Clause (ii) defines anchors and cognizers for higher evaluation levels, l n>0 .
anchors are defined as those sources from the previous evaluation level, s ∈ S n−1 , that are not uncommited (Uu) towards the factuality of e n−1 , which is the SIP event embedding l n (in the definition, the notation f (e, s) expresses the factuality assessment made by source s over event e).