[erikig]

I got firsthand experience of this as well. We built a system that leveraged Bayesian filtering for risk measurement and transaction approval (above and beyond CVC and AVS) in high risk markets.

When things were going well, they were great but when they weren't it was really bad. In short, card issuers tend to side with clients (card holders_ and even with the best risk management, it is not an easy business to get right.