---
res:
  bibo_abstract:
  - 'In two-player finite-state stochastic games of partial observation on graphs,
    in every state of the graph, the players simultaneously choose an action, and
    their joint actions determine a probability distribution over the successor states.
    The game is played for infinitely many rounds and thus the players construct an
    infinite path in the graph. We consider 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 to 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, (a)
    the players may not be allowed to use randomization (pure strategies), or (b)
    they may choose a probability distribution over actions but the actual random
    choice is external and not visible to the player (actions invisible), or (c) they
    may use full randomization. Our main results for pure strategies are as follows:
    (1) For one-sided games with player 2 having perfect 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 almost-sure 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 and present symbolic algorithms that avoid the
    explicit exponential construction. (2) For one-sided games with player 1 having
    perfect observation we show that nonelementarymemory 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 nonelementary 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 exhibit serious
    flaws in previous results of the literature: we show a nonelementary memory lower
    bound for almost-sure winning whereas an exponential upper bound was previously
    claimed.@eng'
  bibo_authorlist:
  - foaf_Person:
      foaf_givenName: Krishnendu
      foaf_name: Chatterjee, Krishnendu
      foaf_surname: Chatterjee
      foaf_workInfoHomepage: http://www.librecat.org/personId=2E5DCA20-F248-11E8-B48F-1D18A9856A87
    orcid: 0000-0002-4561-241X
  - foaf_Person:
      foaf_givenName: Laurent
      foaf_name: Doyen, Laurent
      foaf_surname: Doyen
  bibo_doi: 10.1145/2579821
  bibo_issue: '2'
  bibo_volume: 15
  dct_date: 2014^xs_gYear
  dct_identifier:
  - UT:000336005000006
  dct_language: eng
  dct_publisher: ACM@
  dct_title: 'Partial-observation stochastic games: How to win when belief fails@'
...