Effectiveness of Insect Sprays

Description

The counts of insects in agricultural experimental units treated with different insecticides.

Usage

InsectSprays

Format

A data frame with 72 observations on 2 variables.

Source

⁠Beall (1942).

References

⁠Beall G (1942). “The Transformation of Data from Entomological Field Experiments so that the Analysis of Variance Becomes Applicable.” Biometrika, 32(3–4), 243–262. doi:10.1093/biomet/32.3-4.243.

⁠McNeil D (1977). Interactive Data Analysis: A Practical Primer. John Wiley & Sons. ISBN 978-0471026310.

Examples

require(stats); require(graphics)
boxplot(count ~ spray, data = InsectSprays,
        xlab = "Type of spray", ylab = "Insect count",
        main = "InsectSprays data", varwidth = TRUE, col = "lightgray")
fm1 <- aov(count ~ spray, data = InsectSprays)
summary(fm1)
opar <- par(mfrow = c(2, 2), oma = c(0, 0, 1.1, 0))
plot(fm1)
fm2 <- aov(sqrt(count) ~ spray, data = InsectSprays)
summary(fm2)
plot(fm2)
par(opar)