How reputation systems work is an important issue. I hope we can discuss it further. At 10:32 PM 9/10/95, Wei Dai wrote:
In an economy based on positive reputations, how does one acquire a reputation capital? One way may be to initially perform services at a price below cost, but this has some problems.
For example, Alice starts a anonymous consulting service, and announces that she will answer the first ten queries for free. Upon hearing this, Mallet immediately starts another consulting service, and announces the same offer. At this point Mallet can simply forward his customers' queries to Alice and Alice's answers back to his customers. Thus, he gains reputation at no cost.
On the other hand, this "man-in-the-middle" attack can also work against conventional True Name based services, but perhaps with less effect. Has anyone ever heard of this being done?
This line of reasoning is a variant of the "Chess Grandmaster" scheme, wherein one gains the reputation of a chess grandmaster by echoing the moves of a chess grandmaster playing in another game. I believe this is described in various crypto books, but I haven't looked it up here. In practice, nothing so simple as an "Ask any 10 questions" would be a practical way to gain reputation. If Alice is trying to build up a rep, she'll choose her customers with some care, or make sure that alternate channels also exist.
Is there a better way to acquire a good reputation?
Directly contacting a larger group, such as this list, is usually a faster and better way to build a reputation than in, say, answering only questions directly made. Admittedly, many consulting cases involve direct contacts. However, the reputation of a Pr0duct Cypher, or a Black Unicorn, or a Tim May, or a Wei Dai, is usually made in a public forum, not primarily in one-on-one contacts. While not all of us sign our posts, the principal is roughly the same: we are communicating directly, so man-in-the-middle attacks, or "Chess Grandmaster" attacks, are fairly ineffective. And practically speaking, if someone hires _me_ as a consultant, it is probably based on past achievements, through multiple channels. This would apply to digital pseudonyms as well, though not as directly. (Humorous Sidenote: an informal variant of the Chess Grandmaster approach is to use the best arguments found on one list on _another_ list. Another variant, widely used, is to adopt the best arguments of others and use them one's self (oneself?). This is how memes spread, and is central to the advancement of knowledge.) --Tim May ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay@got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 | black markets, collapse of governments. "National borders are just speed bumps on the information superhighway."