In: Statistics and Probability
4. An airline wants to know the impact of method of redeeming frequent-flyer miles and the age group of customers on how the number of miles they redeemed. To do so, they perform a two-way analysis of variance on the data for miles redeemed shown on cells L35 to O43 on the answers sheet. | |||||||||||
a. Identify the null and alternative hypotheses for each of the two main effects and the interaction. | |||||||||||
b. Use two-way analysis of variance to test each of these three sets of hypotheses at the 0.05 significance level. |
Customer age ranges | ||||
Methods of redeeming miles | Under 25 | 25 to 40 | 41 to 60 | Over 60 |
Cash | 300,000 | 60,000 | 40,000 | 0 |
0 | 0 | 25,000 | 5,000 | |
25,000 | 0 | 25,000 | 25,000 | |
Discount Vacations | 40,000 | 40,000 | 25,000 | 45,000 |
25,000 | 25,000 | 50,000 | 25,000 | |
0 | 5,000 | 0 | 0 | |
Discount Internet Shopping Spree | 25,000 | 30,000 | 25,000 | 30,000 |
25,000 | 25,000 | 50,000 | 25,000 | |
75,000 | 50,000 | 0 | 25,000 |
b. | SS | df | MS | Fcalc | Fcrit | p-value | |||||
Methods of redeeming miles | Reject H0or not? | α = | 0.05 | ||||||||
Customer age ranges | Reject H0or not? | α = | 0.05 | ||||||||
Interaction | Reject H0or not? | α = | 0.05 | ||||||||
Error |
Hypothesis 1
H0 : The mean number of miles redeemed is the same across age
groups
H1 : The mean number of miles redeemed is not the same across age
groups
Hypothesis 2
H0 : The mean number of miles redeemed is the same for all the
three methods of redeeming miles
H1 : The mean number of miles redeemed is not the same for all the
three methods of redeeming miles
Hypothesis 3
H0 : There in no interaction between the age group and the
method of redeeming.
H1: There in an interaction between the age group and the method of
redeeming.
2 ways anova in excel.
1. Input the data in excel as shown
2. Under the data tab, select the data analysis and select
two way anova with
replication.
3. Update the input in the dialogue box
4. The output is generated as follows.
We use the pvalue for testing the hypothesis.
(Highlighted in yellow).
Also the next to the anova output
is have indicated which pvalue correspond to which
variable.
Methods of redeeming miles
Here the pvalue 0.65 is greater than 0.05, hence we fail to reject
the null hypothesis and conclude that the mean number of miles
redeemed is the same for all the three methods of redeeming
miles
Age group
Here the pvalue 0.74 is greater than 0.05, hence we fail to reject
the null hypothesis and conclude that the mean number of miles
redeemed is the same for all the three methods of redeeming
miles
Interaction
Here the pvalue 0.85 is greater than 0.05, hence we fail to reject
the null hypothesis and conclude that there in no interaction
between the age group and the method of redeeming.