Differentially private learning on real-world data poses challenges for
standard machine learning practice: privacy guarantees are difficult to
interpret, hyperparameter tuning on private data reduces the privacy budget,
and ad-hoc privacy attacks are often required to test model privacy. We
introduce three tools to make differentially private machine learning more
practical: (1) simple sanity checks which can be carried out in a centralized
manner before training, (2) an adaptive clipping bound to reduce the effective
number of tuneable privacy parameters, and (3) we show that large-batch
training improves model performance.