Description
Question 1
Last week we discussed the one sample hypothesis test. This week we will discuss ANOVA. The ANOVA allows us to test the mean between two or more groups.
Teachers Example, I have five pizza delivery areas and I want to know if the average sales per run is different in one area than any of the other areas.
H0: There is no significant difference in the sales per run between the delivery areas
H1: There is a significant difference in the sales per run between the delivery areas
Notice how the hypothesis is very simple. There is a difference or there is not a difference. Again, we will use MegaStat. You cannot calculate ANOVA by hand.
Just put your own sales for each area in a column and click the Megastat menu, select analysis of variance, and highlight your data and click enter. Check your p-value. Interpret.
Here is the teachers example :
Area 1 Area 2 Area 3 Area 4 Area 5
$ 45.00 $ 13.00 $ 12.00 $ 34.00 $ 37.00
$ 34.00 $ 24.00 $ 37.00 $ 25.00 $ 22.00
$ 36.00 $ 34.00 $ 27.00 $ 23.00 $ 32.00
$ 45.00 $ 23.00 $ 17.00 $ 36.00 $ 42.00
$ 53.00 $ 32.00 $ 28.00 $ 23.00 $ 35.00
$ 43.00 $ 21.00 $ 39.00 $ 35.00 $ 37.00
$ 45.00 $ 23.00 $ 35.00 $ 45.00 $ 28.00
$ 65.00 $ 24.00 $ 26.00 $ 34.00 $ 13.00
$ 32.00 $ 37.00 $ 45.00 $ 23.00 $ 24.00
$ 30.00 $ 45.00 $ 27.00 $ 53.00 $ 15.00
$ 40.00 $ 32.00 $ 34.00 $ 29.00 $ 63.00
$ 23.00 $ 34.00 $ 16.00 $ 28.00 $ 35.00
One factor ANOVA
Mean n Std. Dev
32.45 40.917 12 11.1719 Area 1
32.45 28.500 12 8.6707 Area 2
32.45 28.583 12 9.9951 Area 3
32.45 32.333 12 9.3355 Area 4
32.45 31.917 12 13.3448 Area 5
32.450 60 11.2347 Total
ANOVA table
Source SS df MS F p-value
Treatment 1,230.4333 4 307.60833 2.72 .0386
Error 6,216.4167 55 113.02576
Total 7,446.8500 59
The p-value is less than .05 so I do not reject the null
