Three-Steps Procedure for the Analysis of Ecological Data: a Case Study

For the study of pollution bio-indicators, based on a sampling of Pinus pinea L. leaves in three differently polluted sites performed in nine different occasions, the indicators were submitted to a three-step procedure that started from exploratory analysis, through confirmatory analysis, to the modelling of the behaviour of the indicators along time. In this way, a deeper understanding of the data led to a better interpretation of the results and a more suitable model building. It is interesting to put in evidence that most of the data analysis methods used for this work are based on optimization of some objective function.