To complete this unit you need to
- Watch the video lectures
- Read the materials for the written assignment 3 (optional)
- Complete the unit 4 discussion forum task
- Return written assignment 3 (optional)
- View the model answer for written assignment 3 and instructors comment's to written assignment 3 (optional)
- Participate in the seminar (optional)
- Participate in the computer class (optional)
- Submit data analysis assignment 2 (optional)
The unit continues from the previous unit with additional issues in linear regression models, focusing on common applications of the technique: mediation and moderation. We will also introduce instrumental variables. After this unit you should:
- Understand the concepts of mediation and moderation models and why this kind of models are useful for research.
- Know how interaction terms can be used in regression to estimate moderation models.
- Understand why plotting is useful and marginal effects are essential for interpreting mediation model results and know why centering of variables will be useless and even counterproductive in proper interpretation of mediation models.
- Know the two most common strategies for estimating mediation models: the Baron and Kenny causal steps approach and the simultaneous equations approach.
- Have a basic understanding of what instrumental variables, how they can be applied to test and control for endogeneity, and how instrumental variables can be used in two-stage least squares estimation. You should be aware of the instrument relevance criterion and the instrument exclusion criterion.