catalyst
Comparing the Yield of Two Catalysts
Description
The catalyst data frame is a design object. Its eight rows
represent all possible combinations of two
temperatures, two concentrations, and two catalysts. The fourth
column represents the response variable Yield .
This data frame contains the following columns:
Arguments
| Temp |
a factor giving one of two temperatures, 160 or 180 degrees.
|
| Conc |
a factor giving one of two concentrations levels, 20 or 40 .
|
| Cat |
a factor giving one of two catalysts, A or B .
|
| Yield |
the numeric response variable.
|
Source
Box, G. E., Hunter, W. G., and Hunter, S. (1978) Statistics for Experimenters.
J. Wiley and Sons, NY, p. 308.
John M. Chambers and Trevor J. Hastie, (eds.) Statistical Models in S,
Wadsworth and Brooks, Pacific Grove, CA 1992, pp. 147, 150--52.
Examples
data(catalyst)
aovcat<- aov(Yield ~ ., catalyst)
# the "." stands for all the variables in the data frame
# except the one to the left of the "~"