draper.safflower.uniformity | R Documentation |
Uniformity trial of safflower in Arizona in 1958.
data("draper.safflower.uniformity")
A data frame with 640 observations on the following 4 variables.
expt
experiment
row
row
col
column
yield
yield per plot (grams)
Experiments were conducted at the Agricultural Experiment Station Farm at Eloy, Arizona. The crop was harvested in July 1958.
The crop was planted in two rows 12 inches apart on vegetable beds 40 inches center to center.
In each test, the end ranges and one row of plots on one side were next to alleys, and those plots gave estimates of border effects.
Experiment E4 (four foot test)
Sandy streaks were present in the field. Average yield was 1487 lb/ac. A diagonal fertility gradient was in this field. Widening the plot was equally effective as lengthening the plot to reduce variability. The optimum plot size was 1 bed wide, 24 feet long. Considering economic costs, the optimum size was 1 bed, 12 feet long.
Field width: 16 beds * 3.33 feet = 53 feet
Field length: 18 ranges * 4 feet = 72 feet
Experiment E5 (five foot test)
Average yield 2517 lb/ac, typical for this crop. Combining plots lengthwise was more effective than widening the plots, in order to reduce variability. The optimum plot size was 1 bed wide, 25 feet long. Considering economic costs, the optimum size was 1 bed, 18 feet long.
Field width: 14 beds * 3.33 feet = 46.6 feet.
Field length: 18 ranges * 5 feet = 90 feet.
Data are from Table A & B of Draper, p. 53-56. Typed by K.Wright.
Arlen D. Draper. (1959). Optimum plot size and shape for safflower yield tests. Dissertation. University of Arizona. https://hdl.handle.net/10150/319371 Page 53-56.
None
## Not run:
library(agridat)
data(draper.safflower.uniformity)
dat4 <- subset(draper.safflower.uniformity, expt=="E4")
dat5 <- subset(draper.safflower.uniformity, expt=="E5")
libs(desplot)
desplot(dat4, yield~col*row,
flip=TRUE, tick=TRUE, aspect=72/53, # true aspect
main="draper.safflower.uniformity (four foot)")
desplot(dat5, yield~col*row,
flip=TRUE, tick=TRUE, aspect=90/46, # true aspect
main="draper.safflower.uniformity (five foot)")
# Draper appears to removed the border plots, but it is difficult to
# match his results exactly
dat4 <- subset(dat4, row>1 & row<20)
dat4 <- subset(dat4, col>1 & col<17)
dat5 <- subset(dat5, row>1 & row<20)
dat5 <- subset(dat5, col<15)
# Convert gm/plot to pounds/acre. Draper (p. 20) says 1487 pounds/acre
mean(dat4$yield) / 453.592 / (3.33*4) * 43560 # 1472 lb/ac
libs(agricolae)
libs(reshape2)
s4 <- index.smith(acast(dat4, row~col, value.var='yield'),
main="draper.safflower.uniformity (four foot)",
col="red")$uni
s4 # match Draper table 2, p 22
## s5 <- index.smith(acast(dat5, row~col, value.var='yield'),
## main="draper.safflower.uniformity (five foot)",
## col="red")$uni
## s5 # match Draper table 1, p 21
## End(Not run)
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