Search Results for author: Ilya Shpitser

Found 45 papers, 7 papers with code

Evaluation of Active Feature Acquisition Methods for Static Feature Settings

no code implementations6 Dec 2023 Henrik von Kleist, Alireza Zamanian, Ilya Shpitser, Narges Ahmidi

These estimators can be applied when the missingness in the retrospective dataset follows a missing-at-random (MAR) pattern.

Offline RL reinforcement-learning +1

Evaluation of Active Feature Acquisition Methods for Time-varying Feature Settings

no code implementations3 Dec 2023 Henrik von Kleist, Alireza Zamanian, Ilya Shpitser, Narges Ahmidi

We show that one can apply offline reinforcement learning under the NUC assumption and missing data methods under the NDE assumption.

reinforcement-learning

Identification and Estimation for Nonignorable Missing Data: A Data Fusion Approach

no code implementations15 Nov 2023 Zixiao Wang, AmirEmad Ghassami, Ilya Shpitser

We consider the task of identifying and estimating a parameter of interest in settings where data is missing not at random (MNAR).

When does the ID algorithm fail?

no code implementations7 Jul 2023 Ilya Shpitser

The ID algorithm is sound (outputs the correct functional of the observed data distribution whenever p(Y | do(a)) is identified in the causal model represented by the input graph), and complete (explicitly flags as a failure any input p(Y | do(a)) whenever this distribution is not identified in the causal model represented by the input graph).

Partial Identification of Causal Effects Using Proxy Variables

no code implementations10 Apr 2023 AmirEmad Ghassami, Ilya Shpitser, Eric Tchetgen Tchetgen

However, completeness is well-known not to be empirically testable, and although a bridge function may be well-defined, lack of completeness, sometimes manifested by availability of a single type of proxy, may severely limit prospects for identification of a bridge function and thus a causal effect; therefore, potentially restricting the application of the proximal causal framework.

Causal Inference

Causal Discovery in Linear Latent Variable Models Subject to Measurement Error

1 code implementation8 Nov 2022 Yuqin Yang, AmirEmad Ghassami, Mohamed Nafea, Negar Kiyavash, Kun Zhang, Ilya Shpitser

We demonstrate a somewhat surprising connection between this problem and causal discovery in the presence of unobserved parentless causes, in the sense that there is a mapping, given by the mixing matrix, between the underlying models to be inferred in these problems.

Causal Discovery

Causal and counterfactual views of missing data models

no code implementations11 Oct 2022 Razieh Nabi, Rohit Bhattacharya, Ilya Shpitser, James Robins

It is often said that the fundamental problem of causal inference is a missing data problem -- the comparison of responses to two hypothetical treatment assignments is made difficult because for every experimental unit only one potential response is observed.

Causal Identification Causal Inference +1

Combining Experimental and Observational Data for Identification and Estimation of Long-Term Causal Effects

no code implementations26 Jan 2022 AmirEmad Ghassami, Alan Yang, David Richardson, Ilya Shpitser, Eric Tchetgen Tchetgen

We consider the task of identifying and estimating the causal effect of a treatment variable on a long-term outcome variable using data from an observational domain and an experimental domain.

Causal Inference

A Systematic Review of Robustness in Deep Learning for Computer Vision: Mind the gap?

no code implementations1 Dec 2021 Nathan Drenkow, Numair Sani, Ilya Shpitser, Mathias Unberath

We find this area of research has received disproportionately less attention relative to adversarial machine learning, yet a significant robustness gap exists that manifests in performance degradation similar in magnitude to adversarial conditions.

Adversarial Robustness Data Augmentation +1

Causal Inference with Hidden Mediators

1 code implementation4 Nov 2021 AmirEmad Ghassami, Alan Yang, Ilya Shpitser, Eric Tchetgen Tchetgen

In this paper, we extend the proximal causal inference approach to settings where identification of causal effects hinges upon a set of mediators which are not observed, yet error prone proxies of the hidden mediators are measured.

