xmp10.10 {Devore5}R Documentation

data from Example 10.10

Description

The xmp10.10 data frame has 18 rows and 2 columns.

Format

This data frame contains the following columns:

travel
a numeric vector giving the travel time for ultrasonic head-waves in the rail (nanoseconds). The value given is the original travel time minus 36,100 nanoseconds.
Rail
an ordered factor identifying the rail on which the measurement was made.

Details

Data from a study of travel time for a certain type of wave that results from longitudinal stress of rails used for railroad track.

Source

Devore, J. L. (2000), Probability and Statistics for Engineering and the Sciences (5th ed), Duxbury, Boston, MA.

Pinheiro, J. C. and Bates, D. M. (2000), Mixed-Effects Models in S and S-PLUS, Springer, New York. (Appendix A.26)

(1985), ``Zero-force travel-time parameters for ultrasonic head-waves in railroad rail'', Materials Evaluation, 854-858.

Examples

data(xmp10.10)
xmp10.10$Rail <- factor(xmp10.10$Rail)
boxplot(travel ~ Rail, xmp10.10, col = "lightgray",
  xlab = "Rail", ylab = "Zero-force travel time (microsec)",
  main = "Travel times in rails, from example 10.10")
fm1 <- lm(travel ~ Rail, data = xmp10.10)
anova(fm1)