data that must be targeted to understand, plan and act in a
predictive way. This perspective raises new questions about
the quality of the data. In this context, people do not agree
with the definition of quality. The quality of the data may
be its high processing level or its relevance according to the
reality they represent. In fact, since Big Data is big and messy,
challenges can be classified into engineering tasks (managing
data at an unimaginable scale) and semantics (finding and
meaningfully combining information that is relevant to your
needs) [36] have identified each a relevant challenge for Big
Data: