As the end of the semester approaches, you wonder whether there is a relationship betweenthe number of exams a student has during the last week of class and the amount of sleep a student gets during that week. You collect a sample of 15 undergraduates and ask them to report the number of tests they had scheduled as well as the number of hours they slept during the final week of classes last semester.

8. For your sample, you find that SSx (number exams) = 25.6, SSy (hours sleep) = 1660, and the sum of products = -170. Calculate the Pearson correlation coefficient. (4)

You decide to use a simple regression analysis to examine whether a model with number of exams as a predictor can be used to explain variability in hours of sleep. Use the r value that you calculated in #8 in conjunction with the output in #11 below to answer the following questions.

9. Calculate b (the unstandardized slope coefficient; 4)

10. (standardized slope coefficient) is -0.82. Explain specifically what this value means. (2)

11. Fill in the blanks in the source table below (8). Hint: use R²; round to 2 decimal places both before and after squaring.

Model Sum of Squares df Mean Square F p-value

1 Regression _______ 1 ________ 26.68 .000

Residual _______ 13 ________

Total (SSy) 1660