On Wed, May 19, 2010 at 3:38 PM, Peter Zbornik <[email protected]> wrote: > Frank, just one comment: Vote management is very common in our party. And > yes, we have voters often split up in groups, or factions.
"Vote management" has a specific meaning in terms of PR-STV. It is possible that a faction that has 1.7 quotas can get 2 seats by having their supporters split their votes evenly between the 2 candidates. This means that they both get 0.85 quotas each. There is a good chance that neither of them will be eliminated and they will get elected in the last round. It also works where a faction has 1 candidate who is popular with the voters outside the faction. The faction might decide not to vote for him, since he will be elected anyway, so they don't want to waste their votes. They can then use their votes to elect someone else from the faction. Having said that, Schulze's PR method is specifically designed to guard against these types of strategies. Meek's method, which is slightly less complex, also protects against one of these strategies. If you are using Schulze's method, then I don't think this is an issue. Each voter might as well just vote honestly. The wikipedia page on Schulze STV shows an example of free riding. http://en.wikipedia.org/wiki/Schulze_STV Also, vote management from other factions can't prevent a faction from getting a seat that it is entitled to. If a faction has 1.2 quotas worth of votes, then it is guaranteed to get at least 1 seat. It normally effects the last 1-2 seats that are filled as, in basic PR-STV, they can be filled without those candidates reaching the quota. ---- Election-Methods mailing list - see http://electorama.com/em for list info
