Modern generative models are roughly divided into two main categories: (1) models that can produce high-quality random samples, but cannot estimate the exact density of new data points and (2) those that provide exact density estimation, at the expense of sample quality and compactness of the latent space. In this work we propose LED, a new generative model closely related to GANs, that allows not only efficient sampling but also efficient density estimation. By maximizing log-likelihood on the output of the discriminator, we arrive at an alternative adversarial optimization objective that encourages generated data diversity. This formulation provides insights into the relationships between several popular generative models. Additionally, we construct a flow-based generator that can compute exact probabilities for generated samples, while allowing low-dimensional latent variables as input. Our experimental results, on various datasets, show that our density estimator produces accurate estimates, while retaining good quality in the generated samples.

本研究提出了一种新的生成模型LED，它不仅可以高效地生成样本，还可以进行高效的密度估计，并通过最大化判别器输出的对数似然来鼓励生成数据的多样性，同时构建一个流式生成器，在保持良好的生成质量的同时，可以计算生成样本的准确概率。

基于潜变量的密度估计