no code implementations • 2 Oct 2024 • Sammy Khalife, Josué Tonelli-Cueto
Uniform expressivity guarantees that a Graph Neural Network (GNN) can express a query without the parameters depending on the size of the input graphs.
no code implementations • 13 Feb 2024 • Sammy Khalife, Yann Ponty, Laurent Bulteau
For a window of size at least 3, we prove hardness of all variants, even when w is considered as a constant, with the notable exception of the undirected/unweighted case for which we propose an XP algorithms for both (realizability and enumeration) problems, tight due to a corresponding W[1]-hardness result.
no code implementations • 4 Feb 2024 • Hongyu Cheng, Sammy Khalife, Barbara Fiedorowicz, Amitabh Basu
We build upon recent work in this line of research by considering the setup where, instead of selecting a single algorithm that has the best performance, we allow the possibility of selecting an algorithm based on the instance to be solved, using neural networks.
no code implementations • 19 Oct 2023 • Sammy Khalife
In this article, we prove that some GC2 queries of depth $3$ cannot be expressed by GNNs with any rational activation function.
no code implementations • 10 Jul 2023 • Sammy Khalife, Amitabh Basu
In contrast, it was already known that unbounded GNNs (those whose size is allowed to change with the graph sizes) with piecewise polynomial activations can distinguish these vertices in only two iterations.
no code implementations • 15 Nov 2021 • Sammy Khalife, Hongyu Cheng, Amitabh Basu
We precisely characterize the class of functions that are representable by such neural networks and show that 2 hidden layers are necessary and sufficient to represent any function representable in the class.
no code implementations • WS 2019 • Sammy Khalife, Michalis Vazirgiannis
In this paper, we consider the named entity linking (NEL) problem.