Abstract
Two-player quantitative zero-sum games provide a natural framework to synthesize controllers with performance guarantees for reactive systems within an uncontrollable environment. Classical settings include mean-payoff games, where the objective is to optimize the long-run average gain per action, and energy games, where the system has to avoid running out of energy. We study average-energy games, where the goal is to optimize the long-run average of the accumulated energy. We show that this objective arises naturally in several applications, and that it yields interesting connections with previous concepts in the literature. We prove that deciding the winner in such games is in \(\mathsf{NP}\cap \mathsf{coNP}\) and at least as hard as solving mean-payoff games, and we establish that memoryless strategies suffice to win. We also consider the case where the system has to minimize the average-energy while maintaining the accumulated energy within predefined bounds at all times: this corresponds to operating with a finite-capacity storage for energy. We give results for one-player and two-player games, and establish complexity bounds and memory requirements.
Similar content being viewed by others
Notes
We slightly abuse the notation as we see cycles as sequences of edges. The concatenation of cycles \(\mathcal {C}_{a} = s\,s'\ldots {} s\) and \(\mathcal {C}_{b} = s\,s'' \ldots {} s\) is to be understood as its natural interpretation \(\mathcal {C}_{a} \cdot \mathcal {C}_{b} = s\,s'\ldots {} s\,s'' \ldots {} s\): the origin state s only appears once in the middle and not twice as it would with \(\mathcal {C}_{a}\) and \(\mathcal {C}_{b}\) seen as true sequences of states.
Observe that given a state in \(G''\), it is indeed possible to build any neighboring state using only E and w from the original game: one can effectively build the graph \(G''\) on-the-fly.
In \({ EG}_{{ LU}}\) games with only \(\mathcal {P}_{2} \) (i.e., \(S_{1} = \emptyset \)), \(\mathcal {P}_{2} \) does not need memory to play as he can pick beforehand which of the energy bounds (lower or upper) he will transgress, and then do so with a memoryless strategy.
References
Aminof, B., Rubin, S.: First cycle games. In: Proceedings of SR, EPTCS 146, pp. 83–90 (2014)
Björklund, H., Sandberg, S., Vorobyov, S.: Memoryless determinacy of parity and mean payoff games: a simple proof. Theor. Comput. Sci. 310(1–3), 365–378 (2004)
Bloem, R., Chatterjee, K., Henzinger, T.A., Jobstmann, B.: Better quality in synthesis through quantitative objectives. In: Proceedings of CAV, LNCS 5643, pp 140–156. Springer, Berlin (2009)
Bohy, A., Bruyère, V., Filiot, E., Raskin, J.-F.: Synthesis from LTL specifications with mean-payoff objectives. In: Proceedings of of TACAS, LNCS 7795, pp. 169–184. Springer, Berlin (2013)
Boros, E., Elbassioni, K., Gurvich, V., Makino, K.: Markov decision processes and stochastic games with total effective payoff. In: Proceedings of STACS, LIPIcs 30, pp. 103–115. Schloss Dagstuhl—LZI (2015)
Bouyer, P., Fahrenberg, U., Larsen, K.G., Markey, N., Srba, J.: Infinite runs in weighted timed automata with energy constraints. In: Proceedings of FORMATS, LNCS 5215, pp. 33–47. Springer, Berlin (2008)
Bouyer, P., Markey, N., Randour, M., Larsen, K.G., Laursen, S.: Average-energy games. In: Proceedings of GandALF, EPTCS 193, pp. 1–15 (2015)
Brázdil, T., Klaška, D., Kučera, A., Novotný, P.: Minimizing running costs in consumption systems. In: Proceedings of CAV, LNCS 8559, pp. 457–472. Springer, Berlin (2014)
Brim, L., Chaloupka, J., Doyen, L., Gentilini, R., Raskin, J.-F.: Faster algorithms for mean-payoff games. Formal Methods Syst. Des. 38(2), 97–118 (2011)
Cassez, F., Jensen, J.J., Larsen, K.G., Raskin, J.-F., Reynier, P.-A.: Automatic synthesis of robust and optimal controllers—an industrial case study. In: Proceedings of HSCC, LNCS 5469, pp. 90–104. Springer, Berlin (2009)
Chakrabarti, A., de Alfaro, L., Henzinger, T.A., Stoelinga, M.: Resource interfaces. In: Proceedings of EMSOFT, LNCS 2855, pp. 117–133. Springer, Berlin (2003)
Chatterjee, K., Doyen, L.: Energy parity games. In: Proceedings of ICALP, LNCS 6199, pp. 599–610. Springer, Berlin (2010)
