What Are The Properties Of Sampling Distribution Of Difference Between Proportions?

Properties of sampling distribution of difference between proportions:
1.    Mean= Up₁-p₂= p₁-p_{2     Where p is probability}
2.    Variance=S²p₁-p₂=p_Iq₁/n₁+p₂q₂/n₂   with replacement
3.    Variance=S²p₁-p₂=p₁q₁/n₁{N₁-n₁/N₁-1} + p₂q₂/n₂{N₂-n₂/N₂-1}    without replacement
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