Identifying Counterfactual Queries with the R Package cfid

TL;DR

This paper introduces the R package cfid, which implements algorithms for identifying counterfactual queries within causal models, aiding fairness and decision-making analysis.

Contribution

The paper presents the cfid package that implements the ID* and IDC* algorithms for counterfactual identification in causal models, expanding tools for causal inference in R.

Findings

Implemented ID* and IDC* algorithms in R package cfid.

Demonstrated counterfactual query identification with examples.

Facilitated causal inference for fairness and decision-making.

Abstract

In the framework of structural causal models, counterfactual queries describe events that concern multiple alternative states of the system under study. Counterfactual queries often take the form of "what if" type questions such as "would an applicant have been hired if they had over 10 years of experience, when in reality they only had 5 years of experience?" Such questions and counterfactual inference in general are crucial, for example when addressing the problem of fairness in decision-making. Because counterfactual events contain contradictory states of the world, it is impossible to conduct a randomized experiment to address them without making several restrictive assumptions. However, it is sometimes possible to identify such queries from observational and experimental data by representing the system under study as a causal model, and the available data as symbolic probability distributions. Shpitser and Pearl (2007) constructed two algorithms, called ID* and IDC*, for identifying counterfactual queries and conditional counterfactual queries, respectively. These two algorithms are analogous to the ID and IDC algorithms by Shpitser and Pearl (2006) for identification of interventional distributions, which were implemented in R by Tikka and Karvanen (2017) in the causaleffect package. We present the R package cfid that implements the ID* and IDC* algorithms. Identification of counterfactual queries and the features of cfid are demonstrated via examples.