Question

A presidential candidate wants to test the null hypothesis that he has the same support rate in Virginia and in Maryland. In a random sample from Virginia, 298 among 613 asked would vote for this candidate. In a random sample from Maryland, 365 among 707 asked would vote for this candidate. Perform a 2-sided test and compute the P-value to at least 2 significant digits

Answer 1

Given that,

For Virginia : n1 = 613, x1 = 298 and

For Maryland : n2 = 707, x2 = 365 and

The null and alternative hypotheses are,

H0 : p1 = p2

Ha : p1 ≠ p2

Pooled proportion is,

Test statistic is,

=> Test statistic = Z = -1.09

p-value = 2 * P(Z < -1.09) = 2 * 0.1379 = 0.2758

=> p-value = 0.2758