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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

References

None

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)

} # }