haldCement {doBy} | R Documentation |
Heat development in cement under hardening related to the chemical composition.
data(haldCement)
A data frame with 13 observations on the following 5 variables.
x1
Percentage (weight) of [3Ca0][Al2O3]
x2
Percentage (weight) of [3Cao][SiO2]
x3
Percentage (weight) of [4Ca0][Al2O3][Fe03]
x4
Percentage (weight) of [2Cao][SiO2]
y
Heat development measured in calories per gram cement after 180 days
Anders Hald (1949); Statistiske Metoder; Akademisk Forlag (in Danish), page 509.
data(haldCement) if( interactive() ){ pairs( haldCement ) } m <- lm( y~x1+x2+x3+x4, data=haldCement ) summary( m ) # Notice: The model explains practically all variation in data; # yet none of the explanatory variables appear to be statistically # significant...