2 Search Results for "Redivo-Zaglia, Michela"


Document
Track B: Automata, Logic, Semantics, and Theory of Programming
Integer Linear-Exponential Programming in NP by Quantifier Elimination

Authors: Dmitry Chistikov, Alessio Mansutti, and Mikhail R. Starchak

Published in: LIPIcs, Volume 297, 51st International Colloquium on Automata, Languages, and Programming (ICALP 2024)


Abstract
This paper provides an NP procedure that decides whether a linear-exponential system of constraints has an integer solution. Linear-exponential systems extend standard integer linear programs with exponential terms 2^x and remainder terms (x mod 2^y). Our result implies that the existential theory of the structure (ℕ,0,1,+,2^(⋅),V_2(⋅,⋅), ≤) has an NP-complete satisfiability problem, thus improving upon a recent EXPSPACE upper bound. This theory extends the existential fragment of Presburger arithmetic with the exponentiation function x ↦ 2^x and the binary predicate V_2(x,y) that is true whenever y ≥ 1 is the largest power of 2 dividing x. Our procedure for solving linear-exponential systems uses the method of quantifier elimination. As a by-product, we modify the classical Gaussian variable elimination into a non-deterministic polynomial-time procedure for integer linear programming (or: existential Presburger arithmetic).

Cite as

Dmitry Chistikov, Alessio Mansutti, and Mikhail R. Starchak. Integer Linear-Exponential Programming in NP by Quantifier Elimination. In 51st International Colloquium on Automata, Languages, and Programming (ICALP 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 297, pp. 132:1-132:20, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


Copy BibTex To Clipboard

@InProceedings{chistikov_et_al:LIPIcs.ICALP.2024.132,
  author =	{Chistikov, Dmitry and Mansutti, Alessio and Starchak, Mikhail R.},
  title =	{{Integer Linear-Exponential Programming in NP by Quantifier Elimination}},
  booktitle =	{51st International Colloquium on Automata, Languages, and Programming (ICALP 2024)},
  pages =	{132:1--132:20},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-322-5},
  ISSN =	{1868-8969},
  year =	{2024},
  volume =	{297},
  editor =	{Bringmann, Karl and Grohe, Martin and Puppis, Gabriele and Svensson, Ola},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ICALP.2024.132},
  URN =		{urn:nbn:de:0030-drops-202758},
  doi =		{10.4230/LIPIcs.ICALP.2024.132},
  annote =	{Keywords: decision procedures, integer programming, quantifier elimination}
}
Document
Extrapolation and minimization procedures for the PageRank vector

Authors: Claude Brezinski and Michela Redivo-Zaglia

Published in: Dagstuhl Seminar Proceedings, Volume 7071, Web Information Retrieval and Linear Algebra Algorithms (2007)


Abstract
An important problem in Web search is to determine the importance of each page. This problem consists in computing, by the power method, the left principal eigenvector (the PageRank vector) of a matrix depending on a parameter $c$ which has to be chosen close to 1. However, when $c$ is close to 1, the problem is ill-conditioned, and the power method converges slowly. So, the idea developed in this paper consists in computing the PageRank vector for several values of $c$, and then to extrapolate them, by a conveniently chosen rational function, at a point near 1. The choice of this extrapolating function is based on the mathematical considerations about the PageRank vector.

Cite as

Claude Brezinski and Michela Redivo-Zaglia. Extrapolation and minimization procedures for the PageRank vector. In Web Information Retrieval and Linear Algebra Algorithms. Dagstuhl Seminar Proceedings, Volume 7071, pp. 1-6, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2007)


Copy BibTex To Clipboard

@InProceedings{brezinski_et_al:DagSemProc.07071.9,
  author =	{Brezinski, Claude and Redivo-Zaglia, Michela},
  title =	{{Extrapolation and minimization procedures for the PageRank vector}},
  booktitle =	{Web Information Retrieval and Linear Algebra Algorithms},
  pages =	{1--6},
  series =	{Dagstuhl Seminar Proceedings (DagSemProc)},
  ISSN =	{1862-4405},
  year =	{2007},
  volume =	{7071},
  editor =	{Andreas Frommer and Michael W. Mahoney and Daniel B. Szyld},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/DagSemProc.07071.9},
  URN =		{urn:nbn:de:0030-drops-10682},
  doi =		{10.4230/DagSemProc.07071.9},
  annote =	{Keywords: Extrapolation, PageRank, Web matrix, eigenvector computation.}
}
  • Refine by Author
  • 1 Brezinski, Claude
  • 1 Chistikov, Dmitry
  • 1 Mansutti, Alessio
  • 1 Redivo-Zaglia, Michela
  • 1 Starchak, Mikhail R.

  • Refine by Classification
  • 1 Computing methodologies → Symbolic and algebraic algorithms
  • 1 Theory of computation → Logic

  • Refine by Keyword
  • 1 Extrapolation
  • 1 PageRank
  • 1 Web matrix
  • 1 decision procedures
  • 1 eigenvector computation.
  • Show More...

  • Refine by Type
  • 2 document

  • Refine by Publication Year
  • 1 2007
  • 1 2024