Uniformity trial of rice
lord.rice.uniformity.Rd
Uniformity trial of rice in Ceylon, 1929.
Usage
data("lord.rice.uniformity")
Format
A data frame with 560 observations on the following 5 variables.
field
field
row
row
col
column
grain
grain weight, pounds per plot
straw
straw weight, pounds per plot
Details
In 1929, eight fields 1/5 acre in size were broadcast seeded with rice at the Anuradhapura Experiment Station in the northern dry zone of Ceylon. After broadcast, the fields were marked into 10 ft by 10 ft squares. At harvest, weights of grain and straw were recorded.
Fields 10-14 were on one side of a drain, and fields 26-28 on the other side.
Each field was surrounded by a bund. Plots next to the bunds had higher yields.
Field width: 5 plots * 10 feet = 50 feet
Field length: 14 plots * 10 feet = 140 feet
Conclusions: "It would appear that plots of about 1/87 acre are the most effective."
Source
Lord, L. (1931). A Uniformity Trial with Irrigated Broadcast Rice. The Journal of Agricultural Science, 21(1), 178-188. https://doi.org/10.1017/S0021859600008029
Examples
if (FALSE) { # \dontrun{
library(agridat)
data(lord.rice.uniformity)
dat <- lord.rice.uniformity
# match table on page 180
## libs(dplyr)
## dat
## field grain straw
## <chr> <dbl> <dbl>
## 1 10 590 732
## 2 11 502 600
## 3 12 315 488
## 4 13 291 538
## 5 14 489 670
## 6 26 441 560
## 7 27 451 629
## 8 28 530 718
# There are consistently high yields along all edges of the field
# libs(lattice)
# bwplot(grain ~ factor(col)|field,dat)
# bwplot(grain ~ factor(col)|field,dat)
# Heatmaps
libs(desplot)
desplot(dat, grain ~ col*row|field,
flip=TRUE, aspect=140/50,
main="lord.rice.uniformity")
# bivariate scatterplots
# xyplot(grain ~ straw|field, dat)
} # }