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.