Before revision: We say that is a garbling of if there exists a Stochastic matrix such that Intuitively, garbling is a way of adding "noise" to an information structure .
After revision: We say that is a garbling of if there exists a stochastic map (for finite signal spaces , a Markov matrix), such that the garbled information structure is considered to be less informative such that Intuitively, garbling is a way of adding "noise" to an information structure .