By Chenyan Jia
install.packages("mediation")
library(mediation)
<code>results <- mediate(model.mediator = mod3, model.y = mod2, treat='exercise', mediator='food', boot=TRUE, sims=500)</code>
results <- mediate(model.mediator = mod3, model.y = mod2, treat='exercise', mediator='food', boot=TRUE, sims=500) # "model.mediator": a fitted model object for mediator. # "model.y": a fitted model object for outcome (using both the focal and mediator variables) # "treat" a character string indicating the name of the treatment variable # "mediator": a character string indicating the name of the mediator variable # Typically bootstrap sample size ranges between 1000 ~ 5000. Remember, only use small simulations because our data are small. How to decipher the results? ## ACME: Average Causal Mediation Effects ## ADE: Average Direct Effects ## Total Effect: Sum of a mediation (indirect) effect and a direct effect ## Prop. Mediated: Size of the average causal mediation effects relative to the total effect. ## When ACME is significant and ADE is not significant, a complete mediation happens (Direct effects are not significant any more because of the mediator )
An Example of Results
