Question

A study was conducted to measure the effectiveness of hypnotism in toucing pain. The measurements are contimeters on a pain scale before and after hypnosis. Assume that the pared sample data are simple random samples and that the differences have a distribution that is approximately normal Construct a 96% confidence interval for the mean of the before anererences. Does hypnotism appear to be effective in reducing point Before After 134 29 Construct a 95% confidence interval for the mean of the before her forences found to two decimal places as needed) Does hypnoti e ve in reducing point O A No, because the conhece erval does not induce and is entirely greater than er OB Yes, because the confidence interval does not include and is only greater than zero OC. Yes, because the confidence interval includes zero OD. No, because the confidence verval includes zero.

Answer 1

before after difference(d)=x1-x2 1.9 1.5 No com Ni 3.610000 2.250000 0.810000 22.090000 1.440000 2.890000 4.840000 1.690000 2d2=39.62 -1.7 2.2 total mean dbar= -1.3 Id=5.2 0.650 degree of freedom =n-1 7.000 Std deviaiton Sq=v(Ed?-(d)/n)/(n-1) = 2.275 std error=Se = /Vn = 0.804 2.365 for 95% Cl; and 7 degree of freedom, value of t= therefore confidence interval= sample mean -/+t*std error margin of errror =t*std error= 1.903 lower confidence limit -1.25 upper confidence limit 2.55

for above 95% confidence interval = (-1.25 , 2.55)

option D is correct: No because the confidence interval contains 0.