Fast Flexible Space-Filling Designs for Nonrectangular Regions

Space‐filling designs allow for exploration of responses with many different settings for each input factor. While much research has been done using rectangular design spaces, it is not uncommon to have constraints on the design region where some combinations are impossible or undesirable to run. In this article, we present an intuitive method for quickly generating space‐filling designs that have the flexibility to accommodate nonrectangular design regions. We also show that these designs perform favorably compared with other standard designs with respect to the average distance of an arbitrary point in space to the closest design point. This property holds even when the design region is rectangular.