the problem that we're sampling from the generator when we want to sample from the discriminator by setting f of X to be P data over P generator and this means that we'll have kind of bad variance in our samples because we're sampling from the generator and then rewriting everything to make it look like we sampled from the discriminator but in theory this is unbiased from there it takes a little bit of algebra to figure out exactly how we should take the discriminator and implement this ratio we recall that the optimal