| warpbreaks {base} | R Documentation |
This data set gives the number of warp breaks per loom, where a loom corresponds to a fixed length of yarn.
data(warpbreaks)
A data frame with 54 observations on 3 variables.
| [,1] | breaks | numeric | The number of breaks |
| [,2] | wool | factor | The type of wool (A or B) |
| [,3] | tension | factor | The level of tension (L, M, H) |
L. H. C. Tippet (1950). Technological Applications of Statistics, Wiley, page 106.
Tukey, J. W. (1977). Exploratory Data Analysis. Addison-Wesley. McNeil, D. (1977). Interactive Data Analysis. Wiley.
data(warpbreaks)
summary(warpbreaks)
opar <- par(mfrow = c(1,2), oma = c(0, 0, 1.1, 0))
plot(breaks ~ tension, data = warpbreaks, col = "lightgray",
varwidth = TRUE, subset = wool == "A", main = "Wool A")
plot(breaks ~ tension, data = warpbreaks, col = "lightgray",
varwidth = TRUE, subset = wool == "B", main = "Wool B")
mtext("warpbreaks data", side = 3, outer = TRUE)
par(opar)
summary(fm1 <- lm(breaks ~ wool*tension, data = warpbreaks))
anova(fm1)