A psychologist conducts a correlational study to investigate the relationship between night-time sleep duration (in hours) and daytime cognitive processing speed (measured in milliseconds).
After analyzing the data, they calculate both Pearson's correlation coefficient (rrr) and the coefficient of determination (r2r^2r2). Which of the following pairs of calculated values is mathematically possible?
r=−0.50r = -0.50r=−0.50 and r2=−0.25r^2 = -0.25r2=−0.25
r=−0.90r = -0.90r=−0.90 and r2=0.81r^2 = 0.81r2=0.81
r=1.05r = 1.05r=1.05 and r2=1.1025r^2 = 1.1025r2=1.1025
r=0.30r = 0.30r=0.30 and r2=0.90r^2 = 0.90r2=0.90
644 exam-style questions on OCR A Level Psychology Research methods and techniques. Each one has a worked solution and a mark scheme showing where the marks go.