In: Statistics and Probability
Listed below are systolic blood pressure measurements (mm Hg) taken from the right and left arms of the same woman. Assume that the paired sample data is a simple random sample and that the differences have a distribution that is approximately normal. Use a 0.100.10 significance level to test for a difference between the measurements from the two arms. What can be concluded? Right arm 148148 133133 142142 130130 131131 Left arm 182182 164164 176176 149149 134134 In this example, mu Subscript dμd is the mean value of the differences d for the population of all pairs of data, where each individual difference d is defined as the measurement from the right arm minus the measurement from the left arm. What are the null and alternative hypotheses for the hypothesis test? A. Upper H 0H0: mu Subscript dμdnot equals≠0 Upper H 1H1: mu Subscript dμdgreater than>0 B. Upper H 0H0: mu Subscript dμdequals=0 Upper H 1H1: mu Subscript dμdless than<0 C. Upper H 0H0: mu Subscript dμdequals=0 Upper H 1H1: mu Subscript dμdnot equals≠0 D. Upper H 0H0: mu Subscript dμdnot equals≠0 Upper H 1H1: mu Subscript dμdequals=0 Identify the test statistic. tequals=nothing (Round to two decimal places as needed.) Identify the P-value. P-valueequals=nothing (Round to three decimal places as needed.) What is the conclusion based on the hypothesis test? Since the P-value is ▼ greater less than the significance level, ▼ reject fail to reject the null hypothesis. There ▼ is not is sufficient evidence to support the claim of a difference in measurements between the two arms.
Null and alternative hypotheses :
Two tailed test.
Test Statistic :
Where, is sample mean of differences.
is sample standard deviation of differences.
n is sample size ( Number of data pairs )
Calculation :
n = 5
So test statistic is ,
Test statistic = t = -4.05 ( rounded to two decimal places )
P-value :
P-value for this two tailed test is ,
P-value = 2*P( t < test statistic ) = 2*P( t < -4.048 )
Using Excel function , = T.DIST( t , df , 1 ) , df = n - 1 = 5 - 1 = 4
P( t < -4.048 ) = T.DIST( -4.048 , 4 , 1 ) = 0.00775
So, p-value = 2*0.00775 = 0.016
Conclusion :
Since the P-value ( 0.016 ) is less than the significance level ( = 0.10 ), so reject null hypothesis.
There is sufficient evidence to support the claim of a difference in measurements between the two arms.