Gasoline
data frame has 32 rows and 6 columns.Atkinson, A. C. (1985), Plots, Transformations, and Regression, Oxford Press, New York.
Daniel, C. and Wood, F. S. (1980), Fitting Equations to Data, Wiley, New York
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S (4th ed), Springer, New York.
API
,
vapor
, and ASTM
---measure characteristics of the
crude oil used to produce the gasoline. The other covariate ---
endpoint
---is a characteristic of the refining process.
Daniel and Wood (1980) notice that the covariates characterizing
the crude oil occur in only ten distinct groups and conclude that the
data represent responses measured on ten different crude oil samples.