Author Question: Assume that you have a binomial experiment with p = 0.4 and a sample size of 50 . The variance of ... (Read 78 times)

karlynnae · **on:** Jun 24, 2018

Assume that you have a binomial experiment with p = 0.4 and a sample size of 50 . The variance of this distribution is _____.
a. 20
b. 12
c. 3.46
d. Not enough information is given to answer this question.

Question 2

Before the last presidential debates, 50 of registered votes indicated they were planning to vote for the incumbent president. In a recent poll of 1200 registered voters after the debates, 636 indicated they are planning to vote for the incumbent president. Has there been a significant increase in the proportion of registered voters who are planning to vote for the incumbent president?
a. State the null and alternative hypotheses to be tested.
b. Compute the test statistic.
c. The null hypothesis is to be tested using = .05 . Determine the critical value(s) for this test.
d. What do you conclude?
e. Compute the p-value.

snackralk · **Reply #1 on:** Jun 24, 2018

Answer to Question 1

b

Answer to Question 2

a. H0: p .50
Ha: p > .50
b. Test statistic z = 2.08 (rounded)
c. Critical z = 1.645 (one-tailed test)
d. Since 2.08 > 1.645, reject H0 and conclude that there has been a significant increase in the proportion of voters in favor of the incumbent president.
e. p-value = .0188