add_index is a generic function that adds a (moderated) indirect effect index to an object created with an mdt_* family function. This index is computed using Monte Carlo methods. This function invokes particular methods depending of the class of the mediation model. For example, with a model fitted with mdt_simple, add_index will invoke add_index.simple_mediation.

add_index(mediation_model, times = 5000, level = 0.05, ...)



A mediation model fitted with an mdt_* family function.


Number of simulations to use to compute the Monte Carlo index's confidence interval.


Alpha threshold to use for the confidence interval.


Further arguments to be passed to specific methods.


An object of the same class as mediation_model, but with index added for later use.