Generative adversarial networks (GANs) are pow- erful generative models based on providing feed- back to a generative network via a discriminator network. However, the discriminator usually as- sesses individual samples. This prevents the dis- criminator from accessing global distributional statistics of generated samples, and often leads to mode dropping: the generator models only part of the target distribution. We propose to feed the discriminator with mixed batches of true and fake samples, and train it to predict the ratio of true samples in the batch. The latter score does not depend on the order of samples in a batch. Rather than learning this invariance, we introduce a generic permutation-invariant discriminator ar- chitecture. This architecture is provably a uni- versal approximator of all symmetric functions. Experimentally, our approach reduces mode col- lapse in GANs on two synthetic datasets, and obtains good results on the CIFAR10 and CelebA datasets, both qualitatively and quantitatively.

该研究提出了一种新的方法来减少GANs中的模式坍塌问题，即通过引入一种通用的置换不变鉴别器架构来训练一个预测混合批的真假样本比例的不变鉴别器得分来代替传统方式评估单个样本的鉴别器。实验证明，在两个合成数据集上，这种方法有效地减少了模式坍塌，而在CIFAR10和CelebA数据集上得到了良好的定性和定量结果。

混合批次和对称判别器用于GAN训练