Rail {nlme} | R Documentation |
Evaluation of Stress in Railway Rails
Description
The Rail
data frame has 18 rows and 2 columns.
Format
This data frame contains the following columns:
- Rail
-
an ordered factor identifying the rail on which the measurement was made.
- 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.
Details
Devore (2000, Example 10.10, p. 427) cites data from an article in Materials Evaluation on “a study of travel time for a certain type of wave that results from longitudinal stress of rails used for railroad track.”
Source
Pinheiro, J. C. and Bates, D. M. (2000), Mixed-Effects Models in S and S-PLUS, Springer, New York. (Appendix A.26)
Devore, J. L. (2000), Probability and Statistics for Engineering and the Sciences (5th ed), Duxbury, Boston, MA.