stepEdgeParSelLL2K {DRIP} | R Documentation |
edge detection, parameter selection
Description
Select threshold value for LL2K edge detector using bootstrap procedure
Usage
stepEdgeParSelLL2K(image, bandwidth, thresh, nboot)
Arguments
image |
A square matrix object of size n by n, no missing value allowed. |
bandwidth |
Positive integers to specify the number of pixels used in the local smoothing. These are the bandwidth parameters to be chosen from. |
thresh |
Threshold values to be chosen from. |
nboot |
Number of bootstrap samples. |
Details
A jump-preserving local linear kernel smoothing is applied to estimate the
discontinuous regression surface; Bootstrap samples are obtained by
drawing with replacement from the residuals and the d_{KQ}
is computed
for the detected edges of the original sample and those of the bootstrap
samples.
Value
Returns a list of the selected bandwdith, the selected
threshold value, and a matrix of d_{KQ}
values with each entry
corresponding to each combination of bandwdith and threshold.
References
Kang, Y., and Qiu, P., "Jump Detection in Blurred Regression Surfaces," Technometrics, 56, 2014, 539-550.
See Also
stepEdgeParSelLCK
, stepEdgeParSelLLK
,
stepEdgeParSelLC2K
, stepEdgeLL2K
Examples
data(sar) # SAR image is bundled with the package and it is a
# standard test image in statistics literature.
set.seed(24)
parSel <- stepEdgeParSelLL2K(image = sar, bandwidth = 5, thresh = 20:21, nboot = 1) # Time consuming