A repackaged diabetes dataset [Hastie and Efron (2012)] is a list of two different design matrices and a response vector with 442 observations [Efron et. al. (2004)]
The x matrix has been standardized to have unit L2 norm in each column and zero mean. The matrix x2 consists of x plus 54 interaction terms.
diabetes
A list of 3 data objects,
x: A data frame with 10 variables and 442 observations
y: a numeric response vector of 442 observations
x2: a design matrix including interaction terms with 64 columns and 442 observations.
Efron B., Hastie T., Johnstone I., and Tibshirani R. "Least Angle Regression" Annals of Statistics 32:407-499, 2004.
Hastie T. and Efron B. (2012). lars: Least Angle Regression, Lasso and Forward Stagewise. R package version 1.1. http://CRAN.R-project.org/package=lars