activity
20242026
collaborators

5 papers

cs.AI2026

Transformer Heads Looking for Order

Jasper van Doornmalen, Alexander Kozachinskiy, Corinna Mathwieser +4

In this note, we show that the problem of checking, whether a sequence of bits is ordered, is not doable by 1-head 1-layer transformers but is doable by a 2-head 1-layer transforme…

stat.ML2026

Tight Sample Complexity for Low-Degree and Sparse Boolean Polynomials

Jasper van Doornmalen, Mathieu Molina, Victor Verdugo +1

Motivated by the optimization of bounded binary black-box functions, we study the problem of learning polynomial surrogates over the Boolean hypercube. To ensure that optimizing th…

cs.LG2025

Explaining k-Nearest Neighbors: Abductive and Counterfactual Explanations

Pablo Barceló, Alexander Kozachinskiy, Miguel Romero Orth +2

Despite the wide use of -Nearest Neighbors as classification models, their explainability properties remain poorly understood from a theoretical perspective. While nearest neigh…

cs.DS2024

Randomized Binary and Tree Search under Pressure

Agustín Caracci, Christoph Dürr, José Verschae

We study a generalized binary search problem on the line and general trees. On the line (e.g., a sorted array), binary search finds a target node in queries in the wors…

cs.DS2024

Set Selection with Uncertain Weights: Non-Adaptive Queries and Thresholds

Christoph Dürr, Arturo Merino, José A. Soto +1

We study set selection problems where the weights are uncertain. Instead of its exact weight, only an uncertainty interval containing its true weight is available for each element.…