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@krischik StackOverflow is a very specific niche community, so its peers evaluating eachother (a sort of qualified vote.

On an universal social blockchain, you have people interested on arts affecting people interested on tech, mutually contributing to the reputation. Maybe that's the reason why a reputation system for a universal social blockchain is quite a problem. @blocktrades is working on such a system, but I suspect is a higher level of complexity than using models that work on specific subject oriented communities.