Hayes Process Macro - Model 4 - Mediation Analysis
Hayes Process Model - Lecture Series
The tutorial will guide on Model 4 of the Hayes Process Macro for Mediation Analysis.
Introduction
- Up to this point, we have focused on how to perform moderation analysis using the Process Macro.
- Let’s now examine how the influence between two constructs may take an indirect path through a third variable called a mediator.
- In these situations, the third variable will intervene on the influence of the two constructs (Hair et al. 2009).
- In testing if “mediation” or the presence of a mediator in a model, you need to understand some of the terminology that is used, such as direct effect, indirect effect, and total effects.
A direct effect is simply a direct relationship between an independent variable and a dependent variable in presence of the Mediator (c’).
An indirect effect is the relationship that flows from an independent variable to a mediator and then to a dependent variable (a*b).
The term total effect is the combined influence of the direct effect between two constructs and the indirect effect flowing through the mediator (c = c’ + a*b).
- c in the relationship between X and Y is the total effect.
Example
- We want to examine if the construct of Culture has an indirect effect through Commitment on the construct of Organizational Performance.
Conceptual and Statistical Diagram
- Example Variables: 1 predictor X, 1 Mediator M, and 1 Outcome Y
- The variables are continuous
How to Run
- Step 1: Analyze -> Regression -> Process v4.0 by Andrew F. Hayes
- Step 2: Put in the Required Variables. In this case,
- Y Variable (Dependent Variable) is OP
- X Variable (Independent Variable) is Culture
- Mediator is Commitment
- Model Number is 4
- Step 3: Select Option Button, and Choose the options as shown in the figure below ()
- Select Show total effect model (only models 4,6,70,81, 82), this is to generate total effect estimates.
- For Standardized effect, select Standardized effects (mediation-only models).
- Press Continue
Output Interpretation - Basic Summary
- Description of Model along with the different variables where Y is Dependent Variable, X is Independent Variable, and M is the Mediating Variable.
Output Interpretation - Model Summary
- Model Summary, provides summary of the model with R, R-Sq, F Statistics, and P value for the overall model.
- Next, is the coefficients, with impact of Culture on Commitment
- Culture has a significant impact on Commitment. This is path a.
Output Interpretation - Outcome and Total Effect Model
- Following figure shows the antecedent for the outcome of OP
- Culture has a significant impact on OP (b = 0.2917, t = 5.5426, p < 0.001). Here this is Direct effect (c’).
- Commitment was also found to have a significant impact on OP (b = 0.4530, t = 8.5392, p < 0.001). This is path b.
- Next, total effect is presented.
- Indirect Effect is calculated by multiplying a and b. Indirect effect = a (0.6041) * b (0.4531) = 0.2736
- Direct Effect = 0.2917, this is the effect of Culture on Performance in presence of the mediator (c’)
- Total effect is the sum of direct and indirect effect. Total Effect = 0.5653
Output Interpretation - Type and Form of Mediation
- Is there a Mediation: Yes
Indirect Effect is Significant.
- Is it Full or Partial
Partial, Since both Total and Direct Effects are Significant.
- Is it Complementary or Competitive
- a*b*c’ (If Positive: Complimentary)
- a*b*c’ (If Negative: Competitive)
- Complimentary. The Sign of Direct and Indirect Effect is same.
How to Interpret Hayes Process Output - Reporting Mediation Analysis
Mediation Analysis
H1: Commitment mediates the relationship between Collaborative Culture and Organizational Performance
The study assessed the mediating role of Commitment on the relationship between Collaborative Culture and Organizational Performance. The results revealed a significant indirect effect of impact of Collaborative Culture on organizational performance (b= 0.273, t = 5.583), supporting H1. Furthermore, the direct effect of collaborative culture on organizational performance in presence of the mediator was also found significant (b = 0.291, p < 0.001). Hence, commitment partially mediated the relationship between collaborative culture and organizational performance. Mediation analysis summary is presented in Table 1.
