Heat evolved during setting of 13 cement mixtures of four basic ingredients. Each
ingredient percentage appears to be rounded down to a full integer. The sum of the four mixture
percentages varies from a maximum of 99% to a minimum of 95%. If all four regressor
X-variables always summed to 100%, the centered X-matrix would then be of rank only 3. Thus, the
regression of heat on four X-percentages is ill-conditioned, with an approximate rank deficiency
of MCAL = 1.
Usage
data(haldport)
Format
A data frame with 13 observations on the following 5 variables.
p3ca
Integer percentage of 3CaO.Al2O3 in the mixture.
p3cs
Integer percentage of 3CaO.SiO2 in the mixture.
p4caf
Integer percentage of 4CaO.Al2O3.Fe2O3 in the mixture.
p2cs
Integer percentage of 2CaO.SiO2 in the mixture.
heat
Heat (cals/gm) evolved in setting, recorded to nearest tenth.
Details
The (RXshrink) haldport data are identical to the (MASS) cement data except for
variable names.
Source
Woods H, Steinour HH, Starke HR. "Effect of composition of Portland cement on heat
evolved during hardening. Industrial Engineering and Chemistry 1932; 24: 1207-1214.
References
Hald A. Statistical Theory with Engineering Applications. 1952 (page 647.) New York; Wiley.