Causal Inference

Partially Intervenable Causal Models

no code implementations24 Oct 2021 AmirEmad Ghassami, Ilya Shpitser

We give a complete identification theory for such models, and develop a complete calculus of interventions based on a generalization of the do-calculus, and axioms that govern probabilistic operations on Markov kernels.

Causal Inference

An Automated Approach to Causal Inference in Discrete Settings

no code implementations28 Sep 2021 Guilherme Duarte, Noam Finkelstein, Dean Knox, Jonathan Mummolo, Ilya Shpitser

When causal quantities cannot be point identified, researchers often pursue partial identification to quantify the range of possible values.

Causal Inference

The Proximal ID Algorithm

no code implementations15 Aug 2021 Ilya Shpitser, Zach Wood-Doughty, Eric J. Tchetgen Tchetgen

Unobserved confounding is a fundamental obstacle to establishing valid causal conclusions from observational data.

Causal Inference valid

Entropic Inequality Constraints from $e$-separation Relations in Directed Acyclic Graphs with Hidden Variables

no code implementations15 Jul 2021 Noam Finkelstein, Beata Zjawin, Elie Wolfe, Ilya Shpitser, Robert W. Spekkens

Directed acyclic graphs (DAGs) with hidden variables are often used to characterize causal relations between variables in a system.

Multiply Robust Causal Mediation Analysis with Continuous Treatments

no code implementations19 May 2021 Numair Sani, Yizhen Xu, AmirEmad Ghassami, Ilya Shpitser

For binary treatments, efficient estimators for the direct and indirect effects are presented in Tchetgen Tchetgen and Shpitser (2012) based on the influence function of the parameter of interest.

Minimax Kernel Machine Learning for a Class of Doubly Robust Functionals with Application to Proximal Causal Inference

1 code implementation7 Apr 2021 AmirEmad Ghassami, Andrew Ying, Ilya Shpitser, Eric Tchetgen Tchetgen

In this paper, we first extend the class of Robins et al. to include doubly robust IFs in which the nuisance functions are solutions to integral equations.

BIG-bench Machine Learning Causal Inference +1

Generating Synthetic Text Data to Evaluate Causal Inference Methods

no code implementations10 Feb 2021 Zach Wood-Doughty, Ilya Shpitser, Mark Dredze

High-dimensional and unstructured data such as natural language complicates the evaluation of causal inference methods; such evaluations rely on synthetic datasets with known causal effects.

Causal Inference Text Generation

Partial Identifiability in Discrete Data With Measurement Error

no code implementations23 Dec 2020 Noam Finkelstein, Roy Adams, Suchi Saria, Ilya Shpitser

When data contains measurement errors, it is necessary to make assumptions relating the observed, erroneous data to the unobserved true phenomena of interest.

counterfactual

Differentiable Causal Discovery Under Unmeasured Confounding

1 code implementation14 Oct 2020 Rohit Bhattacharya, Tushar Nagarajan, Daniel Malinsky, Ilya Shpitser

In this work, we derive differentiable algebraic constraints that fully characterize the space of ancestral ADMGs, as well as more general classes of ADMGs, arid ADMGs and bow-free ADMGs, that capture all equality restrictions on the observed variables.

Causal Discovery

Path Dependent Structural Equation Models

no code implementations24 Aug 2020 Ranjani Srinivasan, Jaron Lee, Rohit Bhattacharya, Narges Ahmidi, Ilya Shpitser

Causal analyses of longitudinal data generally assume that the qualitative causal structure relating variables remains invariant over time.

Causal Inference

Multivariate Counterfactual Systems And Causal Graphical Models

no code implementations13 Aug 2020 Ilya Shpitser, Thomas S. Richardson, James M. Robins

Among Judea Pearl's many contributions to Causality and Statistics, the graphical d-separation} criterion, the do-calculus and the mediation formula stand out.

