A group of 13 children and adolescents (considered healthy) participated in a psychological study designed to analyze the relationship between age and average total sleep time. (ATST). To obtain a measure for ATST (in minutes), recordings were taken on each subject on three consecutive nights and then average. The results obtained and displayed in the following table.

ATST 586 461.75 491.1 565 462 532.1 477.6 515.2 493 528.3 575.9 532.5 530.5

AGE 4.4 14 10.1 6.7 11.5 9.6 12.4 8.9 11.1 7.75 5.5 8.6 7.2

A) Obtain a 95% confidence interval for 0 (the in your textbook).

B) Find a 95% confidence interval to estimate the mean ATST when AGE = 10. Interpret your result.

C) Calculate and interpret a 95% PI for ATST when AGE =10.

D) What is the meaning of R2 (the coefficient of determination) in context of this study?