Detect bounds for density function

Manual detection of bounds of parameter of a density function/

Usage

detectbound(distname, vstart, obs, fix.arg=NULL, echo=FALSE)

Arguments

distname

A character string "name" naming a distribution for which the corresponding density function dname must be classically defined.

vstart

A named vector giving the initial values of parameters of the named distribution.

obs

A numeric vector for non censored data.

fix.arg

An optional named vector giving the values of fixed parameters of the named distribution. Default to NULL.

echo

A logical to show some traces.

Details

This function manually tests the following bounds : -1, 0, and 1.

Value

detectbound returns a 2-row matrix with the lower bounds in the first row and the upper bounds in the second row.

See also

fitdist.

References

Delignette-Muller ML and Dutang C (2015), fitdistrplus: An R Package for Fitting Distributions. Journal of Statistical Software, 64(4), 1-34, doi:10.18637/jss.v064.i04 .

Author

Christophe Dutang and Marie-Laure Delignette-Muller.

Examples

# case where the density returns a Not-an-Numeric value.
detectbound("exp", c(rate=3), 1:10)
#>      rate
#> lowb    0
#> uppb  Inf
detectbound("binom", c(size=3, prob=1/2), 1:10)
#>      size prob
#> lowb -Inf    0
#> uppb  Inf    1
detectbound("nbinom", c(size=3, prob=1/2), 1:10)
#>      size prob   mu
#> lowb    0    0 -Inf
#> uppb  Inf    1  Inf