The blood-pressure.txt data deals with the treatment of essential hypertension (essential is a technical term meaning that the cause is unknown; a synonym is idiopathic) and is from a paper by Vlachakis and Mendlowitz. Seventeen patients received control treatment first and propranolol treatment second. The data in blood-pressure.txt consist of the systolic blood pressure in the recumbent position. (Note: you can use SAS or R to solve this problem.)

(a) Take the differences between the systolic blood pressure on propranolol treatment vs control. Use the sign test to test for a treatment effect of propranolol (2-sided test).

(b) Take the differences between the systolic blood pressure on propranolol treatment vs control. Use the Wilcoxon sign rank test to test for a treatment effect of propranolol (2-sided test).

PID Cont Trt 1 185 140 2 160 124 3 190 131 4 192 137 5 218 150 6. 200 135 7 210 139 8 225 153 9 190 144 10 180 134 11 176 137 12 200 155 13 188 128 14 200 133 15 178 138 16 180 130 17 150 127