Chatterjee, K., Velner, Y.: Mean-payoff pushdown games. In: Proceedings of LICS, pp. 195–204. IEEE (2012)
Chatterjee, K., Prabhu, V.S.: Quantitative timed simulation functions and refinement metrics for real-time systems. In: Proceedings of HSCC, pp. 273–282. ACM (2013)
Chatterjee, K., Randour, M., Raskin, J.-F.: Strategy synthesis for multi-dimensional quantitative objectives. Acta Inf. 51(3–4), 129–163 (2014)
Chatterjee, K., Doyen, L., Randour, M., Raskin, J.-F.: Looking at mean-payoff and total-payoff through windows. Inf. Comput. 242, 25–52 (2015)
Ehrenfeucht, A., Mycielski, J.: Positional strategies for mean payoff games. Int. J. Game Theory 8(2), 109–113 (1979)
Fearnley, J., Jurdziński, M.: Reachability in two-clock timed automata is PSPACE-complete. In: Proceedings of ICALP, LNCS 7966, pp. 212–223. Springer, Berlin (2013)
Filar, J., Vrieze, K.: Competitive Markov Decision Processes. Springer, Berlin (1997)
Garey, M.R., Johnson, D.S.: Computers and Intractability: A Guide to the Theory of NP-Completeness. Freeman, New York (1979)
Gawlitza, T., Seidl, H.: Games through nested fixpoints. In: Proceedings of CAV, LNCS 5643, pp. 291–305. Springer, Berlin (2009)
Gimbert, H., Zielonka, W.: When can you play positionnaly? In: Proceedings of MFCS, LNCS 3153, pp. 686–697. Springer, Berlin (2004)
Gimbert, H., Zielonka, W.: Games where you can play optimally without any memory. In: Proceedings of CONCUR, LNCS 3653, pp. 428–442. Springer, Berlin (2005)
Grädel, E., Thomas, W., Wilke, T. (eds.): Automata, Logics, and Infinite Games: A Guide to Current Research, LNCS 2500. Springer, Berlin (2002)
Juhl, L., Larsen, K.G., Raskin, J.-F.: Optimal bounds for multiweighted and parametrised energy games. In: Theories of Programming and Formal Methods, LNCS 8051, pp. 244–255. Springer, Berlin (2013)
Jurdziński, M.: Deciding the winner in parity games is in UP\(\cap \)co-UP. Inf. Process. Lett. 68(3), 119–124 (1998)
Jurdziński, M., Sproston, J., Laroussinie, F.: Model checking probabilistic timed automata with one or two clocks. Logical Methods Comput. Sci. 4(3), 1–28 (2008)
Karp, R.M.: A characterization of the minimum cycle mean in a digraph. Discrete Math. 23(3), 309–311 (1978)
Kopczynski, E.: Half-positional determinacy of infinite games. In: Proceedings of ICALP, LNCS 4052, pp. 336–347. Springer, Berlin (2006)
Lafourcade, P., Lugiez, D., Treinen, R.: Intruder deduction for AC-like equational theories with homomorphisms. Research Report LSV-04-16, Laboratoire Spécification et Vérification, ENS Cachan, France (2004)
Lafourcade, P., Lugiez, D., Treinen, R.: Intruder deduction for AC-like equational theories with homomorphisms. In: Proceedings of RTA, LNCS 3467, pp. 308–322. Springer, Berlin (2005)
Larsen, K.G., Laursen, S., Zimmermann, M.: Limit your consumption! Finding bounds in average-energy games. In: Proceedings of QAPL, EPTCS (2016)
Randour, M.: Automated synthesis of reliable and efficient systems through game theory: a case study. In: Proceedings of the European Conference on Complex Systems 2012, Springer Proceedings in Complexity XVII, pp. 731–738. Springer, Berlin (2013)
Randour, M.: Synthesis in Multi-Criteria Quantitative Games. Ph.D. Thesis, Université de Mons, Belgium (2014)
Sipser, M.: Introduction to the Theory of Computation. PWS Publishing Company, Boston (1997)
Thuijsman, F., Vrieze, O.J.: The bad match; a total reward stochastic game. OR Spektrum 9(2), 93–99 (1987)
Velner, Y., Chatterjee, K., Doyen, L., Henzinger, T.A., Rabinovich, A.M., Raskin, J.-F.: The complexity of multi-mean-payoff and multi-energy games. Inf. Comput. 241, 177–196 (2015)
Zwick, U., Paterson, M.: The complexity of mean payoff games on graphs. Theor. Comput. Sci. 158(1–2), 343–359 (1996)
Author information
Authors and Affiliations
Corresponding author
Additional information
Work partially supported by European project CASSTING (FP7-ICT-601148) and ERC project EQualIS (StG-308087). Mickael Randour is an F.R.S.-FNRS Postdoctoral Researcher.
Rights and permissions
About this article
Cite this article
Bouyer, P., Markey, N., Randour, M. et al. Average-energy games. Acta Informatica 55, 91–127 (2018). https://doi.org/10.1007/s00236-016-0274-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00236-016-0274-1