The contextual and multilevel analysis have been improved with the use of data that permit to introduce different aggregation levels in a physical space or in a more abstract one (classes, schools, enterprises x) in different social and economic contexts. The Norwegian Statistical Services permitted me to use data from their population register: they give children’s date of birth and migration’s dates of a number of generations, with different individual characteristics. They permitted the practical application of these methods to exhaustive data. The different results from this work throw light in a very interesting way on the different aggregation levels and permit a better understanding of their respective working. They also show the contradictions observed while working separately at different aggregation levels.