This Question: 1 pt 5 of 12 (0 complete) This Quiz: 12 pts possible Treatment Sh
ID: 2908303 • Letter: T
Question
This Question: 1 pt 5 of 12 (0 complete) This Quiz: 12 pts possible Treatment Sham Researchers conducted a study to determine whether magnets are effective in treating back pain. The results are shown in the table for the treatment (with magnets) group and the sham (or placebo) group. The results are a measure of reduction in back pain. Assume that the two samples are independent simple random samples selected from normally distributed populations, and do not assume that the populationn standard deviations are equal. Complete parts (a) and (b) below. Use a 0.05 significance level for both parts. ?? X0,57 79 24 0.39 a. Test the claim that those treated with magnets have a greater mean reduction in pain than those given a sham treatment. What are the nul and alternative hypotheses? The test statistic, t, is(Round to two decimal places as needed.) The P-value is(Round to three decimal places as needed) State the conclusion for the test ? the null hypothesis There ? sufficient evidence to support the claim that those treated with magnets have a greater mean reduction in pain than those given a sham treatment. Is it valid to argue that magnets might appear to be effective if the sample sizes are larger? Since the b. Construct a confidence interval suitable for testing the claim that those treated with magnets have a greater mean reduction in pain than those given a sham treatment V for those treated with magnets is ? the sample mean for those given a sham treatment, it | ? valid to argue that magnets might appear to be effective if the sample sizes are larger Round to three decimal places as needed)Explanation / Answer
(a) right choice is C.
t=(x1- - x2-)/sqrt(s12/n1+s22/n2)=(0.57-0.39)/sqrt(0.79*0.79/24+1.45*1.45/24)=0.18/0.3371=0.53
df=(s12/n1+s22/n2)2/((s12/n1)2/(n1-1)+(s22/n2)2/(n2-2))=36( whole number approximation)
P-value=0.298 ( this is one tailed p-value)
Accept the null hypothesis . There is not sufficient ................sham treatment.
please provide the options in the fill in the blanks of second part
(b) (1-alpha)*100% confidence interval =sample mean difference ±t(alpha/2)*SE(difference)
95% confidence =0.18±2.03*0.3371=0.18±0.68=(-0.4,0.86)
SE(difference)=sqrt(s12/n1+s22/n2)=sqrt(0.79*0.79/24+1.45*1.45/24)=0.3371