Papers › On the Generative Utility of Cyclic Conditionals

On the Generative Utility of Cyclic Conditionals

30 Jun 2021NeurIPS 2021 12arXiv:2106.15962archive 2025-07-28

Chang Liu, Haoyue Tang, Tao Qin, Jintao Wang, Tie-Yan Liu

We study whether and how can we model a joint distribution p(x,z) using two conditional models p(x|z) and q(z|x) that form a cycle. This is motivated by the observation that deep generative models, in addition to a likelihood model p(x|z), often also use an inference model q(z|x) for extracting representation, but they rely on a usually uninformative prior distribution p(z) to define a joint distribution, which may render problems like posterior collapse and manifold mismatch. To explore the possibility to model a joint distribution using only p(x|z) and q(z|x), we study their compatibility and determinacy, corresponding to the existence and uniqueness of a joint distribution whose conditional distributions coincide with them. We develop a general theory for operable equivalence criteria for compatibility, and sufficient conditions for determinacy. Based on the theory, we propose a novel generative modeling framework CyGen that only uses the two cyclic conditional models. We develop methods to achieve compatibility and determinacy, and to use the conditional models to fit and generate data. With the prior constraint removed, CyGen better fits data and captures more representative features, supported by both synthetic and real-world experiments.

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CyGen changliu00/cygen/methods/cygen.py official repository ran MIT (permissive) · e84b055f469eaec5 · report
SampleGradContainer changliu00/cygen/methods/cygen.py official repository ran MIT (permissive) · 6e8e63560e1504bd · report
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smart_grad changliu00/cygen/methods/cygen.py official repository ran · fixture could not drive it MIT (permissive) · 6b8b7358fd0a9717 · report
track_var changliu00/cygen/methods/cygen.py official repository ran · fixture could not drive it fingerprinted MIT (permissive) · a2feae0e8bfc2fd1 · report
track_var changliu00/cygen/methods/cygen.py official repository ran · fixture could not drive it fingerprinted MIT (permissive) · f76225cb9e3de0b7 · report
smart_grad changliu00/cygen/methods/cygen.py official repository unverified MIT (permissive) · 6a6067ace5950671 · report
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