Search Results for author: James Worrell

Found 6 papers, 0 papers with code

When are Local Queries Useful for Robust Learning?

no code implementations12 Oct 2022 Pascale Gourdeau, Varun Kanade, Marta Kwiatkowska, James Worrell

We finish by giving robust learning algorithms for halfspaces on $\{0, 1\}^n$ and then obtaining robustness guarantees for halfspaces in $\mathbb{R}^n$ against precision-bounded adversaries.

Sample Complexity Bounds for Robustly Learning Decision Lists against Evasion Attacks

no code implementations12 May 2022 Pascale Gourdeau, Varun Kanade, Marta Kwiatkowska, James Worrell

A fundamental problem in adversarial machine learning is to quantify how much training data is needed in the presence of evasion attacks.

PAC learning

On the Hardness of Robust Classification

no code implementations NeurIPS 2019 Pascale Gourdeau, Varun Kanade, Marta Kwiatkowska, James Worrell

However if the adversary is restricted to perturbing $O(\log n)$ bits, then the class of monotone conjunctions can be robustly learned with respect to a general class of distributions (that includes the uniform distribution).

Classification General Classification +2

On Restricted Nonnegative Matrix Factorization

no code implementations23 May 2016 Dmitry Chistikov, Stefan Kiefer, Ines Marušić, Mahsa Shirmohammadi, James Worrell

Nonnegative matrix factorization (NMF) is the problem of decomposing a given nonnegative $n \times m$ matrix $M$ into a product of a nonnegative $n \times d$ matrix $W$ and a nonnegative $d \times m$ matrix $H$.

Nonnegative Matrix Factorization Requires Irrationality

no code implementations22 May 2016 Dmitry Chistikov, Stefan Kiefer, Ines Marušić, Mahsa Shirmohammadi, James Worrell

Nonnegative matrix factorization (NMF) is the problem of decomposing a given nonnegative $n \times m$ matrix $M$ into a product of a nonnegative $n \times d$ matrix $W$ and a nonnegative $d \times m$ matrix $H$.

Open-Ended Question Answering

Complexity of Equivalence and Learning for Multiplicity Tree Automata

no code implementations2 May 2014 Ines Marusic, James Worrell

Habrard and Oncina (2006) give an exact learning algorithm for multiplicity tree automata, in which the number of queries is proportional to the size of the target automaton and the size of a largest counterexample, represented as a tree, that is returned by the Teacher.

Cannot find the paper you are looking for? You can Submit a new open access paper.