Trust graphs aren't commonly used. More commonly blackbox global reputation systems are used.
I'm going to be giving a talk on Web of Trust soon and will be revisiting some of my research so I'll try to remember to come back and drop some links. Most of the existing research is provided in the context of public key infrastructure (pki) and p2p networks.
I gave a high level overview of WoT in this workshop:
Awesome thanks @k00b. Maybe we need a remind-me bot on here for use cases like this ☺️
Will share here too if I find anything of interest. Or perhaps create a dedicated post with findings.
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