agridat (version 1.23)

rothamsted.oats: RCB experiment of oats, straw and grain, 9 fertilizer treatments

Description

RCB experiment of oats, straw and grain, 9 fertilizer treatments

Usage

data("rothamsted.oats")

Format

A data frame with 96 observations on the following 6 variables.

block

block

trt

fertilizer treatment with 9 levels

grain

grain, pounds per plot

straw

straw, pounds per plot

row

row

col

column

Details

Oats (Grey Winter) grown at Rothamsted, Long Hoos field 1926.

Values of grain and straw are actual weights in pounds. Each plot was 1/40 acre. The plot dimensions are not given, but the Rothamsted report shows the field being square.

The treatment codes are: OA,OB,OC,OD = No top dressing. E/L = Early/late application. S/M = Sulphate or muriate of ammonia. 1/2 = Single or double dressing.

References

McCullagh, P. and Clifford, D., (2006). Evidence for conformal invariance of crop yields, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Science, 462, 2119--2143. https://doi.org/10.1098/rspa.2006.1667

Examples

if (FALSE) {
  
  library(agridat)
  data(rothamsted.oats)
  dat <- rothamsted.oats

  
  libs(desplot)
  desplot(dat, grain~col*row,
          out1=block, text=trt, cex=1, shorten=FALSE,
          aspect=1,
          main="rothamsted.oats")
  desplot(dat, straw~col*row,
          out1=block, text=trt, cex=1, shorten=FALSE,
          aspect=1,
          main="rothamsted.oats")

  
  libs(lattice)
  xyplot(grain~straw, dat,
         main="rothamsted.oats") # traits are correlated


  if(0){
    # compare to summary at bottom of page 146, first 3 columns
    libs(dplyr)
    dat = mutate(dat,
                 nfert=trt, # number of fertilizer applications
                 nfert=dplyr::recode(nfert,
                                     "oa"="None", "ob"="None",
                                     "oc"="None", "od"="None",
                                     "1se"="Single", "1sl"="Single",
                                     "1me"="Single", "1ml"="Single",
                                     "2se"="Double", "2sl"="Double",
                                     "2me"="Double", "2ml"="Double"))
    # English ton = 2240 pounds, cwt = 112 pounds
    # multiply by 40 to get pounds/acre
    # divide by: 112 to get hundredweight/acre, 42 to get bushels/acre
    # Avoid pipe operator in Rd examples!
    dat <- group_by(dat, nfert)
    dat <- summarize(dat, straw=mean(straw), grain=mean(grain))
    dat <- mutate(dat, straw= straw * 40/112, grain = grain * 40/42)
    ## # A tibble: 3 x 3
    ##   nfert  straw grain
    ##      
    ## 1 Single  50.3  78.9
    ## 2 Double  53.7  77.7
    ## 3 None    44.1  75.4
  }

}