In: Statistics and Probability
Conduct a test at the alphaαequals=0.01 level of significance by determining (a) the null and alternative hypotheses, (b) the test statistic, and (c) the P-value. Assume the samples were obtained independently from a large population using simple random sampling.Test whether
p 1 greater than p 2p1>p2. The sample data are x1=118, n1=259, x2=141, and n2=313.
(a) Choose the correct null and alternative hypotheses below.
A.
Upper H 0 : p 1 equals p 2H0: p1=p2
versus Upper H 1 : p 1 greater than p 2H1: p1>p2
B.
Upper H 0 : p 1 equals p 2H0: p1=p2
versus Upper H 1 : p 1 not equals p 2H1: p1≠p2
C.
Upper H 0 : p 1 equals p 2H0: p1=p2
versus Upper H 1 : p 1 less than p 2H1: p1<p2
D.
Upper H 0 : p 1 equals 0H0: p1=0
versus Upper H 1 : p 1 not equals 0
B) Test the statistics
C) Find the P-value
Solution:
We are given that:
Level of significance =
x1 = 118, n1=259 then sample proportion =
x2=141, and n2=313. then sample proportion =
We have to test whether p1 > p2.
Part A) Choose the correct null and alternative hypotheses below.
Since we have to test p1 > p2, option A) is correct.
A) H0: p1=p2 Vs H1: p1>p2
Part B) Test statistic:
where
Thus we get:
Part C) Find P-value:
P-value = P( Z > z test statistic value)
P-value = P( Z > 0.12)
P-value = 1 - P( Z < 0.12)
To P( Z < 0.12) , look in z table for z = 0.1 and 0.02 and find corresponding area.
from z table , we get:
P( Z < 0.12) =0.5478
Thus
P-value = 1 - P( Z < 0.12)
P-value = 1 - 0.5478
P-value = 0.4522