getRiceParam {shotGroups} | R Documentation |
Estimate Rice parameters nu and sigma
Description
Estimates the location parameter nu and the scale parameter sigma of the Rice distribution together with the radial mean MR and radial standard deviation RSD based on a set of 2D-coordinates. Includes the parametric confidence interval for sigma.
Usage
getRiceParam(xy, level = 0.95, doRob = FALSE, type = c('LiZhangDai', 'MOM'))
## S3 method for class 'data.frame'
getRiceParam(xy, level = 0.95, doRob = FALSE, type=c('LiZhangDai', 'MOM'))
## Default S3 method:
getRiceParam(xy, level = 0.95, doRob = FALSE, type=c("LiZhangDai", 'MOM'))
Arguments
xy |
either a numerical (n x 2)-matrix with the (x,y)-coordinates of n points (1 row of coordinates per point), or a data frame with either the variables |
level |
a numerical value with the coverage for the confidence interval for sigma. |
doRob |
logical: use robust estimation of center and covariance matrix as basis for estimators? |
type |
The initial biased nu estimate is the Euclidean norm of the group center. For |
Details
The sigma estimate uses getRayParam
. The robust estimate for the center and for the covariance matrix of (x,y,z)-coordinates is from covMcd
using the MCD algorithm.
Value
A list with the estimates for nu, sigma, RSD, and MR including the confidence interval for sigma.
nu |
The estimated location parameter nu. |
sigma |
A vector with the sigma estimate and confidence interval bounds as named elements |
MR |
The MR estimate. |
RSD |
The RSD estimate. |
References
https://reference.wolfram.com/language/ref/RiceDistribution.html
Li, Q., Zhang, J., & Dai, S. (2009). On estimating the non-centrality parameter of a chi-squared distribution. Statistics and Probability Letters 79, 98-114.
See Also
Rice
,
getRayParam
,
getCEP
,
getHitProb
,
covMcd
Examples
getRiceParam(DF300BLKhl, level=0.95, doRob=FALSE)
# coordinates given by a matrix
## Not run:
xy <- matrix(round(rnorm(60, 0, 5), 2), ncol=2)
getRiceParam(xy, level=0.95, doRob=FALSE)
## End(Not run)