1. (10 Points)

a. Consider the following survey response of a random sample of 900 U.S. citizens: 74% report that they support the idea that the rich should pay higher income taxes while 26% report that they oppose that idea. What is the 99% confidence interval for the true population percentage holding the supporting view?

b. Explain in words what your computed result signifies.

2. Consider the following two random samples:

x = 57; normal distribution; s= 6; N = 401

x = 57; normal distribution; s= 6; N = 1601

a. Compute the 95% confidence interval for from each sample. Show your calculations and results.

b. What important relationship does the difference in your two answers reveal? Explain.

3 (10 points) Consider the following set of data from a study of student satisfaction with their academic experience. The scores come from a ten-point interval scale, with higher values indicating greater satisfaction. The students in the study were selected at random from a population of all students at Hotsy University. Here are their scores:

4.5 5.4 4.7 4.9 6.1 6.9 7.6 5.3 5.0 3.7 4.5 3.8 5.2 6.1 8.0

The researcher conducting the study mentioned in Q3. holds the hypothesis that the true population mean rating is 6.8.

a. State the researcher's null and alternate hypotheses

b. Calculate whether the null hypothesis should be accepted or rejected ( = .01)

c. Should the null hypothesis be accepted or rejected?

d. State your statistical rationale for your answer to c, including a reference to the possibility of being wrong.

1. (15 points) Consider the data from the following random samples drawn from two Universities (Hotsy from #3 and Totsy, its rival) assessing student satisfaction with their academic experience:

Hotsy: 4.5 5.4 4.7 4.9 6.1 6.9 7.6 5.3 5.0 3.7 4.5 3.8 5.2 6.1 8.0

Totsy: 5.5 6.1 4.2 4.9 5.7 4.5 6.2 5.4 6.8 4.1 2.9 3.2 4.7 5.7 7.2

a. Assess whether populations of students at the two schools have the same means

b. State the null and alternative hypotheses.

c. Compute the appropriate statistic ( = .05)

d. Decide to accept or reject the null hypothesis and state your rationale for doing so, including a reference to the possibility of being wrong.