no code implementations • ICML 2020 • Kangrui Wang, Oliver Hamelijnck, Theodoros Damoulas, Mark Steel
We describe a framework for constructing non-separable non-stationary random fields that is based on an infinite mixture of convolved stochastic processes.
no code implementations • 25 Nov 2024 • Charita Dellaporta, Patrick O'Hara, Theodoros Damoulas
Decision making under uncertainty is challenging as the data-generating process (DGP) is often unknown.
1 code implementation • 9 Oct 2024 • Ioannis Zachos, Mark Girolami, Theodoros Damoulas
Agent-based models (ABMs) are proliferating as decision-making tools across policy areas in transportation, economics, and epidemiology.
no code implementations • 20 Sep 2024 • Oliver Hamelijnck, Arno Solin, Theodoros Damoulas
Differential equations are important mechanistic models that are integral to many scientific and engineering applications.
no code implementations • 5 Sep 2024 • Charita Dellaporta, Patrick O'Hara, Theodoros Damoulas
Decision making under uncertainty is challenging since the data-generating process (DGP) is often unknown.
1 code implementation • 26 Apr 2024 • Fabio Massimo Zennaro, Nicholas Bishop, Joel Dyer, Yorgos Felekis, Anisoara Calinescu, Michael Wooldridge, Theodoros Damoulas
Multi-armed bandits (MAB) and causal MABs (CMAB) are established frameworks for decision-making problems.
no code implementations • 18 Dec 2023 • Joel Dyer, Nicholas Bishop, Yorgos Felekis, Fabio Massimo Zennaro, Anisoara Calinescu, Theodoros Damoulas, Michael Wooldridge
Agent-based simulators provide granular representations of complex intelligent systems by directly modelling the interactions of the system's constituent agents.
1 code implementation • 13 Dec 2023 • Yorgos Felekis, Fabio Massimo Zennaro, Nicola Branchini, Theodoros Damoulas
Causal abstraction (CA) theory establishes formal criteria for relating multiple structural causal models (SCMs) at different levels of granularity by defining maps between them.
no code implementations • 2 Jun 2023 • Charita Dellaporta, Theodoros Damoulas
This approach gives rise to a general framework that is suitable for both Classical and Berkson error models via the appropriate specification of the prior centering measure of a Dirichlet Process (DP).
1 code implementation • 7 May 2023 • Fabio Massimo Zennaro, Paolo Turrini, Theodoros Damoulas
However, switching between different levels of abstraction requires evaluating a trade-off between the consistency and the information loss among different models.
1 code implementation • 14 Jan 2023 • Fabio Massimo Zennaro, Máté Drávucz, Geanina Apachitei, W. Dhammika Widanage, Theodoros Damoulas
An abstraction can be used to relate two structural causal models representing the same system at different levels of resolution.
no code implementations • 23 Aug 2022 • Nicola Branchini, Virginia Aglietti, Neil Dhir, Theodoros Damoulas
We study the problem of globally optimizing the causal effect on a target variable of an unknown causal graph in which interventions can be performed.
1 code implementation • 1 Aug 2022 • Fabio Massimo Zennaro, Paolo Turrini, Theodoros Damoulas
Working with causal models at different levels of abstraction is an important feature of science.
1 code implementation • 9 Feb 2022 • Charita Dellaporta, Jeremias Knoblauch, Theodoros Damoulas, François-Xavier Briol
Simulator-based models are models for which the likelihood is intractable but simulation of synthetic data is possible.
no code implementations • 22 Jan 2022 • Joel Jaskari, Jaakko Sahlsten, Theodoros Damoulas, Jeremias Knoblauch, Simo Särkkä, Leo Kärkkäinen, Kustaa Hietala, Kimmo Kaski
Automatic classification of diabetic retinopathy from retinal images has been widely studied using deep neural networks with impressive results.
1 code implementation • NeurIPS 2021 • Oliver Hamelijnck, William J. Wilkinson, Niki A. Loppi, Arno Solin, Theodoros Damoulas
We introduce a scalable approach to Gaussian process inference that combines spatio-temporal filtering with natural gradient variational inference, resulting in a non-conjugate GP method for multivariate data that scales linearly with respect to time.
1 code implementation • NeurIPS 2021 • Virginia Aglietti, Neil Dhir, Javier González, Theodoros Damoulas
This paper studies the problem of performing a sequence of optimal interventions in a causal dynamical system where both the target variable of interest and the inputs evolve over time.
1 code implementation • NeurIPS 2021 • Cristopher Salvi, Maud Lemercier, Chong Liu, Blanka Hovarth, Theodoros Damoulas, Terry Lyons
Stochastic processes are random variables with values in some space of paths.
no code implementations • 5 Aug 2021 • Shanaka Perera, Virginia Aglietti, Theodoros Damoulas
We demonstrate how BSIM outperforms competing approaches on this large dataset in terms of prediction performances while providing results that are both interpretable and consistent with related indicators observed for the London region.
no code implementations • 10 May 2021 • Maud Lemercier, Cristopher Salvi, Thomas Cass, Edwin V. Bonilla, Theodoros Damoulas, Terry Lyons
Making predictions and quantifying their uncertainty when the input data is sequential is a fundamental learning challenge, recently attracting increasing attention.
