Fourth Barcelona-Ulm Workshop on Probabilistic Complexity Classes and Nonuniform Computational Models: Barcelona, 13-17 September, 1993

 

Proceedings of the 4th Barcelona-Ulm Workshop on Probabilistic Complexity Classes and Nonuniform Computational Models

Barcelona, September 13-17, 1993

Organized by:

  • Universitat Politècnica de Catalunya. Departament de Llenguatges i Sistemes Informàtics
  • Universität Ulm

[Publicat originalment com a Report de recerca LSI/93/24/R]

Summary

  • Bounded queries to arbitrary sets 

    Lozano Boixadors, Antoni (1993)
    Conference report
    Open Access
    We prove that if P^(A [k])= P^(A [k+1]) for some k and an arbitrary set A, then A is reducible to its complement under a relativized nondeterministic conjunctive reduction. This result shows the first known property of ...

  • The Ø-operator and the low hierarchy 

    Castro Rabal, Jorge; Seara Ojea, Carlos (1993)
    Conference report
    Open Access
    Long and Sheu in their paper [LS-91] introduced a refinement of the low hierarchy based on the Θ-levels of the polynomial time hierarchy which gives a deeper sight of the internal structure of N P. In this paper we show ...

  • On dlogtime and polylogtime reductions 

    Álvarez Faura, M. del Carme; Jenner Núñez, Birgit (1993)
    Conference report
    Open Access
    We investigate properties of the relativized NC and AC hierarchies in their DLOGTIME-. respectively, ALOGTIME-uniform setting and show that these hierarchies can be characterized in terms of adaptive reducibility in ...

  • On the learnability of output-DFA: a proof and an implementation 

    Domingo, Carlos; Guijarro, David (1993)
    Conference report
    Open Access
    This paper presents an algorithm that learns Output-DFA by making Evaluation and Equivalence queries. The correctness and termination of the algorithm are discussed. A description of the implementation of the algorithm ...

  • ALMOST-R: characterizations using different concepts of randomness 

    Book, Ronald V.; Mayordomo, Elvira (1993)
    Conference report
    Open Access
    We study here the classes of the form ALMOST-R, for R a reducibility. This includes among other the classes BPP, P and PH. We give a characterization of this classes in terms of reducibility to n-random languages, a ...

  • The structure of a logarithmic advice class 

    Hermo, Montserrat (1993)
    Conference report
    Open Access
    The complexity class Full-P / log, corresponding to a form of logarithmic advice for polynomial time, is studied. In order to understand the inner structure of this class, we characterize Full-P /log in terms of Turing ...

  • Separation of two-query-adaptive from two-query-non-adaptive completeness if NP is not small 

    Mayordomo, Elvira (1993)
    Conference report
    Open Access
    Under the hypothesis that NP does not have p-measure O (roughly, that NP contains more than a negligible subset of exponential time), it is shown that there is a language that is ≤ P/2-T complete but not ≤ P/2-tt complete ...

  • Sequential and parallel complexity of learning DFA 

    Balcázar Navarro, José Luis; Díaz Cort, Josep; Gavaldà, Ricard (1993)
    Conference report
    Open Access
    It is known that the class of deterministic finite automata is polynomial time learnable by using membership and equivalence queries. We investigate the query complexity of learning deterministic finite automata, i.e., ...

  • On sets bounded truth-table reducible to P-selective sets 

    Thierauf, Thomas; Toda, Seinosuke; Watanabe, Osamu (1993)
    Conference report
    Open Access
    We show that if every NP set is ≤ P btt -reducible to some P-selective set, then NP is contained in DTIME(2nO(1/logn√)). The result is extended for some unbounded reducibilities such as ≤ P polylog-tt -reducibility.

  • Sparse sets, simplicity, and lowness 

    Mundhenk, Martin (1993)
    Conference report
    Open Access

  • On average case complexity 

    Schuler, Rainer (1993)
    Conference report
    Open Access
    The airn of this talk is to give an introduction to the notion of Levin's average case complexity and then show sorne of the fields were recent research in this area is focused on. The first part is motivated by the ...