An educational psychologist calculates a Pearson's r r\,r correlation coefficient to investigate the relationship between the number of hours students spend using an interactive learning app and their final exam scores. Which of the following values is mathematically impossible as a resulting correlation coefficient for this inferential test?
+1.12+1.12+1.12
−0.98-0.98−0.98
+0.05+0.05+0.05
−0.15-0.15−0.15
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.