Factorial experiment of beans, 2x2x2x2
cochran.factorial.Rd
Factorial experiment of beans, 2x2x2x2.
Usage
data("cochran.factorial")
Format
A data frame with 32 observations on the following 4 variables.
rep
rep factor
block
block factor
trt
treatment factor, 16 levels
yield
yield (pounds)
d
dung treatment, 2 levels
n
nitrogen treatment, 2 levels
p
phosphorous treatment, 2 levels
k
potassium treatment, 2 levels
Details
Conducted by Rothamsted Experiment Station in 1936.
There were 4 treatment factors:
2 d dung levels: None, 10 tons/acre.
2 n nitrochalk levels: None, 0.4 hundredweight nitrogen per acre.
2 p superphosphate levels: None, 0.6 hundredweight per acre
2 k muriate of potash levels: None, 1 hundredweight K20 per acres.
The response variable is the yield of beans.
Source
Cochran, W.G. and Cox, G.M. (1957), Experimental Designs, 2nd ed., Wiley and Sons, New York, p. 160.
Examples
if (FALSE) { # \dontrun{
library(agridat)
data(cochran.factorial)
dat <- cochran.factorial
# Ensure factors
dat <- transform(dat, d=factor(d), n=factor(n), p=factor(p), k=factor(k))
# Cochran table 6.5.
m1 <- lm(yield ~ rep * block + (d+n+p+k)^3, data=dat)
anova(m1)
libs(FrF2)
aliases(m1)
MEPlot(m1, select=3:6,
main="cochran.factorial - main effects plot")
} # }