data_y: Simulated response variable
Description
The response variable is simulated from the functional form of
$data_y = sin(2*pi*x1) + 4*(1-x2)*(1+x2) + 2*x3/(1+0.8*x3*x3) + rnorm(1,0,0.9)$, where x1, x2 and x3 are
simulated from a uniform distribution between 0 and 1.format
A data matrix of 100 by 1