Chris Benham wrote:
The trouble is, range voting is simple. Simple enough that you can reach a pretty full understanding of what strategic range voting is. (Which is not at all trivial, but it can pretty much be done.) In contrast, a lot of Condorcet systems including Schulze are complicated. Complicated enough that making confident statements about their behavior with strtagic voters (or even undertsnading what strtagy IS) is hard.
Another problem is, you can use this to argue in favor of either side. If strategy is easy, then you can say that everybody can do it and thus the information content will be seriously degraded, leading to odd results. On the other hand, if strategy is hard, then you can say that the parties will crunch the numbers to find out what strategy will indeed work, and tell their voters to vote in this fashion, something which will unbalance power in favor of the large established groups.
On top of all of that, people don't strategize maximally. In other words, they're not perfectly rational. In some sense, that shouldn't be unexpected, since if people were rational, turnout would be extremely low (yet it isn't). However, it does muddy the waters further.
Basically, there seems to be two types of strategy. The first is that which anybody can do (exaggerating in Range) - let's call that tactical voting. The second is that which parties coordinate - let's call that vote management. The actual voting method weaknesses that are used may be the same (see Schulze's claim that vote management in STV is just coordinated Hylland free riding, for instance), or they may differ.
Perhaps one could make an argument that methods where strategy is harder to pull off is better (even if no method is strategyproof) like this: as regards tactical voting, the argument is simple - harder strategy will make it more difficult for people to figure out the optimal strategic vote. As regards vote management, parties that make too extensive plans would be faced with social disapproval from not "playing fair", therefore methods that require complex strategies would less often be exploited. The latter point depends on whether employing strategy is frowned upon or accepted -- one may see an example in that when New York used STV, the Republican and Democratic parties used as much vote management as they could muster, whereas in other countries, vote management is uncommon.
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