1. The same statistical procedure (t-test for dependent samples) is used for both the matched-pairs t-test and the repeated-measured t-test. Are there differences in how degrees of freedom are calculated for matched pairs versus repeated measures designs?

2. Are non-parametric statistical procedures as powerful as parametric statistical procedures?

3. Describe why is it advisable to generate a scatterplot before computing a correlation coefficient between two variables?

4.Describe the relation between scales of measurement and measures of variability (e.g., interquartile range and standard deviation.)