<title>Abstract</title> The definition of robustness in econometrics, the error term in a linear equation, was not only broadened, but, in addition, moved to the meaning of common language: from a cardinal to a qualitative one: the most robust one, more robust than…, as robust as……, robust, weak robust,...

<title>Abstract</title> Construction, taking off, maintenance and facilities management of a building is a typical example of consumer sovereignty: the new owner likes to have a reasonable price to pay, to have confidence in the contractor, to know about the duration of the works, the service after completion...