ria.test - Testing Equality of Natural Mediation Effects and Their
Randomized Interventional Analogues
Implements the empirical test introduced by Yu, Ge, and
Elwert (2026) for detecting when randomized interventional
analogues should not be interpreted as natural mediation
effects. The package estimates natural effects, their
randomized interventional analogues, and TE - TE^R, the
difference between the total effect and its randomized
interventional analogue. Rejecting TE - TE^R = 0 falsifies the
composite null that the natural indirect and direct effects
equal their randomized interventional analogues. The procedure
remains valid in settings where the natural effects themselves
are not identified, and |TE - TE^R| provides a lower bound on
the total divergence between the natural and randomized
interventional decompositions. The package is built on
'crumble', authored by Nicholas Williams, Richard Liu, and Iván
Díaz.
