UPDATE WITH NOMINAL CENTERING (UCδ) D1.0 (UCδ types) The set of UCδ types Θ is the smallest set such that: i. t, δ, s ∈ Θ ii. (ab) ∈ Θ, if a, b ∈ Θ D1.1 (UCδ basic terms). For each a ∈ Θ, a set of a-constants Cona and a-variables Vara, incl.: Conδ = {a, b, c} Var(sδ) = {x, y, z}