Question

A research team is interested in investigating the effectiveness of a new medication intended to reduce resting heart rate (beats per minute, BPM) in overweight patients. In order to test the medication, the researcher organizes a clinical trial with participants randomly assigned to receive either the new medication or a placebo. Suppose the following table represents the heart rates for a SRS from both groups.

Placebo Group	Treatment Group
71	67
71	66
68	64
67	64
68	65
69	64
70	59
70	63
69	71
72	64
73

A) Calculate the standard error for the difference in average heart rate between the groups.

B) Calculate the pooled standard error for the difference in average heart rate assuming equal variances.

		a. SE=1.114 b. SE=1.088
		a. SE=2.441 b. SE=2.119
		a. SE=2.003 b. SE=1.654

Answer 1

	Placebo		treatment
x1    =	69.82	x2      =	64.70
s1    =	1.83	s2      =	3.06
n1    =	11	n2     =	10

A)

standard error se=√(S21/n1+S22/n2)=

1.114

B)

Pooled Variance Sp2=((n1-1)s21+(n2-1)*s22)/(n1+n2-2)=

6.1967

standard error se =Sp*√(1/n1+1/n2)=

1.088

correct option is:

a. SE=1.114

b. SE=1.088