“…Here ℓ( χψ , ψ; χ, ψ, a) and j χχ ( χψ , ψ; χ, ψ, a) are the log likelihood function and the observed information for χ respectively. They depend on the data only through the minimal sufficient statistic [(Da Silva, Ferrari, & Cribari-Neto, 2008)]. An alternative formula for (4), which is obtained through approximating ancillary statistic is given by…”