Statistical Literacy Consider a hypothesis test of difference of proportions for two independent populations. Suppose random samples produce r1 successes out of n1 trials for the first population and r2 successes out of n2 trials for the second population.

(a) What does the null hypothesis claim about the relationship between the proportions of successes in the two populations?

(b) What is the formula for the z value of the sample test statistic?

AppendixLO1