Spruce                 package:nlme                 R Documentation

Growth of Spruce Trees

Description:

     The 'Spruce' data frame has 1027 rows and 4 columns.

Format:

     This data frame contains the following columns:

     Tree a factor giving a unique identifier for each tree.

     days a numeric vector giving the number of days since the
          beginning of the experiment.

     logSize a numeric vector giving the logarithm of an estimate of
          the volume of the tree trunk.

     plot a factor identifying the plot in which the tree was grown.

Details:

     Diggle, Liang, and Zeger (1994, Example 1.3, page 5) describe data
     on the growth of spruce trees that have been exposed to an
     ozone-rich atmosphere or to a normal atmosphere.

Source:

     Pinheiro, J. C. and Bates, D. M. (2000), _Mixed-Effects Models in
     S and S-PLUS_, Springer, New York.  (Appendix A.28)

     Diggle, Peter J., Liang, Kung-Yee and Zeger, Scott L. (1994),
     _Analysis of longitudinal data_, Oxford University Press, Oxford.

Examples:

     data(Spruce)

