I’ve heard that credit card companies know when you’re cheating or about to get divorced. I’d imagine things like flowers, gifts and hotels would be a tip off, but general expenses probably approach double once a couple is separated.
This data about facebook posts makes perfect sense too. People using FB will post more flirtatiously until the relationship starts. But after, why post so much? Even in real life, it’s rare for couples to make strong public displays of affection once they’re together. If they do, it may come more from insecurity about the relationship, or insensitivity to others’ feelings, than from some unparalleled eternal flame.
This highlights one of Facebook’s core challenges — how to capture sentiments shared between people who spend a lot of time together.