Let $\mathfrak{X}$ be a strongly nondegenerate polystable formal scheme with associated skeleton $\Delta$ and $\tau$ an open face of $\Delta$. A function $h:\tau\rightarrow\mathbb{R}$ is called convex if there exists a surjective étale morphism $\varphi:\mathfrak{X}^{\prime}\rightarrow\mathfrak{X}$ with a strongly nondegenerate strictly polystable formal scheme $\mathfrak{X}^{\prime}$ and an open face $\tau^{\prime}$ of the skeleton associated to $\mathfrak{X}^{\prime}$ with $\varphi^{\textup{an}}(\tau^{\prime})=\tau$ such that $h\circ\varphi^{\textup{an}}:\tau^{\prime}\rightarrow\mathbb{R}$ is convex. For such a convex function $h$ on $\tau$ we define $\MA(h):=\left(\varphi^{\textup{an}}\Big|_{p_{\mathfrak{X}^{\prime}}^{-1}(\tau^{\prime})}\right)_{\ast}\MA\left(h\circ\varphi^{\textup{an}}\Big|_{\tau^{\prime}}\right)$. It will follow from Corollary 5.10 that this is independent of the choices.