morley {datasets}

R Documentation

Michaelson-Morley Speed of Light Data

Description

The classical data of Michaelson and Morley on the speed of light. The data consists of five experiments, each consisting of 20 consecutive ‘runs’. The response is the speed of light measurement, suitably coded.

Usage

morley

Format

A data frame contains the following components:

Expt

The experiment number, from 1 to 5.

Run

The run number within each experiment.

Speed

Speed-of-light measurement.

Details

The data is here viewed as a randomized block experiment with ‘experiment’ and ‘run’ as the factors. ‘run’ may also be considered a quantitative variate to account for linear (or polynomial) changes in the measurement over the course of a single experiment.

Source

A. J. Weekes (1986) A Genstat Primer. London: Edward Arnold.

Examples

require(stats); require(graphics)
morley$Expt <- factor(morley$Expt)
morley$Run <- factor(morley$Run)

xtabs(~ Expt + Run, data = morley)# 5 x 20 balanced (two-way)
plot(Speed ~ Expt, data = morley,
     main = "Speed of Light Data", xlab = "Experiment No.")
fm <- aov(Speed ~ Run + Expt, data = morley)
summary(fm)
fm0 <- update(fm, . ~ . - Run)
anova(fm0, fm)

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