Correlational Design and Correlation Coefficient

Question 1

Correlational Design

Answer 1

Allows us to describe the relation between two or more variables.

Question 2

When to use it?

Answer 2

• cant manipulate variables (eg. depression)
• examining relation among many variables
• when making predictions
• examine reliability and validity of measures

Question 3

Pearson Correlation Coefficient (r)

Effect Size

Answer 3

Direction of relation: positive or negative
Strength of relation: strongest closest to 1.00 (0 is no relation).
Meaningfulness/ importance of an effect
.10 = small
.20 = medium
.50 = large

Question 4

Scatterplots

Answer 4

Indicate the relation of variables through scatters.