This dataset includes data from two different types of wool and three different tension levels about the number warp breaks per loom.
The wool types are :
1.A
2.B
The tension levels are:
1.Low
2.Medium
3.High
A table of the spread of breaks over wool types is generated via the following code:
data(warpbreaks)
breakdown <- tapply(warpbreaks$breaks, warpbreaks$wool, summary)
breakdown
## $A
## Min. 1st Qu. Median Mean 3rd Qu. Max.
## 10.00 19.50 26.00 31.04 36.00 70.00
##
## $B
## Min. 1st Qu. Median Mean 3rd Qu. Max.
## 13.00 18.00 24.00 25.26 29.00 44.00
as you can see in the above table, the medinan level of breaks between the two types of wool is different by 2 and the difference between the two means is 5.78. Wool type A being the one with more warp breaks.
This difference in number spread is even more apparent in a graph:
plot(warpbreaks$wool, warpbreaks$breaks, type(p), main = "Warp Breaks Over Wool Type", xlab = "Wool Type", ylab = "Number of Breaks", col.main = "blue", col.axis = "green")
One can also see the difference in spread over the tension types of the looms:
plot(warpbreaks$tension, warpbreaks$breaks, type(p), main = "Warp Breaks Over Tension", xlab = "Tension", ylab = "Number of Breaks", col.main = "blue", col.axis = "green")