Denoising Likelihood Score Matching for Conditional Score-based Data Generation

  title={Denoising Likelihood Score Matching for Conditional Score-based Data Generation},
  author={Chen-Hao Chao and Wei-Fang Sun and Bo Wun Cheng and Yi-Chen Lo and Chia-Che Chang and Yu-Lun Liu and Yu-Lin Chang and Chia-Ping Chen and Chun-Yi Lee},
Many existing conditional score-based data generation methods utilize Bayes’ theorem to decompose the gradients of a log posterior density into a mixture of scores. These methods facilitate the training procedure of conditional score models, as a mixture of scores can be separately estimated using a score model and a classifier. However, our analysis indicates that the training objectives for the classifier in these methods may lead to a serious score mismatch issue, which corresponds to the… 

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