Methodology 62P10

Deriving Bounds and Inequality Constraints Using LogicalRelations Among Counterfactuals

no code implementations1 Jul 2020 Noam Finkelstein, Ilya Shpitser

We additionally provide inequality constraints on functionals of the observed data law implied by such causal models.

counterfactual

A Semiparametric Approach to Interpretable Machine Learning

no code implementations8 Jun 2020 Numair Sani, Jaron Lee, Razieh Nabi, Ilya Shpitser

In order to combat this shortcoming, we propose a novel approach to trading off interpretability and performance in prediction models using ideas from semiparametric statistics, allowing us to combine the interpretability of parametric regression models with performance of nonparametric methods.

BIG-bench Machine Learning Decision Making +2

Explaining the Behavior of Black-Box Prediction Algorithms with Causal Learning

no code implementations3 Jun 2020 Numair Sani, Daniel Malinsky, Ilya Shpitser

However, existing approaches have two important shortcomings: (i) the "explanatory units" are micro-level inputs into the relevant prediction model, e. g., image pixels, rather than interpretable macro-level features that are more useful for understanding how to possibly change the algorithm's behavior, and (ii) existing approaches assume there exists no unmeasured confounding between features and target model predictions, which fails to hold when the explanatory units are macro-level variables.

counterfactual

Full Law Identification In Graphical Models Of Missing Data: Completeness Results

no code implementations ICML 2020 Razieh Nabi, Rohit Bhattacharya, Ilya Shpitser

Missing data has the potential to affect analyses conducted in all fields of scientific study, including healthcare, economics, and the social sciences.

General Identification of Dynamic Treatment Regimes Under Interference

no code implementations2 Apr 2020 Eli Sherman, David Arbour, Ilya Shpitser

In many applied fields, researchers are often interested in tailoring treatments to unit-level characteristics in order to optimize an outcome of interest.

Identification Methods With Arbitrary Interventional Distributions as Inputs

no code implementations2 Apr 2020 Jaron J. R. Lee, Ilya Shpitser

This entails using \emph{identification theory} to establish a link between counterfactual parameters of interest and distributions from which data is available.

Causal Inference counterfactual

Semiparametric Inference For Causal Effects In Graphical Models With Hidden Variables

no code implementations27 Mar 2020 Rohit Bhattacharya, Razieh Nabi, Ilya Shpitser

We derive influence function based estimators that exhibit double robustness for the identified effects in a large class of hidden variable DAGs where the treatment satisfies a simple graphical criterion; this class includes models yielding the adjustment and front-door functionals as special cases.

Counterexamples to "The Blessings of Multiple Causes" by Wang and Blei

no code implementations17 Jan 2020 Elizabeth L. Ogburn, Ilya Shpitser, Eric J. Tchetgen Tchetgen

This note has been updated (April, 2020) to respond to "Towards Clarifying the Theory of the Deconfounder" by Yixin Wang, David M. Blei (arXiv:2003. 04948).

Comment on "Blessings of Multiple Causes"

no code implementations11 Oct 2019 Elizabeth L. Ogburn, Ilya Shpitser, Eric J. Tchetgen Tchetgen

(This comment has been updated to respond to Wang and Blei's rejoinder [arXiv:1910. 07320].)

Causal Inference valid

Optimal Training of Fair Predictive Models

no code implementations9 Oct 2019 Razieh Nabi, Daniel Malinsky, Ilya Shpitser

Specifically, we show how to reparameterize the observed data likelihood such that fairness constraints correspond directly to parameters that appear in the likelihood, transforming a complex constrained optimization objective into a simple optimization problem with box constraints.

Fairness

Identification In Missing Data Models Represented By Directed Acyclic Graphs

no code implementations29 Jun 2019 Rohit Bhattacharya, Razieh Nabi, Ilya Shpitser, James M. Robins

Missing data is a pervasive problem in data analyses, resulting in datasets that contain censored realizations of a target distribution.

