StaggeredDifferenceInDifferences.plot_tau_surface#
- StaggeredDifferenceInDifferences.plot_tau_surface(hdi_prob=0.94)[source]#
Plot the ETWFE effect surface, one panel per adoption cohort.
The aggregated event study collapses every cohort into a single line, which is exactly the information that the extended two-way fixed effects parametrisation exists to preserve. This figure puts each cohort’s
tau[g, k]profile in its own panel, so cohort heterogeneity – effects that grow faster for later adopters, say – is visible directly.- Parameters:
hdi_prob (
float) – Probability mass for the credible band on the Bayesian path. Defaults tocausalpy.constants.HDI_PROB. Ignored on the OLS path, which draws a 95% normal-approximation interval from the coefficient standard errors.- Returns:
The figure and one axis per cohort, in cohort order.
- Return type:
- Raises:
ValueError – If the experiment was run with
estimator="imputation", which produces notau_surface_.