[ctrw]

I tried building a reddit style baord using that. The main issue became that calculating weights was more expensive than everything else combined. At one extreme you have the trust matrix which you just multiply with itself to get the nth hop scores, at the other you had the linked list graph traversal. Neither were good solutions.

With how much matrix multiplication were doing for machine learning using the matrix approach now might be feasible.

[simcop2387]

That might work nicely with a lot of the sparse matrix research going on too, since I suspect that the trust matrix should be very sparse

[zizee]

If I am understanding correctly, did you consider the option of calculating weights in the client?

[ctrw]

I would be leaking all social graph data and all voting data to each person using the service. So it's a no go from the start.

[TeMPOraL]

The problem description sounds vaguely PageRank-y, so maybe similar trick can be applied?