Robust Transformation of Proportions Using the Forward Search

The aim of this work is to detect the best transformation parameters to normality when data are proportions. To this purpose we extend the forward search algorithm introduced by Atkinson and Riani (2000), and Atkinson et al. (2004) to the transformation proposed by Aranda-Ordaz (1981). The procedure, implemented by authors with R package, is applied to the analysis of a particular characteristic of Tuscany industries. The data used derive from the Italian industrial census conducted in the year 2001 by the Italian National Statistical Institute (ISTAT).