The sample data table Michelson.jmp contains data (as reported by Stigler, 1977) collected to determine the speed of light in air. Five separate collections of data were made in 1879 by Michelson, and the speed of light was recorded in km/sec. The values for velocity in this table have had 299,000 subtracted from them.
(a) The true value (accepted today) for the speed of light is 299,792.5 km/sec. What is the mean of Michelson’s responses?
(b) Is there a significant statistical difference between the trials? Use an ANOVA or a Welch ANOVA (whichever is appropriate) to justify your answer.
(c) Using Student’s t comparison circles, find the group of observations that is statistically different from all the other groups.
(d) Does excluding the result in part (c) improve Michelsonʹs prediction?
