In: Statistics and Probability
As part of a study designed to compare hybrid and similarly equipped conventional vehicles, a group tested a variety of classes of hybrid and all-gas model cars and sport utility vehicles (SUVs). Suppose the following data show the miles-per-gallon rating obtained for two hybrid small cars, two hybrid midsize cars, two hybrid small SUVs, and two hybrid midsize SUVs; also shown are the miles per gallon obtained for eight similarly equipped conventional models.
Class | Type | MPG |
---|---|---|
Small Car | Hybrid | 36 |
Small Car | Conventional | 29 |
Small Car | Hybrid | 43 |
Small Car | Conventional | 33 |
Midsize Car | Hybrid | 28 |
Midsize Car | Conventional | 22 |
Midsize Car | Hybrid | 33 |
Midsize Car | Conventional | 24 |
Small SUV | Hybrid | 27 |
Small SUV | Conventional | 21 |
Small SUV | Hybrid | 28 |
Small SUV | Conventional | 22 |
Midsize SUV | Hybrid | 23 |
Midsize SUV | Conventional | 19 |
Midsize SUV | Hybrid | 24 |
Midsize SUV | Conventional | 18 |
At the α = 0.05 level of significance, test for significant effects due to class, type, and interaction.
Find the value of the test statistic for class. (Round your answer to two decimal places.)___
Find the p-value for class. (Round your answer to three decimal places.)
p-value = ____
State your conclusion about class.
Because the p-value ≤ α = 0.05, class is significant.
Because the p-value > α = 0.05, class is not significant.
Because the p-value ≤ α = 0.05, class is not significant.
Because the p-value > α = 0.05, class is significant.
Find the value of the test statistic for type. (Round your answer to two decimal places.)___
Find the p-value for type. (Round your answer to three decimal places.)
p-value = ____
State your conclusion about type.
Because the p-value > α = 0.05, type is not significant.
Because the p-value > α = 0.05, type is significant.
Because the p-value ≤ α = 0.05, type is significant.
Because the p-value ≤ α = 0.05, type is not significant.
Find the value of the test statistic for interaction between class and type. (Round your answer to two decimal places.)___
Find the p-value for interaction between class and type. (Round your answer to three decimal places.)
p-value = ____
State your conclusion about interaction between class and type.
Because the p-value ≤ α = 0.05, interaction between class and type is significant.
Because the p-value > α = 0.05, interaction between class and type is significant.
Because the p-value ≤ α = 0.05, interaction between class and type is not significant.
Because the p-value > α = 0.05, interaction between class and type is not significant.
The two factors ANOVA with replication analysis is performed in excel by following these steps,
Step 1: Write the data values in excel. The screenshot is shown below,
Step 2: DATA > Data Analysis > ANOVA: Two Factor With Replication > OK. The screenshot is shown below,
Step 3: Select Input Range: All the data values column, Rows per Sample: 2, Alpha = 0.05. The screenshot is shown below,
The result is obtained. The screenshot is shown below,
Class
test statistic for class (F-statistic) = 147.08
p-value for class = 0.000
conclusion: Because the p-value ≤ alpha = 0.05, class is
significant.
Type
test statistic for type (F-statistic) = 29.76
p-value for type = 0.000
conclusion: Because the p-value ≤ alpha = 0.05, type is
significant.
interaction between class and type
test statistic for interaction (F-statistic) = 0.39
p-value for interaction = 0.761
conclusion: Because the p-value > alpha = 0.05, interaction
between class and type is not significant.