In testing a proportion, normality of p can be assumed if nπ₀ ≥ 10 and n(1 - π₀) ≥ 10.

Question

Quizplus · Accepted Answer

These are the criteria for the normal approximation to the binomial distribution, which is used to test a proportion. If the sample size is large enough (i.e., the product of the sample size and the estimated proportion for both the success and failure outcomes is at least 10), then the distribution of sample proportions will be approximately normal, even if the distribution of the underlying population is not normal. Therefore, normality of p can be assumed if these criteria are met.

In Testing a Proportion, Normality of P Can Be Assumed