Preliminary data analyses indicate that it is reasonable to consider the assumpt
ID: 3232747 • Letter: P
Question
Preliminary data analyses indicate that it is reasonable to consider the assumptions for one-way ANOVA satisfied. Perform the required hypothesis test using the p-value approach. A consumer magazine wants to compare the lifetimes of ballpoint pens of three different types. The magazine takes a random sample of pens of each type in the following table. Illustrate the p-value approach in the diagram. Show all appropriate formulas and provide a "final" written conclusion.
Brand A 260 218 184 219
Brand B 181 240 162 218
Brand C 238 257 241 213
Does the data indicate that there is a difference in mean lifetime for the three brands of ballpoint pens? Use a=0.01
Explanation / Answer
applying one way ANOVA on above data:
as p value is greater then 0.01 level we do not have sufficient evidence to conclude that there is a difference in mean lifetime for the three brands of ballpoint pens
Groups Count Sum Average Variance brand A 4 881 220.25 966.9167 brand B 4 801 200.25 1242.917 brand C 4 949 237.25 330.9167 ANOVA Source of Variation SS df MS F P-value F crit Between Groups 2744 2 1372 1.619994 0.250655 8.021517 Within Groups 7622.25 9 846.9167 Total 10366.25 11