space_removal {hmer}

Percentage of Space Removed

Description

For a wave of emulators, estimates the proportion of space removed at this wave.

Usage

space_removal(
  ems,
  targets,
  points = NULL,
  ppd = NULL,
  cutoff = 3,
  individual = TRUE
)

Arguments

ems

The emulators to compute over, as a list

targets

The output target values

points

The points to test against

ppd

If no points are provided and uniform grid is wanted, the number of points per parameter dimension.

cutoff

The cutoff value for implausibility

individual

If true, gives emulator-by-emulator results; otherwise works with maximum implausibility

Details

Given a collection of emulators corresponding to a wave, we can look at an estimate of the proportion of points from previous waves that will be accepted at this wave, either on an emulator-by-emulator basis (to see which outputs are most restrictive) or as an all-wave determination.

Naturally, such a statement will be an estimate of the restriction on the full space (which will become more unreliable for higher dimensions), but it can give an order-of-magnitude statement, or useful comparators between different emulators in a wave.

If no points are provided, the training points for the emulators are used. For best results, a good number of points should be given: typically one should consider using as many points as one knows to be in the NROY space (including any validation points, if accessible).

Value

A numeric corresponding to the proportions of points removed.

See Also

space_removed for a visualisation of the space removal.

Examples

 space_removal(SIREmulators$ems, SIREmulators$targets,
  rbind(SIRSample$training, SIRSample$validation))
 space_removal(SIREmulators$ems, SIREmulators$targets,
  rbind(SIRSample$training, SIRSample$validation), individual = FALSE)