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[Soft-deprecated] Generates a distribution definition when only parameter estimates are available for gamma distributed parameters. See rgamma() for distribution information.

Usage

gamma_dist_def(
  shape,
  shape_sd,
  scale,
  scale_sd,
  mean,
  mean_sd,
  sd,
  sd_sd,
  max_value,
  samples
)

Arguments

shape

Numeric, shape parameter of the gamma distribution.

shape_sd

Numeric, standard deviation of the shape parameter.

scale

Numeric, scale parameter of the gamma distribution.

scale_sd

Numeric, standard deviation of the scale parameter.

mean

Numeric, log mean parameter of the gamma distribution.

mean_sd

Numeric, standard deviation of the log mean parameter.

sd

Numeric, log sd parameter of the gamma distribution.

sd_sd

Numeric, standard deviation of the log sd parameter.

max_value

Numeric, the maximum value to allow. Defaults to 120. Samples outside of this range are resampled.

samples

Numeric, number of sample distributions to generate.

Value

A <data.table> defining the distribution as used by dist_skel()

Author

Sam Abbott

Examples

# using estimated shape and scale
def <- gamma_dist_def(
  shape = 5.807, shape_sd = 0.2,
  scale = 0.9, scale_sd = 0.05,
  max_value = 20, samples = 10
)
print(def)
#>      model    params max_value
#>     <char>    <list>     <num>
#>  1:  gamma <list[2]>        20
#>  2:  gamma <list[2]>        20
#>  3:  gamma <list[2]>        20
#>  4:  gamma <list[2]>        20
#>  5:  gamma <list[2]>        20
#>  6:  gamma <list[2]>        20
#>  7:  gamma <list[2]>        20
#>  8:  gamma <list[2]>        20
#>  9:  gamma <list[2]>        20
#> 10:  gamma <list[2]>        20
def$params[[1]]
#> $shape
#> [1] 5.978225
#> 
#> $scale
#> [1] 1.103153
#> 

# using mean and sd
def <- gamma_dist_def(
  mean = 3, mean_sd = 0.5,
  sd = 3, sd_sd = 0.1,
  max_value = 20, samples = 10
)
print(def)
#>      model    params max_value
#>     <char>    <list>     <num>
#>  1:  gamma <list[2]>        20
#>  2:  gamma <list[2]>        20
#>  3:  gamma <list[2]>        20
#>  4:  gamma <list[2]>        20
#>  5:  gamma <list[2]>        20
#>  6:  gamma <list[2]>        20
#>  7:  gamma <list[2]>        20
#>  8:  gamma <list[2]>        20
#>  9:  gamma <list[2]>        20
#> 10:  gamma <list[2]>        20
def$params[[1]]
#> $shape
#> [1] 1.405135
#> 
#> $scale
#> [1] 0.4081698
#>