# 識別モデル(discriminative model)と生成モデル(generative model)

• Generative models can generate new data instances.
• Discriminative models discriminate between different kinds of data instances.

More formally, given a set of data instances X and a set of labels Y:

• Generative models capture the joint probability $p(X, Y)$, or just $p(X)$ if there are no labels.
• Discriminative models capture the conditional probability $p(Y | X)$.