Question

Exercise 17.15 described a study of the effectiveness of the ACT device for patients diagnosed with essential tremor. Estimate with 95% confidence the mean tremor amplitude in the population of similar patients when using the ACT device. Follow the four-step process.

Data from 17.15

Subject	1	2	3	4	5	6	7	8	9	10	11
ACT off	1.2	1.6	2	1	1.7	1.9	0.8	1.7	1.6	0.5	1.4
ACT on	0.3	0.2	0.6	0.2	0.5	0.4	0.2	0.6	0.3	0.2	0.1

Answer 1

this is paired sample t test

using excel

data -> data analysis -> t test paired

t-Test: Paired Two Sample for Means
	act off	act on
Mean	1.4	0.327272727
Variance	0.224	0.030181818
Observations	11	11
Pearson Correlation	0.66890737
Hypothesized Mean Difference	0
df	10
t Stat	9.369802048
P(T<=t) one-tail	1.43849E-06
t Critical one-tail	1.812461123
P(T<=t) two-tail	2.87698E-06
t Critical two-tail	2.228138852

p-value for one sided test = 1.43849E-06 <<0.05

hence we reject the null hypothesis

and we conclude that mean has decreased