Introduction

Before beginning the study of Statistics, it is relevant to characterize the scope

of the area and the main issues involved in this study. We avoid directly defin-

ing the subject, which is a hard and polemical task. Some of the components

involved in this area of science will be presented in the hope that at the end

the reader will have a clear notion of the broadness of the subject under con-

sideration. The fundamental problem towards which the study of Statistics is

addressed is that where randomness is present. The statistical methodology to

deal with the resulting uncertainty is based on the elaboration of probabilistic

models in order to summarize the relevant information available.