Table of Contents
Fetching ...

Structural Parameterizations of the Biclique-Free Vertex Deletion Problem

Lito Goldmann, Leon Kellerhals, Tomohiro Koana

TL;DR

This work shows that Biclique-Free Vertex Deletion is fixed-parameter tractable with respect to k + d for the degeneracy and has a polynomial kernel for every $i \ge 1$ when parameterized by the feedback edge number.

Abstract

In this work, we study the Biclique-Free Vertex Deletion problem: Given a graph $G$ and integers $k$ and $i \le j$, find a set of at most $k$ vertices that intersects every (not necessarily induced) biclique $K_{i, j}$ in $G$. This is a natural generalization of the Bounded-Degree Deletion problem, wherein one asks whether there is a set of at most $k$ vertices whose deletion results in a graph of a given maximum degree $r$. The two problems coincide when $i = 1$ and $j = r + 1$. We show that Biclique-Free Vertex Deletion is fixed-parameter tractable with respect to $k + d$ for the degeneracy $d$ by developing a $2^{O(d k^2)} \cdot n^{O(1)}$-time algorithm. We also show that it can be solved in $2^{O(f k)} \cdot n^{O(1)}$ time for the feedback vertex number $f$ when $i \ge 2$. In contrast, we find that it is W[1]-hard for the treedepth for any integer $i \ge 1$. Finally, we show that Biclique-Free Vertex Deletion has a polynomial kernel for every $i \ge 1$ when parameterized by the feedback edge number. Previously, for this parameter, its fixed-parameter tractability for $i = 1$ was known (Betzler et al., 2012) but the existence of polynomial kernel was open.

Structural Parameterizations of the Biclique-Free Vertex Deletion Problem

TL;DR

This work shows that Biclique-Free Vertex Deletion is fixed-parameter tractable with respect to k + d for the degeneracy and has a polynomial kernel for every when parameterized by the feedback edge number.

Abstract

In this work, we study the Biclique-Free Vertex Deletion problem: Given a graph and integers and , find a set of at most vertices that intersects every (not necessarily induced) biclique in . This is a natural generalization of the Bounded-Degree Deletion problem, wherein one asks whether there is a set of at most vertices whose deletion results in a graph of a given maximum degree . The two problems coincide when and . We show that Biclique-Free Vertex Deletion is fixed-parameter tractable with respect to for the degeneracy by developing a -time algorithm. We also show that it can be solved in time for the feedback vertex number when . In contrast, we find that it is W[1]-hard for the treedepth for any integer . Finally, we show that Biclique-Free Vertex Deletion has a polynomial kernel for every when parameterized by the feedback edge number. Previously, for this parameter, its fixed-parameter tractability for was known (Betzler et al., 2012) but the existence of polynomial kernel was open.
Paper Structure (14 sections, 23 theorems, 4 equations, 1 figure, 1 algorithm)

This paper contains 14 sections, 23 theorems, 4 equations, 1 figure, 1 algorithm.

Key Result

Lemma 1

If rr:part_of_a_biclique has been applied exhaustively, then $\bigcup_{S \in \mathcal{S}_G} S$ is a vertex cover of $G$.

Figures (1)

  • Figure 1: A Hasse diagram of parameters we study in this paper. An edge from $x$ (left) to $y$ (right) indicates that $x(G) \ge y(G) - 1$ for every graph $G$.

Theorems & Definitions (40)

  • Lemma 1
  • Proposition 2
  • proof
  • Proposition 3
  • proof
  • Lemma 4: DBLP:journals/algorithmica/AlonG09
  • Lemma 5
  • proof
  • Lemma 6
  • proof
  • ...and 30 more