To test whether the mean time needed to mix a batch of mater
To test whether the mean time needed to mix a batch of material is the same for machines produced by three manufacturers, the Jacobs Chemical Company obtained the following data on the time (in minutes) needed to mix the material. Excel File: datal3-15.xls a. Use these data to test whether the population mean times for mixing a batch of material differ for the three manufacturers. Use a = .05. Compute the values below (to 2 decimals, if necessary). Sum of Squares, reatment Sum of Squares, Error Mean Squares, Treatment Mean Squares, Error Calculate the value of the test statistic (to 2 decimals).
Solution
Source of Variation SS df MS F P-value F crit Between Groups(Treatment) 104 2 52 10.63636 0.00426 4.256495 Within Groups(Error) 44 9 4.888889 Total 148 11 Sum of Squares,Treatment = 104 Sum of Squares,Error = 44 Mean Squares,Treatment = 52 Mean Squares,Error=4.88 Test statistics = 10.63