A survey of food allergies in a simple random sample of 184 young children found that 13 had some kind of food allergy. What is the margin of error for a plus four 95% confidence interval for the true population proportion of young children who have a food allergy?

Question

Quizplus · Accepted Answer

The plus four method adds 2 successes and 2 failures to the sample, making the sample size 188 and the number of successes 15. The margin of error is calculated using the formula for a confidence interval for a proportion, resulting in approximately 0.0387.

A Survey of Food Allergies in a Simple Random Sample