no code implementations • 8 Dec 2020 • Chance Haycock, Edward Thorpe-Woods, James Walsh, Patrick O'Hara, Oscar Giles, Neil Dhir, Theodoros Damoulas
One of the Greater London Authority's (GLA) response to the COVID-19 pandemic brings together multiple large-scale and heterogeneous datasets capturing mobility, transportation and traffic activity over the city of London to better understand 'busyness' and enable targeted interventions and effective policy-making.
no code implementations • 7 Dec 2020 • James Walsh, Oluwafunmilola Kesa, Andrew Wang, Mihai Ilas, Patrick O'Hara, Oscar Giles, Neil Dhir, Mark Girolami, Theodoros Damoulas
During the COVID-19 pandemic, policy makers at the Greater London Authority, the regional governance body of London, UK, are reliant upon prompt and accurate data sources.
no code implementations • NeurIPS 2020 • Ayman Boustati, Omer Deniz Akyildiz, Theodoros Damoulas, Adam Johansen
We introduce a framework for inference in general state-space hidden Markov models (HMMs) under likelihood misspecification.
1 code implementation • 3 Nov 2020 • Juan Maroñas, Oliver Hamelijnck, Jeremias Knoblauch, Theodoros Damoulas
Gaussian Processes (GPs) can be used as flexible, non-parametric function priors.
1 code implementation • NeurIPS 2020 • Virginia Aglietti, Theodoros Damoulas, Mauricio Álvarez, Javier González
This paper studies the problem of learning the correlation structure of a set of intervention functions defined on the directed acyclic graph (DAG) of a causal model.
no code implementations • 24 Aug 2020 • David J. Armstrong, Jevgenij Gamper, Theodoros Damoulas
Over 30% of the ~4000 known exoplanets to date have been discovered using 'validation', where the statistical likelihood of a transit arising from a false positive (FP), non-planetary scenario is calculated.
no code implementations • 28 Jun 2020 • Daniel J. Tait, Theodoros Damoulas
Specifying a governing physical model in the presence of missing physics and recovering its parameters are two intertwined and fundamental problems in science.
no code implementations • 10 Jun 2020 • Maud Lemercier, Cristopher Salvi, Theodoros Damoulas, Edwin V. Bonilla, Terry Lyons
In this paper, we develop a rigorous mathematical framework for distribution regression where inputs are complex data streams.
no code implementations • 23 Feb 2020 • Ayman Boustati, Ömer Deniz Akyildiz, Theodoros Damoulas, Adam M. Johansen
We introduce a framework for inference in general state-space hidden Markov models (HMMs) under likelihood misspecification.
1 code implementation • 9 Oct 2019 • Ömer Deniz Akyildiz, Gerrit J. J. van den Burg, Theodoros Damoulas, Mark F. J. Steel
In particular, we consider nonlinear Gaussian state-space models where sequential approximate inference results in the factorization of a data matrix into a dictionary and time-varying coefficients with potentially nonlinear Markovian dependencies.
Multivariate Time Series Forecasting Multivariate Time Series Imputation +2
no code implementations • 4 Oct 2019 • Ying Zhang, Ömer Deniz Akyildiz, Theodoros Damoulas, Sotirios Sabanis
In this paper, we are concerned with a non-asymptotic analysis of sampling algorithms used in nonconvex optimization.
1 code implementation • NeurIPS 2019 • Oliver Hamelijnck, Theodoros Damoulas, Kangrui Wang, Mark Girolami
We consider evidence integration from potentially dependent observation processes under varying spatio-temporal sampling resolutions and noise levels.
no code implementations • 18 Jun 2019 • Patrick O'Hara, M. S. Ramanujan, Theodoros Damoulas
CLT is related to the family of Travelling Salesman Problems with Profits, but differs by defining the weight function on edges instead of vertices, and by requiring the total weight to be within a range instead of being at least some quota.
1 code implementation • NeurIPS 2019 • Virginia Aglietti, Edwin V. Bonilla, Theodoros Damoulas, Sally Cripps
We propose a scalable framework for inference in an inhomogeneous Poisson process modeled by a continuous sigmoidal Cox process that assumes the corresponding intensity function is given by a Gaussian process (GP) prior transformed with a scaled logistic sigmoid function.
no code implementations • 29 May 2019 • Ayman Boustati, Theodoros Damoulas, Richard S. Savage
We present a multi-task learning formulation for Deep Gaussian processes (DGPs), through non-linear mixtures of latent processes.
1 code implementation • 3 Apr 2019 • Jeremias Knoblauch, Jack Jewson, Theodoros Damoulas
We advocate an optimization-centric view on and introduce a novel generalization of Bayesian inference.
no code implementations • NeurIPS 2018 • Jeremias Knoblauch, Jack E. Jewson, Theodoros Damoulas
The resulting inference procedure is doubly robust for both the predictive and the changepoint (CP) posterior, with linear time and constant space complexity.
1 code implementation • NeurIPS 2018 • Jeremias Knoblauch, Jack Jewson, Theodoros Damoulas
The resulting inference procedure is doubly robust for both the parameter and the changepoint (CP) posterior, with linear time and constant space complexity.
1 code implementation • 24 May 2018 • Virginia Aglietti, Theodoros Damoulas, Edwin Bonilla
We generalize the log Gaussian Cox process (LGCP) framework to model multiple correlated point data jointly.
1 code implementation • ICML 2018 • Jeremias Knoblauch, Theodoros Damoulas
Bayesian On-line Changepoint Detection is extended to on-line model selection and non-stationary spatio-temporal processes.