Machines                package:nlme                R Documentation

Productivity Scores for Machines and Workers

Description:

     The 'Machines' data frame has 54 rows and 3 columns.

Format:

     This data frame contains the following columns:

     Worker an ordered factor giving the unique identifier for the
          worker.

     Machine a factor with levels 'A',  'B', and  'C' identifying the
          machine brand.

     score a productivity score.

Details:

     Data on an experiment to compare three brands of machines used in
     an industrial process are presented in Milliken and Johnson (p.
     285, 1992). Six workers were chosen randomly among the employees
     of a factory to operate each machine three times. The response is
     an overall productivity score taking into account the number and
     quality of components produced.

Source:

     Pinheiro, J. C. and Bates, D. M. (2000), _Mixed-Effects Models in
     S and S-PLUS_, Springer, New York.  (Appendix A.14)

     Milliken, G. A. and Johnson, D. E. (1992), _Analysis of Messy
     Data, Volume I: Designed Experiments_, Chapman and Hall, London.

Examples:

     data(Machines)