Causal Inference

Causal Inference Under Interference And Network Uncertainty

no code implementations29 Jun 2019 Rohit Bhattacharya, Daniel Malinsky, Ilya Shpitser

Classical causal and statistical inference methods typically assume the observed data consists of independent realizations.

Causal Inference

Conditionally-additive-noise Models for Structure Learning

no code implementations20 May 2019 Daniel Chicharro, Stefano Panzeri, Ilya Shpitser

Methods based on additive-noise (AN) models have been proposed to further discriminate between causal structures that are equivalent in terms of conditional independencies.

regression

Causal inference, social networks, and chain graphs

3 code implementations12 Dec 2018 Elizabeth L. Ogburn, Ilya Shpitser, Youjin Lee

Traditionally, statistical and causal inference on human subjects relies on the assumption that individuals are independently affected by treatments or exposures.

Methodology

Identification and Estimation of Causal Effects from Dependent Data

no code implementations NeurIPS 2018 Eli Sherman, Ilya Shpitser

The assumption that data samples are independent and identically distributed (iid) is standard in many areas of statistics and machine learning.

Causal Inference

Challenges of Using Text Classifiers for Causal Inference

1 code implementation EMNLP 2018 Zach Wood-Doughty, Ilya Shpitser, Mark Dredze

Causal understanding is essential for many kinds of decision-making, but causal inference from observational data has typically only been applied to structured, low-dimensional datasets.

Causal Inference Decision Making

Estimation of Personalized Effects Associated With Causal Pathways

no code implementations27 Sep 2018 Razieh Nabi, Phyllis Kanki, Ilya Shpitser

For example, we may wish to maximize the chemical effect of a drug given data from an observational study where the chemical effect of the drug on the outcome is entangled with the indirect effect mediated by differential adherence.

counterfactual Decision Making

Learning Optimal Fair Policies

no code implementations6 Sep 2018 Razieh Nabi, Daniel Malinsky, Ilya Shpitser

Systematic discriminatory biases present in our society influence the way data is collected and stored, the way variables are defined, and the way scientific findings are put into practice as policy.

Causal Inference Decision Making +1

Fair Inference On Outcomes

no code implementations29 May 2017 Razieh Nabi, Ilya Shpitser

We discuss a number of complications that arise in classical statistical inference due to this view and provide workarounds based on recent work in causal and semi-parametric inference.

Fairness

Consistent Estimation of Functions of Data Missing Non-Monotonically and Not at Random

no code implementations NeurIPS 2016 Ilya Shpitser

Our estimators, which are generalized inverse probability weighting estimators, make no assumptions on the underlying full data law, but instead place independence restrictions, and certain other fairly mild assumptions, on the distribution of missingness status conditional on the data.

Segregated Graphs and Marginals of Chain Graph Models

no code implementations NeurIPS 2015 Ilya Shpitser

Our results suggest that segregated graphs define an analogue of the ordinary Markov model for marginals of chain graph models.

Sparse Nested Markov models with Log-linear Parameters

no code implementations26 Sep 2013 Ilya Shpitser, Robin J. Evans, Thomas S. Richardson, James M. Robins

To make modeling and inference with nested Markov models practical, it is necessary to limit the number of parameters in the model, while still correctly capturing the constraints in the marginal of a DAG model.

Causal Inference

On the definition of a confounder

no code implementations2 Apr 2013 Tyler J. VanderWeele, Ilya Shpitser

The literature has not, however, come to any consensus on a formal definition of a confounder, as it has given priority to the concept of confounding over that of a confounder.

Causal Inference counterfactual +1

What Counterfactuals Can Be Tested

1 code implementation20 Jun 2012 Ilya Shpitser, Judea Pearl

Counterfactual statements, e. g., "my headache would be gone had I taken an aspirin" are central to scientific discourse, and are formally interpreted as statements derived from "alternative worlds".

counterfactual

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