Fit Frechet-Weibull distribution to non-censored data

Fit Frechet-Weibull distribution to non-censored data

fitdist_fr_wei(x, param_fr_wei = params_fr_wei(), method = "mle",
  optim.method = "Nelder-Mead", log = FALSE, verbose = FALSE, ...)

Arguments

x	numeric vector
param_fr_wei	data.frame of parameter bounds, output from params_fr_wei(), which defines the start, upper, and lower bounds for each of the five parameters.
method	fitting method, argument passed to fitdistrplus::fitdist().
optim.method	character method argument passed to fitdistrplus::mledist or corresponding function based upon the method argument, but ultimately passed to stats::optim().
verbose	logical indicating whether to print verbose output.
...	additional arguments are passed to fitdistrplus::fitdist().

Value

object of class "fitdist" described in fitdistrplus::fitdist().

Details

This function is a simple wrapper around fitdistrplus::fitdist() for the five-parameter Frechet-Weibull distribution. Most customizations are performed by the corresponding support function, for example when method="mle" the distribution fit function is fitdistrplus::mledist(), which then calls stats::optim(). Arguments are passed to these functions using ... where applicable.

TODO: This function currently expects to use method="mle" which utilizes the upper,lower,start parameters for each of the five parameters. Other methods may have different requirements which are not formally handled. In future we will evaluate and support additional methods, modifying the call to fitdistrplus::fitdist() as needed.

See also

Other SALSA distribution fit functions: dfr_wei, fitdist_fr, params_fr_wei

Examples

library(salsa);
data(oz2_numi_per_cell);
x <- oz2_numi_per_cell$count[oz2_numi_per_cell$count >= 16];
fit_fr_wei <- fitdist_fr_wei(x);
# print coefficients
print(coef(fit_fr_wei));
#>  fr_weight   fr_shape   fr_scale  wei_shape  wei_scale 
#>    0.99000    1.50000   25.24369    1.51412 1775.74196