کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
439232 690470 2008 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A randomized competitive algorithm for evaluating priced AND/OR trees
موضوعات مرتبط
مهندسی و علوم پایه مهندسی کامپیوتر نظریه محاسباتی و ریاضیات
پیش نمایش صفحه اول مقاله
A randomized competitive algorithm for evaluating priced AND/OR trees
چکیده انگلیسی

Recently, Charikar et al. investigated the problem of evaluating AND/OR trees, with non-uniform costs on its leaves, from the perspective of the competitive analysis. For an AND/OR tree T they presented a μ(T)-competitive deterministic polynomial time algorithm, where μ(T) is the number of leaves that must be read, in the worst case, in order to determine the value of T. Furthermore, they proved that μ(T) is a lower bound on the deterministic competitiveness, which assures the optimality of their algorithm.The power of randomization in this context has remained as an open question. Here, we take a step towards solving this problem by presenting a -competitive randomized polynomial time algorithm. This contrasts with the best known lower bound μ(T)/2.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Theoretical Computer Science - Volume 401, Issues 1–3, 23 July 2008, Pages 120-130