collaborators

7 papers

cs.DS2026

On the Parameterized Complexity of Min-Sum-Radii

Pankaj Kumar, Haiko Müller, Sebastian Ordyniak +1

In the Min-Sum-Radii (MSR) clustering problem, we are given a finite set X of n points in a metric space. The objective is to find at most k clusters centered at a subset of these…

cs.CC2026

Clausal Deletion Backdoors for QBF: a Parameterized Complexity Approach

Leif Eriksson, Victor Lagerkvist, Sebastian Ordyniak +3

Determining the validity of a quantified Boolean formula (QBF) is a PSPACE-complete problem with rich expressive power. Despite interest in efficient solvers, there is, compared to…

cs.DS2026

Backdoors for Quantified Boolean Formulas

Leif Eriksson, Victor Lagerkvist, Sebastian Ordyniak +3

The quantified Boolean formula problem (QBF) is a well-known PSpace-complete problem with rich expressive power, and is generally viewed as the SAT analogue for PSpace. Given that…

cs.DS2026

Optimal FPT-Approximability for Modular Linear Equations

Konrad K. Dabrowski, Peter Jonsson, Sebastian Ordyniak +2

We show optimal FPT-approximability results for solving almost satisfiable systems of modular linear equations, completing the picture of the parameterized complexity and FPT-appro…

cs.AI2025

Explaining Decisions in ML Models: a Parameterized Complexity Analysis (Part I)

Sebastian Ordyniak, Giacomo Paesani, Mateusz Rychlicki +1

This paper presents a comprehensive theoretical investigation into the parameterized complexity of explanation problems in various machine learning (ML) models. Contrary to the pre…

cs.DS2025

Parameterized Approximability for Modular Linear Equations

Konrad K. Dabrowski, Peter Jonsson, Sebastian Ordyniak +2

We consider the Min--Lin problem: given a system of length- linear equations modulo , find of minimum cardinality such that is satisfiable…