Required information:  Anticipated population = p1 and p2  Confidence level = 100 (1-α) %  Absolute precision required on either side of the true value of the difference between the proportions (in percentage points) = d  Intermediate value = v = [p1 (1-p1) + p2(1-p2)]  For any value of d, the sample size required will be largest when both p1 and p2 are equal to 50% therefore if it is not possible to estimate either population proportion, the safest choice of 0.5 should be used in both cases.
{"Image DocumentName": "Estimating the difference between two population proportions with specified absolute precision", "Image ImageDescription": "Required information: Anticipated population = p1 and p2. Confidence level = 100 (1-\u03b1) % Absolute precision required on either side of the true value of the difference between the proportions (in percentage points) = d. Intermediate value = v = [p1 (1-p1) + p2(1-p2)] For any value of d, the sample size required will be largest when both p1 and p2 are equal to 50% therefore if it is not possible to estimate either population proportion, the safest choice of 0.5 should be used in both cases. Formula: n= Z\u00b2\u2081-\u03b1[p1(1-p1)+p2(1-p2)]\u00b2/d\u00b2.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}