morley                 package:base                 R Documentation

_M_i_c_h_a_e_l_s_o_n-_M_o_r_l_e_y _S_p_e_e_d _o_f _L_i_g_h_t _D_a_t_a

_D_e_s_c_r_i_p_t_i_o_n:

     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.

_U_s_a_g_e:

     data(morley)

_F_o_r_m_a_t:

     A data frame contains the following components:

     `_E_x_p_t' The experiment number, from 1 to 5.

     `_R_u_n' The run number within each experiment.

     `_S_p_e_e_d' Speed-of-light measurement.

_D_e_t_a_i_l_s:

     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.

_S_o_u_r_c_e:

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

_E_x_a_m_p_l_e_s:

     data(morley)
     morley$Expt <- factor(morley$Expt)
     morley$Run <- factor(morley$Run)
     attach(morley)
     plot(Expt, Speed, main = "Speed of Light Data", xlab = "Experiment No.")
     fm <- aov(Speed ~ Run + Expt, data = morley)
     summary(fm)
     fm0 <- update(fm, . ~ . - Run)
     anova(fm0, fm)
     detach(morley)

