Variance Dispersion Graphs and Fraction of Design Space Plots
Description
Facilities for constructing variance dispersion graphs, fraction-of-design-space plots
and similar graphics for exploring the properties of experimental designs. The design region is
explored via random sampling, which allows for more flexibility than traditional variance
dispersion graphs. A formula interface is leveraged to provide access to complex model
formulae. Graphics can be constructed simultaneously for multiple experimental designs and/or
multiple model formulae. Instead of using pointwise optimization to find the minimum and
maximum scaled prediction variance curves, which can be inaccurate and time consuming, this
package uses quantile regression as an alternative.