TY - RPRT AU - Ahrens, Achim AU - Hansen, Christian B. AU - Schaffer, Mark E AU - Wiemann, Thomas TI - ddml: Double/Debiased Machine Learning in Stata PY - 2023/Feb/ PB - Institute of Labor Economics (IZA) CY - Bonn T2 - IZA Discussion Paper IS - 15963 UR - https://www.iza.org/publications/dp15963 AB - We introduce the package ddml for Double/Debiased Machine Learning (DDML) in Stata. Estimators of causal parameters for five different econometric models are supported, allowing for flexible estimation of causal effects of endogenous variables in settings with unknown functional forms and/or many exogenous variables. ddml is compatible with many existing supervised machine learning programs in Stata. We recommend using DDML in combination with stacking estimation which combines multiple machine learners into a final predictor. We provide Monte Carlo evidence to support our recommendation. KW - doubly-robust estimation KW - machine learning KW - causal inference KW - st0001 ER -