An Improved Algorithm for Online Min-Sum Set Cover

نویسندگان

چکیده

We study a fundamental model of online preference aggregation, where an algorithm maintains ordered list n elements. An input is stream preferred sets R_1, R_2, ..., R_t, ... Upon seeing R_t and without knowledge any future sets, has to rerank elements (change the ordering), so that at least one element found near front. The incurred cost sum update costs (the number swaps neighboring elements) access position first on list). This scenario occurs naturally in applications such as ordering items shop using aggregated preferences customers. theoretical underpinning this problem known Min-Sum Set Cover. Unlike previous work mostly studied performance ALG comparison static optimal solution (a single paper, we arguably harder variant benchmark provably stronger dynamic OPT (that may also modify ordering). In terms shop, means its user base evolve with time. construct computationally efficient randomized whose competitive ratio (ALG-to-OPT ratio) O(r^2) prove existence deterministic O(r^4)-competitive algorithm. Here, r maximum cardinality R_t. does not depend n: previously best for was O(r^(3/2) * n^(1/2))-competitive Ω(r) lower bound

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Improved Approximation for Min-Sum Vertex Cover

The paper describes an approximation algorithm for the Min Sum Vertex Cover (MSVC) problem, achieving a constant approximation factor strictly smaller than 2, thus improving on the best currently known approximation algorithm for the problem. ∗Department of Computer Science and Applied Mathematics, The Weizmann Institute of Science, Rehovot 76100, Israel. E-mail: [email protected]. †Depar...

متن کامل

Min-Sum Set Cover and Its Generalizations

Min Sum Set Cover and its Generalizations Name: Sungjin Im Affil./Addr. Electrical Engineering and Computer Science, University of California, Merced, CA, USA

متن کامل

A note on the generalized min-sum set cover problem

In this paper, we consider the generalized min-sum set cover problem, introduced by Azar, Gamzu, and Yin [1]. Bansal, Gupta, and Krishnaswamy [2] give a 485approximation algorithm for the problem. We are able to alter their algorithm and analysis to obtain a 28-approximation algorithm, improving the performance guarantee by an order of magnitude. We use concepts from α-point scheduling to obtai...

متن کامل

Preemptive and Non-Preemptive Generalized Min Sum Set Cover

In the (non-preemptive) Generalized Min Sum Set Cover Problem, we are given n ground elements and a collection of sets S = {S1, S2, ..., Sm} where each set Si ∈ 2 has a positive requirement κ(Si) that has to be fulfilled. We would like to order all elements to minimize the total (weighted) cover time of all sets. The cover time of a set Si is defined as the first index j in the ordering such th...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Proceedings of the ... AAAI Conference on Artificial Intelligence

سال: 2023

ISSN: ['2159-5399', '2374-3468']

DOI: https://doi.org/10.1609/aaai.v37i6.25835