A local supermarket in rural Brisbane wished to determine whether increasing advertising lead to an overall increase
Question:
A local supermarket in rural Brisbane wished to determine whether increasing advertising lead to an overall increase in profit. It was known that they (on average) make $525 profit per hour, with a variance of $900. They planned to test the profit data after the new advertisement schemes were implemented, using a random sample of 60 hours of operation and indicating that they were prepared to accept a Type I error probability of 0.05.
1. State the direction of the alternative hypothesis for the test. Type gt (greater than), ge (greater than or equal to), lt (less than), le (less than or equal to) or ne (not equal to) as appropriate in the box.
2. State, in absolute terms, the critical value as found in the tables in the textbook.
3. Determine the lower boundary of the region of non-rejection in terms of the sample mean used in testing the claim (to two decimal places). If there is no (theoretical) lower boundary, type lt in the box.
4. If the average profit per hour found from the sample is $537, is the null hypothesis rejected for this test? Type yes or no.
5. From your findings in (d), what is the value of the test statistic (to two decimal places).
6. Disregarding your answer for 4, if the null hypothesis was rejected when the new advertisement scheme was tested, could it be concluded that increasing advertising increased the profit per hour at the 5% level of significance? Type yes or no.
Elementary Statistics
ISBN: 978-0538733502
11th edition
Authors: Robert R. Johnson, Patricia J. Kuby