Before revision:  Using just ten minutes of labeled data and pre-training on 53k hours of unlabeled data still achieves 5.2 / 8.6 WERon the noisy/clean test sets of Librispeech .
After revision:  Using just ten minutes of labeled data and pre-training on 53k hours of unlabeled data still achieves 5.2 / 8.2 WER .