There is a research model with one IV, one DV and one mediator. So, when checking the parametric assumptions in SPSS, what will be done to the mediator?

Does the following answer is true?

Path 1: IV to Mediator

For the path where the IV predicts the mediator, the mediator is treated as the outcome.

• Run a simple regression with the IV as the predictor and the mediator as the dependent variable. Check parametric assumptions for this regression:
  • Linearity
  • Normality of Residuals
  • Homoscedasticity
  • Independence of Errors

Path 2: Mediator to DV (and IV to DV)

In this step, the mediator serves as a predictor of the DV, alongside the IV.

• Run a regression with the IV and the mediator as predictors and the DV as the outcome. Check assumptions for this second regression model:
  • Linearity
  • Normality of Residuals
  • Homoscedasticity
  • Independence of Errors
  • Multicollinearity