DoWhy — Causal Inference DoWhy answers the question every analyst actually wants answered: "Does X cause Y, or is it just correlated?" Correlation is everywhere. Causation requires structure — a causal graph that encodes which variables influence which. DoWhy's workflow is three steps: Identify (is the effect estimable from this graph?) → Estimate (compute the effect) → Refute (is this estimate robust?). Core Mental Model When to Use - "Does this ad campaign actually increase sales, or do people who see ads already buy more?" - "Does smoking cause cancer?" (observational data, can't randomize…