  We propose a method to assess the intrinsic risk carried by a financial
position $X$ when the agent faces uncertainty about the pricing rule assigning
its present value. Our approach is inspired by a new interpretation of the
quasiconvex duality in a Knightian setting, where a family of probability
measures replaces the single reference probability and is then applied to value
financial positions.
  Diametrically, our construction of Value\&Risk measures is based on the
selection of a basket of claims to test the reliability of models. We compare a
random payoff $X$ with a given class of derivatives written on $X$ , and use
these derivatives to \textquotedblleft test\textquotedblright\ the pricing
measures.
  We further introduce and study a general class of Value\&Risk measures $%
R(p,X,\mathbb{P})$ that describes the additional capital that is required to
make $X$ acceptable under a probability $\mathbb{P}$ and given the initial
price $p$ paid to acquire $X$.
