Variance matrix for d, as per the bottom of page 1 of the supplement
Usage
Vd(D1, D2, theta, phi)
Arguments
D1
matrix of code run points
D2
matrix of observation points
theta
Parameters
phi
hyperparameters
References
M. C. Kennedy and A. O'Hagan 2001. Bayesian
calibration of computer models. Journal of the Royal Statistical
Society B, 63(3) pp425-464
M. C. Kennedy and A. O'Hagan 2001. Supplementary details on
Bayesian calibration of computer models, Internal report, University
of Sheffield. Available at http://www.shef.ac.uk/~st1ao/ps/calsup.ps
R. K. S. Hankin 2005. Introducing BACCO, an R bundle for
Bayesian analysis of computer code output, Journal of Statistical
Software, 14(16)