By Nick O’Hara
It is an often-lamented fact that there seems to be very little difference between the major political parties. We only need to look at our existing PM Malcolm Turnbull’s centrist views and the Oppositions mild objections to begin to question where the real differences are. Moreover, it often seems like politicians are simply unwilling to announce policies of any type, certainly substantive ones, purely because it would open them up to attack.
The Median Voter Theorem, which has its origins in Harold Hotelling’s 1929 work, offers an interesting explanation for this. The theory states (with a few simplifying assumptions) that a majority rule voting system will choose the outcome most preferred by the median voter. The idea is that if political views can be represented on a simple political spectrum from Left to Right (see above) politicians will effectively compete to win the centre vote. The intuition is that appealing to the centre may lose you some of your more radical supporters, but it should give you a larger population of moderate supporters. For a more detailed proof of the theory, and discussion of its limitations, check out This Article.
The Median Voter Theorem can be extremely useful in helping explain the actions of political parties and their leaders. For example, it suggests that:
• Political parties may adopt similar policies to each other in order to try and appeal to more moderate, central voters (sometimes even if this goes against the party’s traditional values).
• Politicians may give evasive answers to questions purely to avoid having to take a stance on an issue that may lose them moderate votes.
• Politicians seem to use more moderate rhetoric as they get closer to an election in order to try and win centrist voters (under the belief that they have already secured the votes of their core party supporters).
Needless to say the concept is based on numerous assumptions, such as single-peaked preferences and a tidy one-dimensional political spectrum. Furthermore, there are plenty of exceptions to the rule – just think about the popularity of Trump/Sanders in the US. However, in the modern political arena dominated by vague answers and uninspiring policies, it certainly seems like there’s some relevance to the theory.