tests/testthat/test_00_SICHEL.R

In Stan125/gamlss.dist: Distributions for Generalized Additive Models for Location Scale and Shape

################################
####       gamlss.dist      ####
####   Distribution tests   ####
####    Sichel: SICHEL()    ####
################################

## Context
testthat::context("SICHEL")

## Seed
set.seed(178)

## Family
fam <- SICHEL()

## Random Values
n <- 1e4
mu <- 1
sigma <- 1
nu <- -0.5
rvec <- rSICHEL(n, mu, sigma, nu) 

## Empirical Moments
ex_emp <- mean(rvec)
vx_emp <- var(rvec)

## Theoretical moments
ex_theo <- fam$mean(mu, sigma, nu)
vx_theo <- fam$variance(mu, sigma, nu)

## Test here if they are about the same
expect_true(abs(ex_emp - ex_theo) < 0.02)  
expect_true(abs(vx_emp - vx_theo) < 0.02)  # not robust