The amount of sludge buildup in an automobile engine can severely affect performance. In an article in the Vanagon Maintenance Guide, a technical editor discussed the advantages of synthetic...

The amount of sludge buildup in an automobile engine can severely affect performance. In an article in the Vanagon Maintenance Guide, a technical editor discussed the advantages of synthetic lubricants. Suppose an experiment was conducted to determine whether the sludge buildup in an automobile engine can be predicted by the oil viscosity, oxidation inhibitors, detergents, dispersants, and/or anti-wear additives. The data obtained were used to fit the multiple linear regression