Replication Data for: Post hoc, propter hoc? Counterfactuals, placebos and spillovers in evaluating a local mobility policy

Policy reforms are often unique, in the sense that it is hard to find comparable changes and circumstances that would make it possible to clearly identify their net consequences and thus unambiguously support causality attributions. Without the appropriate counterfactuals, there is no way scholars can avoid the uncertainty of their estimates. However, we should accept the causal complexity that characterizes social science, give up on the idea of a model’s precision, and increase the robustness of our empirical evidence through multiple testing. This is the research strategy that we adopted in evaluating a reform in the mobility policy of the municipality of Milan, in Italy, that cannot be easily compared to other policy changes. We found overall evidence of the direct and indirect effects of the policy reform, but the research design helped us refining some of our original expectations and fine-tuning the underlying mechanism. This methodological research journey uses the proposed case study to advocate for redundancy in the direct and indirect empirical evidence needed to evaluate any policy change.