Calculate mediation effect size from total and direct effects, or run a Sobel test to find indirect effect, z-value, p-value, CI, and percent mediated.
Mediation Effect Size Formula
The following formula is used to calculate the mediation effect size.
ab = c - c'
Variables:
- ab is the mediation effect size
- c is the total effect of the independent variable on the dependent variable
- c' is the direct effect of the independent variable on the dependent variable after accounting for the mediator
To calculate the mediation effect size, subtract the direct effect (c') from the total effect (c).
What is Mediation Effect Size?
Mediation effect size represents the indirect effect of an independent variable on a dependent variable through a mediator variable. It is a key concept in mediation analysis, which is used to understand how and why certain effects occur. The mediation effect size helps in quantifying the proportion of the total effect that is mediated.
How to Calculate Mediation Effect Size?
The following steps outline how to calculate the Mediation Effect Size.
- First, determine the total effect (c) of the independent variable on the dependent variable.
- Next, determine the direct effect (c') of the independent variable on the dependent variable after accounting for the mediator.
- Use the formula to calculate the mediation effect size (ab) = c - c'.
- Finally, calculate the Mediation Effect Size (ab).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
Total effect (c) = 0.5
Direct effect (c') = 0.3
