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Alexander Marx

10 accepted papers

2024

Exploiting Causal Graph Priors with Posterior Sampling for Reinforcement Learning

ICLR 2024poster

Posterior sampling allows exploitation of prior knowledge on the environment's transition dynamics to improve the sample efficiency of reinforcement learning. The prior is typically specified as a class of parametric distributions, the design of which can be cumbersome in practice, often resulting i…

Cited by 5SourcePDFScholar
2023

Beyond Normal: On the Evaluation of Mutual Information Estimators

NeurIPS 2023poster

Mutual information is a general statistical dependency measure which has found applications in representation learning, causality, domain generalization and computational biology. However, mutual information estimators are typically evaluated on simple families of probability distributions, namely m…

2023

Effective Bayesian Heteroscedastic Regression with Deep Neural Networks

NeurIPS 2023poster

Flexibly quantifying both irreducible aleatoric and model-dependent epistemic uncertainties plays an important role for complex regression problems. While deep neural networks in principle can provide this flexibility and learn heteroscedastic aleatoric uncertainties through non-linear functions, re…

2023

Identifiability Results for Multimodal Contrastive Learning

ICLR 2023poster

Contrastive learning is a cornerstone underlying recent progress in multi-view and multimodal learning, e.g., in representation learning with image/caption pairs. While its effectiveness is not yet fully understood, a line of recent work reveals that contrastive learning can invert the data generati…

2023

On the Identifiability and Estimation of Causal Location-Scale Noise Models

ICML 2023poster

We study the class of location-scale or heteroscedastic noise models (LSNMs), in which the effect $Y$ can be written as a function of the cause $X$ and a noise source $N$ independent of $X$, which may be scaled by a positive function $g$ over the cause, i.e., $Y = f(X) + g(X)N$. Despite the generali…

2022

Inferring Cause and Effect in the Presence of Heteroscedastic Noise

ICML 2022spotlight

We study the problem of identifying cause and effect over two univariate continuous variables $X$ and $Y$ from a sample of their joint distribution. Our focus lies on the setting when the variance of the noise may be dependent on the cause. We propose to partition the domain of the cause into multip…

Cited by 23SourcePDFScholar
2019

Testing Conditional Independence on Discrete Data using Stochastic Complexity

AISTATS 2019poster

Testing for conditional independence is a core aspect of constraint-based causal discovery. Although commonly used tests are perfect in theory, they often fail to reject independence in practice—especially when conditioning on multiple variables. We focus on discrete data and propose a new test bas…

Cited by 37SourcePDFScholar