Discussion:
Q: A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of $5.29 with a standard deviation of $2.78. For the October 26 evening showing of the same movie, for a sample of 25 purchases the mean was $5.12 with a standard deviation of $2.05. The means appear to be very close, but not the variances. At alpha = .05, is there a difference in variances? Show all steps clearly. (Data are from a project by statistics students Kim Dyer, Amy Pease, and Lyndsey Smith.)
Hypotheses
Value of the test statistic
p-value
Decision rule with the p-value
Decision
Conclusion