an industrial researcher tests 3 different keyboard designs for a new computer to determine which one produces optimal performance. four computer operators are given text material and are told to type the material as fast as they can. they spend 3 minutes on each keyboard with a 5 minute rest between each trial. the number of errors committed are recorded. do the following data indicate a significant difference among the 3 keyboard types? use a repeated measures anova to test at the .05 level of significance.
