bo09_toy: Two-Input Toy Model from Bastos and O'Hagan (2009)
In GADGET: Gaussian Process Approximations for Designing Experiments

Description Usage Arguments Value References Examples

A toy model for the demonstration of Gaussian process validation plots and statistics. It is a product of a rational function in x[1] and an exponential function in x[2]. The function is smoother in x[2] than x[1]. The function's domain is the unit square.

1	bo09_toy(x)

`x`	A vector of length 2.

A scalar.

Bastos, L. S., & O'Hagan, A. (2009). Diagnostics for gaussian process emulators. Technometrics, 51(4), 425–438, <doi:10.1198/TECH.2009.08019>.

print(bo09_toy(c(0.5,0.25)))

n <- 100
a <- seq(0,1,length.out = n)
x <- expand.grid(a,a)
z <- matrix(apply(x,1,bo09_toy),n,n)
graphics::contour(a,a,z, xlab = expression(x[1]), ylab = expression(x[2]))