While not pure arbitrage, Forex statistical arbitrage uses a quantitative approach to identify price divergences that are statistically likely to occur in the future.

A basket of outperformers and a basket of underperformers are collected. The basket is constructed with the intention of shorting outperformers and buying underperformers.

Eventually, the relative worth of one basket compared to another will revert to the mean. It would be desirable for the two baskets to have a strong historical connection. This is another consideration that the arbitrator must make when creating the initial picks. Additionally, you want to maximize market neutrality.