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Sample gamma model(s) with parameters according to priors

sample_gamma_model.Rd

Sample gamma model(s) with parameters according to priors

Usage

sample_gamma_model(number_of_contributors, sampling_parameters, model_settings)

Arguments

number_of_contributors

Integer

sampling_parameters

List. Needs to contain:

  • min_mu. Numeric of length one.

  • max_mu. Numeric of length one.

  • min_cv. Numeric of length one.

  • max_cv. Numeric of length one.

  • degradation_shape1. Numeric of length one.

  • degradation_shape2. Numeric of length one.

model_settings

List. See gamma_model.

Value

When length(number_of_contributors)==1, a single gamma_model of class pg_model. Otherwise, a list of these.

Details

In simulation studies involving many mixed DNA profiles, one often needs to generate various samples with different model parameters. This function samples a gamma model with parameters according to prior distributions. The mean peak height parameter mu is sampled uniformly between min_mu and max_mu. Likewise, the variability parameter cv is sampled uniformly between min_cv and max_cv. The degradation slope parameter beta is sampled according to a Beta distribution with parameters degradation_shape1 and degradation_shape2.

Examples

gf <- gf_configuration()

sampling_parameters <- list(min_mu = 50., max_mu = 5e3,
                           min_cv = 0.05, max_cv = 0.35,
                           degradation_shape1 = 10, degradation_shape2 = 1)

model_no_stutter <- sample_gamma_model(number_of_contributors = 2,
                                      sampling_parameters = sampling_parameters,
                                      model_settings = gf$gamma_settings_no_stutter)

model_no_stutter$parameters
#> $model
#> [1] "gamma_model"
#> 
#> $mixture_proportions
#> [1] 0.4558031 0.5441969
#> 
#> $mu
#> [1] 1064.382
#> 
#> $cv
#> [1] 0.2620336
#> 
#> $degradation_beta
#> [1] 0.8587743 0.8587743
#> 
#> $LSAE
#>  D3S1358      vWA  D16S539   CSF1PO     TPOX     AMEL  D8S1179   D21S11 
#>        1        1        1        1        1        1        1        1 
#>   D18S51   D2S441  D19S433     TH01      FGA D22S1045   D5S818  D13S317 
#>        1        1        1        1        1        1        1        1 
#>   D7S820     SE33 D10S1248  D1S1656  D12S391  D2S1338 
#>        1        1        1        1        1        1 
#>