estimation of difference among population

Question

Estimation of difference among population proportions

Assume the two proportions be described by P1 and P2, respectively,Then the difference absolute between the two proportions is described by (P₁ - P₂)

The standard error is described by:-

S_{(P1 - P2)} = √{(pq/n₁) + (pq/n₂)}  =   where p = (p₁n₁ + p₂n₂)/(n₁ + n₁)  and q = 1 - p

Then described the confidence level, the confidence interval among the two population proportions is described by

(P1 - P2) ± Confidence level S_{(P1 - P2)}

= (P1 - P2) ± Z  √{(pq/n₁) + (pq/n₂)} 

Whereas P = (p₁n₁ + p₂n₂)/(n₁ + n₁)  always remember to convert P₁ and P₂ to P.