Use a line plot to:

·    Graphically compare a variable function (mean, count, sum, standard deviation, and so on) by two factors

·    View factor and interaction effects

Minitab optionally plots symbols connected by lines to represent variable functions for each pair of factor levels.

A textile manufacturer is interested in determining the factors that affect the breaking strength of a synthetic fiber. Researchers from the company sampled the output of four production machines and three operators selected at random in order to determine if these variables affect fiber strength. Each of the three operators obtained two observations while they worked at each of the four machines. Researchers looked at the mean strength for each operator on each machine.

Data: Fiber.MTW (available in the Sample Data folder).