Researchers were interested in the relationship between age and systolic blood pressure (SBP). They know from previous studies that both variables are approximately normally-distributed in most adult populations. Data were collected from 20 randomly selected adults enrolled at a family health team in Hamilton. The data are provided in the table below. Use these data to answer the questions below the table. Assume a 95% confidence level for all tests. Patient Id Age (years) SBP (mmHg) 1 20 120 2 43 128 3 63 141 4 26 126 5 53 134 6 31 128 7 58 136 8 46 132 9 58 140 10 70 144 11 46 128 12 53 136 13 70 146 14 20 124 15 63 143 16 43 130 17 26 124 18 19 121 19 31 126 20 23 123 Calculate the 95% confidence interval for the mean SBP and the 95% prediction interval for the SBP of a person who is 25 years old. Use the method described on page 381 of the textbook to calculate the confidence and prediction intervals (uses Minitab). Interpret the two intervals. Which one is larger, and why?.

1. Researchers were interested in the relationship between age and systolic blood pressure (SBP).
They know from previous studies that both variables are approximately normally-distributed in
most adult populations. Data were collected from 20 randomly selected adults enrolled at a
family health team in Hamilton. The data are provided in the table below. Use these data to
answer the questions below the table. Assume a 95% confidence level for all tests.
Patient Id Age (years) SBP (mmHg) 1 20 120 2 43 128 3 63 141 4 26 126 5 53 134 6 31 128 7
58 136 8 46 132 9 58 140 10 70 144 11 46 128 12 53 136 13 70 146 14 20 124 15 63 143 16 43
130 17 26 124 18 19 121 19 31 126 20 23 123
Calculate the 95% confidence interval for the mean SBP and the 95% prediction interval for the
SBP of a person who is 25 years old. Use the method described on page 381 of the textbook to
calculate the confidence and prediction intervals (uses Minitab). Interpret the two intervals.
Which one is larger, and why?