# HW 08: Moderation and Stratification

Identifing different trends within subgroups

# Purpose

To start to motivate multiple regression, we need to explore how a third variable can muck up the relationship between a predictor and an outcome variable. This assignment will have you testing prior analyses for potential moderators.

# Instructions

- For each type of analysis (ANOVA, \(\chi^2\), Regression), decide on a third variable to test as a moderating variable.
- The potential moderator can be different for each analyses. You need to decide what variables are most appropriate for your research question.
- This third variable must be categorical and the fewer number of levels it has the easier it is to interpret.

- Adjust your bivariate visualization to account for this third variable (see ASCN Ch 2.7 for guidance and code).
- Typical methods for plotting a third variable include paneling or coloring by the third variable.
- State your thoughts about how the relationship between the explanatory and response variable has
*changed*with levels of the moderator variable.

- Adjust your analysis hypothesis to include this third variable.
- Is the relationship between X and Y the same for all levels of Z?

- For each analysis, run the original model, and stratified model.

- Determine if the third variable is a moderator or not and justify your answer.

See ASCN Ch 8.6 for a templated example.

# Submission instructions

- Download this [QMD] file and use it to write your answers in.
- Right click and ‘save as’, put this in your
`scripts`

folder.

- Right click and ‘save as’, put this in your
- Render to pdf and upload your final PDF to Canvas by the due date.