“…Metrics of optimality other than the EIG are also possible [9,20,120], with the BED framework more generally referring to any approach that optimizes an objective of the form E p(θ)p(y|θ,ξ) [U (ξ, θ, y)] for some utility, U , that is a functional of the posterior, p(θ|y, ξ) (with some authors further relaxing this constraint on the form of U ). For example, the notion of an expected Fisher information gain has also recently been considered [104,111,138,144] because it can be easily estimated without evaluating either the posterior or marginal likelihood. Our focus, though, will be on maximizing the EIG defined in (2), as this remains the most commonly used information-theoretic BED approach; we implicitly refer to this specific approach when using the term BED in the rest of the paper.…”