1. You are given the following variables age (scale), blood pressure (scale), sex (nominal), degree level (ordinal). Using some (not all) of these variables, create an example of one independent variable – one dependent variable research question and two independent variables one dependent variable research question. This second one should have both independent variables impacting the same dependent variable.
2. Why is a between-groups variance explainable and a within-group variance unexplainable?
3. Why is knowledge of within-group variance in each group necessary to make a decision about reliable differences between two groups mean performances?