Sugar-cane Disease Data

Description:

     The 'cane' data frame has 180 rows and 5 columns.  The data frame
     represents a randomized block design with 45 varieties of
     sugar-cane and 4 blocks.

Usage:

     cane

Format:

     This data frame contains the following columns:

     'n' The total number of shoots in each plot.

     'r' The number of diseased shoots.

     'x' The number of pieces of the stems, out of 50, planted in each
          plot.

     'var' A factor indicating the variety of sugar-cane in each plot.

     'block' A factor for the blocks.

Details:

     The aim of the experiment was to classify the varieties into
     resistant, intermediate and susceptible to a disease called "coal
     of sugar-cane" (carvao da cana-de-acucar).  This is a disease that
     is common in sugar-cane plantations in certain areas of Brazil.

     For each plot, fifty pieces of sugar-cane stem were put in a
     solution containing the disease agent and then some were planted
     in the plot. After a fixed period of time, the total number of
     shoots and the number of diseased shoots were recorded.

Source:

     The data were kindly supplied by Dr. C.G.B. Demetrio of Escola
     Superior de Agricultura, Universidade de Sao Paolo, Brazil.

References:

     Davison, A.C. and Hinkley, D.V. (1997)  _Bootstrap Methods and
     Their Application_. Cambridge University Press.