Many scientific phenomena are now investigated by complex computer models or codes. A computer experiment is a number of runs of the code with various inputs. A feature of many computer experiments is that the output is deterministic--rerunning the code with the same inputs gives identical observations. Often, the codes are computationally expensive to run, and a common objective of an experiment is to fit a cheaper predictor of the output to the data. Our approach is to model the deterministic output as the realization of a stochastic process, thereby providing a statistical basis for designing experiments (choosing the inputs) for efficient prediction. With this model, estimates of uncertainty of predictions are also available. Recent work in this area is reviewed, a number of applications are discussed, and we demonstrate our methodology with an example.
It is possible to obtain convergence to a $D$-optimum measure, as defined by Kiefer and Wolfowitz, by successively adding points to a given initial experimental design. The points added correspond to points of maximum variance of the usual least squares estimate of the response mean for the particular regression model at each stage. A new bound is given for the generalized variances involved and an example is worked out.
1 January 2000 in Journal of the Royal Statistical Society Series B: Statistical Methodology