sample consists of 2000 people with 1439 of them having the
Solution
Sample X N Sample proportion
1 11 20 0.550000
2 1439 2000 0.719500
Test:H0: p1 =p2 ag. H1 : p1 not equals p2...
Difference = p1- p2
Estimate for difference: p1-p2 = -0.1695..
pooled sample proportion =p = ( p1*20 + p2*2000 ) / (2000+20) = 0.7178
standard error = SE = sqrt{ p * ( 1 - p ) * [ (1/n1) + (1/n2) ] } = 0.101138323082992 ....
test statistic = -0.1695 / 0.101138323082992 = -1.675923...
p-value = 0.09375328...
critical values = + or - 1.96..
test statistic is outside of the critical region...i.e, | test stat | < | critical value |.....
so, we accept H0...there is no evidence to conclude otherwise..
95% CI for difference: (-0.388419, 0.0494194).....
since 0 is inside(belonging to) the interval we should accept H0...
THE results are same..since the hypothesis test concludes that p1 = p2 and confidence interval concludes that p1 = p2...
