Let m and l~ be natural numbers with m≥1 and l~≥1, let T>0 be a real number, and let A be a nonempty subset of Euclidean space Rm. Let h=(hk)k≥0 be an observation-driven control policy with horizon T, control dimension m and l~ channels, and let Rk(T) be the record spaces of that definition.
The policy h is A-valued if
h0(t)∈Afor every t∈[0,T],
and, for every natural number k≥1,
hk(t,τ,v)∈Afor every t∈[0,T], τ∈Rk(T) and v∈{1,…,l~}k.