\delta \left( \mathcal{Q}_{\ll }\left( \mathbb{P}\right) \right) :=\left\{ Z\in L^{0}\left( \mathbb{P}\right) :Z=d\mathbb{Q}/d\mathbb{P}\text{ with }\mathbb{Q}\in \mathcal{Q}_{\ll }\left( \mathbb{P}\right) \right