Verifiers
Another key technique for improving task performance is to train a verifier or discriminator model to evaluate the outputs of the main generative model. If the discriminator rejects the output, then you can resample the generative model until you get an acceptable output. In many cases, it's easier to judge an answer than it is to create an answer, which helps explain the power of this method.

Method
In 2021, OpenAI researchers applied this technique to grade school math problems, using the following procedure: