summary: logical; if TRUE returns summary statistic instead of all MCMC samples
transform: a transformation (R function) to apply to the result; (this is commonly used when calling from other plotting or printing functions)
interval: uncertainty interval width (numeric between 0 and 1), if summary=TRUE
Returns
A list with 2 vectors (corresponding to MCMC samples) tau (mean effect) and sigma_tau (SD). If summary=TRUE, both vectors are summarised as mean and lower/upper bounds according to interval
See Also
treatment_effect for overall treatment effect across groups, group_effects for effects within each group, effect_draw and effect_plot for predicted treatment effect in new group