Proceedings 41st Annual Symposium on Foundations of Computer Science最新文献

Existential second-order logic over graphs: charting the tractability frontier 图上的存在二阶逻辑:绘制可追踪边界

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892334

Georg Gottlob, Ph. G. Kolaitis, T. Schwentick

{"title":"Existential second-order logic over graphs: charting the tractability frontier","authors":"Georg Gottlob, Ph. G. Kolaitis, T. Schwentick","doi":"10.1109/SFCS.2000.892334","DOIUrl":"https://doi.org/10.1109/SFCS.2000.892334","url":null,"abstract":"Fagin's (1974) theorem, the first important result of descriptive complexity, asserts that a property of graphs is in NP if and only if it is definable by an existential second-order formula. We study the complexity of evaluating existential second-order formulas that belong to prefix classes of existential second-order logic, where a prefix class is the collection of all existential second-order and the first-order quantifiers obey a certain quantifier pattern. We completely characterize the computation complexity of prefix classes of existential second-order logic in three different contexts: over directed graphs; over undirected graphs with self-loops; and over undirected graphs without self-loops. Our main result is that in each of these three contexts a dichotomy holds, i.e., each prefix class of existential second-order logic either contains sentences that can express NP-complete problems or each of its sentences expresses a polynomial-time solvable problem. Although the boundary of the dichotomy coincides for the first two cases, it changes, as one move to undirected graphs without self-loops.","PeriodicalId":216082,"journal":{"name":"Proceedings 41st Annual Symposium on Foundations of Computer Science","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123232015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 35

Optimization problems in congestion control 拥塞控制中的优化问题

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892066

R. Karp, E. Koutsoupias, C. Papadimitriou, S. Shenker

引用次数: 84

Nearly optimal expected-case planar point location 几乎最优的期望情况平面点位置

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892108

S. Arya, Theocharis Malamatos, D. Mount

{"title":"Nearly optimal expected-case planar point location","authors":"S. Arya, Theocharis Malamatos, D. Mount","doi":"10.1109/SFCS.2000.892108","DOIUrl":"https://doi.org/10.1109/SFCS.2000.892108","url":null,"abstract":"We consider the planar point location problem from the perspective of expected search time. We are given a planar polygonal subdivision S and for each polygon of the subdivision the probability that a query point lies within this polygon. The goal is to compute a search structure to determine which cell of the subdivision contains a given query point, so as to minimize the expected search time. This is a generalization of the classical problem of computing an optimal binary search tree for one-dimensional keys. In the one-dimensional case it has long been known that the entropy H of the distribution is the dominant term in the lower bound on the expected-case search time, and further there exist search trees achieving expected search times of at most H+2. Prior to this work, there has been no known structure for planar point location with an expected search time better than 2H, and this result required strong assumptions on the nature of the query point distribution. Here we present a data structure whose expected search time is nearly equal to the entropy lower bound, namely H+o(H). The result holds for any polygonal subdivision in which the number of sides of each of the polygonal cells is bounded, and there are no assumptions on the query distribution within each cell. We extend these results to subdivisions with convex cells, assuming a uniform query distribution within each cell.","PeriodicalId":216082,"journal":{"name":"Proceedings 41st Annual Symposium on Foundations of Computer Science","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116048746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

The product replacement algorithm is polynomial 产品替换算法是多项式的

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892135

I. Pak

引用次数: 58

Using expander graphs to find vertex connectivity 使用扩展图查找顶点连通性

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892129

H. Gabow

引用次数: 66

Detecting a network failure 检测网络故障

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892110

J. Kleinberg

{"title":"Detecting a network failure","authors":"J. Kleinberg","doi":"10.1109/SFCS.2000.892110","DOIUrl":"https://doi.org/10.1109/SFCS.2000.892110","url":null,"abstract":"Measuring the properties of a large, unstructured network can be difficult: one may not have full knowledge of the network topology, and detailed global measurements may be infeasible. A valuable approach to such problems is to take measurements from selected locations within the network and then aggregate them to infer large-scale properties. One sees this notion applied in settings that range from Internet topology discovery tools to remote software agents that estimate the download times of popular Web pages. Some of the most basic questions about this type of approach, however, are largely unresolved at an analytical level. How reliable are the results? How much does the choice of measurement locations affect the aggregate information one infers about the network? We describe algorithms that yield provable guarantees for a particular problem of this type: detecting a network failure. Suppose we want to detect events of the following form: an adversary destroys up to k nodes or edges, after which two subsets of the nodes, each at least an /spl epsi/ fraction of the network, are disconnected from one another. We call such an event an (/spl epsi/,k) partition. One method for detecting such events would be to place \"agents\" at a set D of nodes, and record a fault whenever two of them become separated from each other. To be a good detection set, D should become disconnected whenever there is an (/spl epsi/,k)-partition; in this way, it \"witnesses\" all such events. We show that every graph has a detection set of size polynomial in k and /spl epsi//sup -1/, and independent of the size of the graph itself. Moreover, random sampling provides an effective way to construct such a set. Our analysis establishes a connection between graph separators and the notion of VC-dimension, using techniques based on matchings and disjoint paths.","PeriodicalId":216082,"journal":{"name":"Proceedings 41st Annual Symposium on Foundations of Computer Science","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124564490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 68

Efficient algorithms for universal portfolios 通用投资组合的有效算法

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892136

A. Kalai, S. Vempala

引用次数: 172

On the boundary complexity of the union of fat triangles 胖三角形并集的边界复杂度

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892130

J. Pach, G. Tardos

引用次数: 35

Approximability and in-approximability results for no-wait shop scheduling 无等待车间调度的逼近性和非逼近性结果

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892071

M. Sviridenko, G. Woeginger

引用次数: 7

Using upper confidence bounds for online learning 使用上置信度限在线学习

Proceedings 41st Annual Symposium on Foundations of Computer Science Pub Date : 2000-11-12 DOI: 10.1109/SFCS.2000.892116

P. Auer

引用次数: 49