Methodology:
 
Elections in Saskatchewan employ a "first-past-the-post" voting system. Thus the prediction of the election result in terms of the seats distribution in the provincial legislature is based on a prediction of the election result in each constituency. The use of a voter migration matrix reflects the notion that voters change their opinion about candidates and parties in a similar way across the entire province. That is, a party that gains or loses vote in one constituency tends to gain or lose votes in other constituencies. In the simplest form, this "swing" can be applied across all constituencies.
 
Naturally, applying this simple voter migration matrix to the election results from a previous election is a simplistic way of forecasting the outcome of a forthcoming election. It is simplistic in three ways. First, it does not reflect the change in population. Some children have reached voting age, some (mostly older) people have died, and other people have moved to Saskatchewan or have moved away from Saskatchewan. Second, it does not reflect the possibility that voters from the last election abstain in the forthcoming election, or abstainers in the last election choose to vote in the forthcoming election. Third, the voter migration matrix is applied identically across all constituencies, thus ignoring important local factors. A more sophisticated approach would take care of these three problems.