Use the data provided in this question for all remaining ANOVA-based questions in this assessment.

SCENARIO 1: An airline wants to select a computer software package for its reservation system. Four software packages (1, 2, 3, and 4) are commercially available. The airline will choose the package that bumps the fewest mean number of passengers as possible during a month. An experiment is set up in which each package is used to make reservations for 5 randomly selected weeks. (A total of 20 weeks was included in the experiment.) The number of passengers bumped each week is given below. Perform an ANOVA in order to test the difference in mean number of passengers bumped every week by the four packages.

Package 1: 12, 14, 9, 11, 16

Package 2: 2, 4, 7, 3, 1

Package 3: 10, 9, 6, 10, 12

Package 4: 7, 6, 6, 15, 12

SCENARIO 2: A company that employs a large number of salespeople is interested in learning which of the salespeople sell the most: those strictly on commission, those with a fixed salary, or those with a reduced fixed salary plus a commission. The previous month's records for a sample of salespeople are inspected and the amount of sales (in dollars) is recorded for each, as shown in the table. Perform an ANOVA in order to test the difference in mean amount of sales across the three employee types.

SCENARIO 3: Random samples of four different models of cars were selected and the gas mileage of each car was measured. The results are shown below.

Test the claim that the four different models have the same population mean.

SCENARIO 4: A consumer magazine wants to compare the lifetimes of ballpoint pens of three different types. The magazine takes a random sample of pens of each type in the following table.

Test the hypothesis that there is no difference in mean lifetime for the three brands of ballpoint pens.

NOTE: For all tests assume a 5% alpha level unless noted otherwise. Round answers to two places after the decimal point. Use Excel to generate ANOVA output.

Referring to Scenario 1, the null hypothesis is: