Research Scenario: A developmental psychologist is studying whether attachment can be improved upon by providing a parent training course. He has 10 parents who are seeking services to improve their children's attachment to them. He uses a measure of which higher scores indicate more secure attachments to caregivers and gave it to them before and after the 4 week parent training course. The attachment scores data are presented below for Before and After the parent training course. Assume the data are normally distributed. Did the parent training course improve attachment?

Before After

14 15

15 16

17 17

11 15

12 11

16 16

13 17

10 11

13 14

15 15

Answer the following questions based on the provided scenario.

Use the output to calculate r² (show your work in the space provided and remember if a number is negative, when squaring it will lose its sign and be positive). Interpret it (small, medium, large) based on the conventions for this effect size calculation.