Originally Posted by
chriswufgator
Sure I do, they've admitted what they were doing. Not exactly a secret anymore.
This is not responsive to what I was talking about.
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Again, there is really no way to know based solely on transactional data (which is all Amex has available to them) whether any potential correlations are real or merely coincidence.
This is not all they have available to them. They also have available to them which cardmembers are in default. These data together are good enough to build up extremely useful patterns.