Alternative Measures of Direct and Indirect Effects

There are a number of measures of direct and indirect effects in the literature on causality. These are suitable in some cases and unsuitable in others. We describe a case where the existing measures are unsuitable and propose new suitable ones. We also show that the new measures can partially handle unmeasured treatment-outcome confounding, and bound long-term effects by combining experimental and observational data. We also introduce the concepts of indirect benefit and harm (i.e., through a mediator), and use our new measure to quantify them.