Before revision:  We illustrate this approach on several physical problems , such as the Burgers', Korteweg-de Vries , advection-diffusion and Keller-Segel equations, and find that it requires as few as O (10^2) samples and works at noise levels up to 75 \%.
After revision:  We illustrate this approach on several physical problems , such as the Burgers', Korteweg-de Vries , advection-diffusion and Keller-Segel equations, and find that it requires as few as \mathcal{O (10^2) samples and works at noise levels up to 75 \%.