Task: Question Generation
Input (English): Given a proof state $= (_, _)$ , where $_$ and $_$ denote a substitution set and a proof score, respectively, unification is computed as follows: The resulting proof score of $g$ is given by:

$$ \begin{aligned} \max _{f \in \mathcal {K}} & \; {unify}_(g, [f_{p}, f_{s}, f_{o}], (\emptyset , )) \\ & = \max _{f \in \mathcal {K}} \; \min \big \lbrace , \operatorname{k}(_{\scriptsize {grandpaOf}:}, _{f_{p}:}),\\ &\qquad \qquad \qquad \operatorname{k}(_{{abe}:}, _{f_{s}:}), \operatorname{k}(_{{bart}:}, _{f_{o}:}) \big \rbrace , \end{aligned}$$ (Eq. 3)

where $f \triangleq [f_{p}, f_{s}, f_{o}]$ is a fact in $\mathcal {K}$ denoting a relationship of type $f_{p}$ between $f_{s}$ and $f_{o}$ , $_{s:}$ is the embedding representation of a symbol $s$ , $$ denotes the initial proof score, and $\operatorname{k}({}\cdot {}, {}\cdot {})$ denotes the RBF kernel.
Output (English): How are proof scores calculated?