It is becoming increasingly popular in applications of synthetic control methods to include the entire pre-treatment path of the outcome variable as economic predictors. We demonstrate both theoretically and empirically that using all outcome lags as separate predictors renders all other...

We examine the impact of the EUR 5 billion German Cash-for-Clunkers program on vehicle registrations and respective CO2 emissions. To construct proper counterfactuals, we develop the multivariate synthetic control method using time series of economic predictors (MSCMT) and show (asymptotic)...

While the literature on synthetic control methods mostly abstracts from out-of-sample measures, Abadie et al. (2015) have recently introduced a cross-validation approach. This technique, however, is not well-defined since it hinges on predictor weights which are not uniquely defined. We fix this...