I am highly suspicious of any system that requires voting to make a decision. In very few cases have I seen that voting cannot be simplified out of the decisionmaking process with substantial benefit to all involved.
Many think that voting is the way to minimize the number of dis-satisfied people. But very few actual voting systems come anywhere close to actually achieving that goal.
From an FC point of view, voting is a more difficult problem than payment, which also indicates that it is a costy endeavor and one has to think twice before going forward with a voting.
Moreover, the more pepole vote, the less sense it makes, given the large transaction costs (the more complicated the system is, the more voters you lose).
Think about it this way: one places a certain value on one outcome versus the other (in the binary case, which is trivial to generalize). Then one calculates the probability that his/her vote will decide the outcome (decays roughly with the square root of the number of voters). The product of these two is the (expected) benefit from voting. If the (transaction) cost of voting exceeds this value (as is almost always the case in political votes), it is irrational to vote, which is why rational people (like myself :-)) abstain from voting in places where it is not compulsory. One consequence of this is that if the preferences are strongly correlated with the rationality, it is the choice preferred by irrational people that is going to win the vote (which still does NOT make it rational to vote; think about it).
Voting is only rational when the stake is large and the number of voters small.
Also, voting is very sensitive to all nuances in the rules. Take, for example, the latest general elections in Hungary: the barrier for a party to enter the parliament is 5%. Given the same votes, the current opposition would be in power if this paramenter would have been either 4% or 6%. So go figure.
Weighed voting is another nightmare. For a long time, Luxemburg had exactly zero say in the European Comission. Here's a small example:
Alice and Bob have 4 votes, Claire has 2 and Daniel has only 1. In this setting, the binary issues are determined by the majority of Alice, Bob and Claire, while Daniel's vote doesn't affect the outcome.
Most voting systems are riddled with flaws of this kind, and even those that are not do a very poor job at decision-making.
I guess, my comment can be summed up like this:
Designing a good voting system is much more difficult than designing a good payment system (which is difficult enough), and very probably not worth the effort. Tossing a coin is a preferable alternative in a surprisingly large number of cases.
Electronic voting is perhaps the hardest discipline of financial cryptography. It's a very good way to teach and learn it, but there are very few justified applications. I don't know of any.
I agree with most of that. There are a couple of caveats here. Firstly, the group has decided to do voting, or been chartered to do voting, and that's that. Many of the things that you point out came out in the design discussions and they remain barriers to cross.
One of the things that was apparent was that delegated voting is much harder, and takes us into territory where computing is needed. I suggested they do direct voting in the first instance, and leave delegated voting for another day. Given the efficiency argument though it is going to be essential for a real application.
Surprisingly, they also went for non-anonymous voting, which I think is only used where accountability is important.
As to whether you can economise it out in all cases, I think this is hopeful. Many structures have mandated voting requirements, and those will stay for a long time. For this reason, I'll be adding voting to Ricardo and XML-X at some stage, but at least in that environment the side issues such as authentication are solved, and the only question is what the best voting mechanism is. My view there is gradually migrating to "all of them" and some sort of smart contracts voting.
Posted by Iang at August 19, 2005 02:43 AM