An introduction to Causal Modelling

TL;DR

This tutorial offers a comprehensive introduction to modern causal modeling, integrating potential outcomes and graphical methods, with practical examples for applied researchers.

Contribution

It combines potential outcomes and graphical approaches in causal modeling, providing clear explanations and practical guidance for researchers.

Findings

Introduction of causal effect measures like average treatment effects

Extension of identification methods to stratification and blocking

Explanation of graphical criteria such as d-separation and backdoor

Abstract

This tutorial provides a concise introduction to modern causal modeling by integrating potential outcomes and graphical methods. We motivate causal questions such as counterfactual reasoning under interventions and define binary treatments and potential outcomes. We discuss causal effect measures-including average treatment effects on the treated and on the untreated-and choices of effect scales for binary outcomes. We derive identification in randomized experiments under exchangeability and consistency, and extend to stratification and blocking designs. We present inverse probability weighting with propensity score estimation and robust inference via sandwich estimators. Finally, we introduce causal graphs, d-separation, the backdoor criterion, single-world intervention graphs, and structural equation models, showing how graphical and potential-outcome approaches complement each other. Emphasis is placed on clear notation, intuitive explanations, and practical examples for applied researchers.