We consider the super-hedging price of an American option in a discrete-timemarket in which stocks are available for dynamic trading and European optionsare available for static trading. We show that the super-hedging price $\pi$ isgiven by the supremum over the prices of the American option under randomizedmodels. That is, $\pi=\sup_{(c_i,Q_i)_i}\sum_ic_i\phi^{Q_i}$, where $c_i \in\mathbb{R}_+$ and the martingale measure $Q^i$ are chosen such that $\sum_ic_i=1$ and $\sum_i c_iQ_i$ prices the European options correctly, and$\phi^{Q_i}$ is the price of the American option under the model $Q_i$. Ourresult generalizes the example given in ArXiv:1604.02274 that the highest modelbased price can be considered as a randomization over models.
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