Software developers have long tried to develop tools to guide indecisive voters towards picking a candidate. Most of the ones I've seen appear to operate according to civics-class logic, in which the party or candidate who agrees with you most closely on the greatest number of issues deserves your vote.
The CBC's new Vote Compass web app, launched in advance of next week's provincial elections in Québec, probably comes close than any other I've seen to accounting for all the other ways voters find themselves cross-pressured as election day approaches. Perhaps most impressively it does so in a multi-party system where, as one Canadian campaign hand wrote me, "you may know which parties you oppose, but not whom to support."
Vote Compass begins with by asking a user to declare her views on a standard run of policy concerns, such as "the crucifix should continue to be displayed in the National Assembly," "only the Anglophone community should have access to Anglophone CEGEPs," and "the Caisse de dépôt et placement should put Quebec's economic interests ahead of its own financial gain." Then voters order the relative importance of each category (economic, environmental, etc.) of issues to their worldview.
But then the app also takes stock of non-issue consderations, such as the perceived trustworthiness and competence of party leaders, one's estimation of how corrupt each party is, and the potential for strategic voting—by asking a user to state how likely she thinks each party is to win in her constituency.
The app also asks a number of optional demographic questions, suggesting that its academic patrons at Université Laval are likely collecting an interesting data set about voter behavior in multi-party environments. Check out the app here; it's worth playing around with, even at the expense of polluting the data by creating an unlikely bloc of fictive Catholic, Anglophone redistributionists with strong views about how Québecois agricultural land should be made available to foreigners.