tracol, M. (2012). Decidable problems for probabilistic automata on infinite words. In Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. Dubrovnik, Croatia : IEEE. https://doi.org/10.1109/LICS.2012.29' chicago: Chatterjee, Krishnendu, and Mathieu Tracol. “Decidable Problems for Probabilistic Automata on Infinite Words.” In Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. IEEE, 2012. https://doi.org/10.1109/LICS.2012.29. ieee: K. Chatterjee and M. Tracol, “Decidable problems for probabilistic automata on infinite words,” in Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science, Dubrovnik, Croatia , 2012. ista: 'Chatterjee K, Tracol M. 2012. Decidable problems for probabilistic automata on infinite words. Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science. LICS: Logic in Computer Science, 6280437.' mla: Chatterjee, Krishnendu, and Mathieu Tracol. “Decidable Problems for Probabilistic Automata on Infinite Words.” Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science, 6280437, IEEE, 2012, doi:10.1109/LICS.2012.29. short: K. Chatterjee, M. Tracol, in:, Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science, IEEE, 2012. conference: end_date: 2012-06-28 location: 'Dubrovnik, Croatia ' name: 'LICS: Logic in Computer Science' start_date: 2012-06-25 date_created: 2018-12-11T12:00:33Z date_published: 2012-08-23T00:00:00Z date_updated: 2023-02-23T12:23:51Z day: '23' department: - _id: KrCh doi: 10.1109/LICS.2012.29 ec_funded: 1 external_id: arxiv: - '1107.2091' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1107.2091 month: '08' oa: 1 oa_version: Preprint project: - _id: 2584A770-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P 23499-N23 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 - _id: 2581B60A-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '279307' name: 'Quantitative Graph Games: Theory and Applications' - _id: 2587B514-B435-11E9-9278-68D0E5697425 name: Microsoft Research Faculty Fellowship publication: Proceedings of the 2012 27th Annual ACM/IEEE Symposium on Logic in Computer Science publication_status: published publisher: IEEE publist_id: '3769' quality_controlled: '1' related_material: record: - id: '5384' relation: earlier_version status: public scopus_import: 1 status: public title: Decidable problems for probabilistic automata on infinite words type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2012' ...