In: Math
Consider the hypothesis statement to the right using alphaequals0.01 and the data to the right from two independent samples. a) Calculate the appropriate test statistic and interpret the result. b) Calculate the p-value and interpret the result. Click here to view page 1 of the standard normal table. LOADING... Click here to view page 2 of the standard normal table. LOADING... H0: mu1minusmu2less than or equals0 H1: mu1minusmu2greater than0 x overbar1 equals 88 x overbar2 equals 82 sigma1 equals 24 sigma2 equals 20 n1 equals 45 n2 equals 55 a) The test statistic is nothing. (Round to two decimal places as needed.)
Solution
Hypotheses:
Null: H0: (µ1 - µ2) ≤ 0 Vs Alternative: H1: (µ1 - µ2) > 0
Test Statistic:
Z = (X1bar – X2bar)/√{(σ12/n1)+(σ22/n2)} = 1.34
where
X1bar and X2bar are sample averages based on n1 observations on X1 and n2 observations on X2
σ1, σ2 are respective population standard deviations.
Calculations
Summary of Excel calculations is given below:
n1 |
45 |
n2 |
55 |
X1bar |
88.00 |
X2bar |
82.00 |
σ1 |
24 |
σ2 |
20 |
σ12 |
576 |
σ22 |
400 |
Zcal |
1.339208 |
α |
0.01 |
p-value |
0.090251 |
σ12/n1 |
12.8 |
σ22/n2 |
7.272727 |
Sum |
20.07273 |
Sqrt |
4.48026 |
1- α |
0.99 |
Distribution, and p-value:
Under H0, Z ~ N(0, 1),
Hence, p-value = P(Z > Zcal).
Using Standard Normal Table, the p-value is found to be as shown in the above table:
Decision:
Since p-value > α, H0 is accepted.
Conclusion:
There is not sufficient evidence to suggest that the difference between the two population means is greater than zero. Answer
DONE