The exercise involving data in this and subsequent sections were designed to be solved using Excel.

Johnson Filtration, Inc. provides maintenance service for water-filtration systems. Suppose that in addition to information on the number of months since the machine was serviced and whether a mechanical or an electrical repair was necessary, the managers obtained a list showing which repairperson performed the service. The revised data follow.

Click on the datafile logo to reference the data.

Repair Time in Hours Months Since Last Service Type of Repair Repairperson 2.9 2 Electrical Dave Newton Mechanical 3,0 6 Dave Newton 4.8 Electrical Mechanical Electrical Bob Jones 1.8 3 Dave Newton 2,9 2 Dave Newton 4,9 Electrical Bob Jones 4.2 Mechanical Bob Jones 4.8 Mechanical Bob Jones 4.4 4 Electrical Bob Jones 4.5 6 Electrical Dave Newton O 00 a. Ignore for now the months since the last maintenance service (1) and the repairperson who performed the service. Develop the estimated simple linear regression equation to predict the repair time (y) qiven the type of repair (). Recall that 2 = 0 if the type of repair is mechanical and 1 if the type of repair is electrical (to 2 decimals). Time b. Does the equation that you developed in part (a) provide a good fit for the observed data? Explain. -Select your answer - C. Ignore for now the months since the last maintenance service and the type of repair associated with the machine. Develop the estimated simple linear regression equation to predict = 0 if Bob Jones performed the service and 1 if Dave Newton performed the service (to 2 decimals). the repair time given the repairperson who performed the service. Let Time Select your answer Person d. Does the eguation that vou develoned in part (c) provide a good fit for the observed data? Explain. Repairperson is a better predictor of repair time than the type of repair Both predictors are about the same Type of repair is a better predictor of repair time than the repairperson