z pvalueSolutionHere we have to test the hypothesis that H0
z=______
p-value=____
Solution
Here we have to test the hypothesis that,
H0 : p = 0.48 Vs H1 : p 0.48
where p is the population proportion of households with no children
given that ,phat = 0.43
variance of p^ = [ p*(1-p) / n ]
n = number of respondants in a christmas tree market survey = 420
variance = ( 0.48*0.52 ) / 420 = 0.000594
sd = sqrt(0.000594) = 0.024378
The test statistic for testing proportion is,
Z = (p^ - p) / sd
= (0.43 - 0.48) / 0.024378
Z = -2.05
P( |z| > 2.05) = 0.0202
alpha = 0.1
P-value command in EXCEL,
=NORMSDIST(z)
where z is the test statistic value.
P-value < alpha
Reject H0 at 0.1 significance level.
We conclude that the proportion of households with no children differs from 48%.
