Uniformity trial of maize, oat, alfalfa, mangolds

Usage

data("summerby.multi.uniformity")

Format

A data frame with 2600 observations on the following 6 variables.

col: column ordinate
row: row ordinate
yield: yield
range: range (block in field)
year: year
crop: crop

Details

Note that the plots for each range are the same across years. For example the plots in range R2 are the same in 1922, 1923, 1924, 1925.

Grown at Macdonald College, Quebec. Four ranges of land each 760 x 100 links were used. In years 1922-1926, all crops were harvested in 20 link by 20 links plots.

In oats, the yields are for cleaned grain. In mangolds and alfalfa, the yields of dry matter were calculated. In maize, the green weights of fodder were obtained. In 1925, range R3 oats were damaged by birds. In 1927, range R4 oats were lodges and not harvested. In 1924 range R5 had some flooding and is considered 'inadvisable' for use. In 1914 range R3 oat yield was variable, perhaps from poor germination. Data are included here for completeness, but should perhaps not be included.

The row numbers in this data are based on the figure on page 13 of Summerby. Row 1 is at the bottom. There appears to be approximately a blank row between ranges.

The paper by Summerby has more year/range combinations, but those plots are 20 links by 100 links and are only a single plot wide.

These data were converted from PDF to png images, then OCR converted to text, then hand-checked by K.Wright.

Source

Summerby, R. (1934). The value of preliminary uniformity trials in increasing the precision of field experiments. Macdonald College. https://books.google.com/books?id=6zlMAAAAYAAJ&pg=RA14-PA47

References

None

Examples

if (FALSE) { # \dontrun{
  library(agridat)
  data(summerby.multi.uniformity)
  dat <- summerby.multi.uniformity

  libs(desplot)
  dat <- mutate(dat, env=paste(range, year, crop))
  desplot(dat, yield ~ col*row|env, aspect=(5*20)/(35*20),
          main="summerby.multi.uniformity")

  # Show all ranges for a single year.
  # dat 

  # Compare the variance for each dataset in Summerby, page 18, column (a)
  # with what we calculate.  Very slight differences.
  # libs(dplyr)
  # dat 
  ## range  year       var  summerby
  ##  1 R2     1922  82404      82404
  ##  2 R2     1923 254780.    254780  
  ##  3 R2     1924 111978.    111978  
  ##  4 R2     1925  84515.     84515  
  ##  5 R2     1926 101008.    100960  
  ##  6 R3     1922 185031.    185031  
  ##  7 R3     1923 154777.    154784 
  ##  8 R3     1924 252451.    252451  
  ##  9 R3     1926 472087.    472088  
  ## 10 R4     1924     19.3       19.341 
  ## 11 R4     1925     14.2       14.234 
  ## 12 R4     1926     14.2       14.236 
  ## 13 R5     1924 134472.    134472  
  ## 14 R5     1925 289001.    289026  
  ## 15 R5     1926 131714.    131714  
  ## 16 R5     1927      8.62       8.622

} # }