Here I'll describe the process of trust aggregation, and discuss what might happen if it was used (how it might be useful, along with concerns).
It's something I would want to include in my dream website.
How it works
It works fairly simply. Something like this:
- Everyone lists everyone they know, and records how much (a percent) they trust each of them.
- Using all of these lists, computations can be done to estimate how much someone might be able to trust a person they had never met (or heard of) before.
So how does that step #2 work? What are the computations? What are the limitations?
The computation requires an unbroken chain of evaluations between the user and the person they want an estimation for. Basically, the computation involves multiplying the percent trust scores together along the chain, and getting a result. (Of course, sometimes there are multiple paths that have to be handled)
I have created a simple program to do this, just to prove to myself that it worked the way I expected.
A more advanced version would record more types of evaluations and such. For example "how likely is this person to be on time?", or any other kinds of behavior. A very important metric for the "aggregation" part of "trust aggregation" would be how much you trust someone to evaluate others correctly. If they are good at knowing who to trust, then they have done some work for you. It's a division of labor, many hands make light work.
What happens if we use it?
So long as this whole idea is useful, it seems likely that specialized large-scale aggregators will emerge. That is, there will be people (or groups) who try to be your #1 source for estimates. They will try to make you trust themselves as much as possible, so that you trust their evaluations as much as possible. That will put pressure on everyone who wants good reviews, and they will try to ensure they are in good standing.
Different aggregators will disagree with each other. Think of any contentious political issue. Is someone bad if they are in favor of abortion? Is someone bad if they voted for Trump? Some people think so, some people think the opposite is true. What will happen? Will trust aggregation make these conflicts worse, or better?
Will you just have an echo chamber?
I don't think so. The trust scores you'd see wouldn't necessarily come as you would expect. Sometimes a smart person you trust says something you wouldn't have believed if it had come from a stranger. A trusted friend might even disagree with you. They may be right or wrong, but they are definitely different than you are, to some degree.
But those examples are from our present world. Would echo chambers emerge if trust aggregation was widely used for a long enough time? Or would the whole world become more (and more?) unified together? Or no change positive or negative?
I suspect it would tend towards an equilibrium of higher and higher trustworthiness.