The learned material bias of COF m, µ m ∈ R, in eqn. 1 roughly describes the typical value of the (standardized) gas adsorption properties of COF m. Visualization of µ can give us an idea of which COFs tend to exhibit the largest and smallest values of the gas adsorption properties. bias µ m of CCOF-2 makes it a good candidate for measurements, in the absence of any other information; in the analogy of movie recommendation systems (see Box), CCOF-2 is like a movie that is widely liked.