In a weekend newspaper article, the well-known psephologist and election analyst, Malcolm Mackerras, argued that there have been only six federal election “landslide” victories.

In his article, Mackerras nominated the six elections as: 1917, 1929, 1931, 1943, 1966 and 1975.

Mackerras quite rightly objected to the idea that “every second federal election” is a landslide. He described the 2013 election as a “respectable loss” for the ALP but not worthy of being called a landslide.

He said: “However, I have a more rigorous definition, the details of which I have not the space to elaborate now.”

How To Define “Landslide”

I would suggest two essential election statistics as criteria for defining a landslide:

1. The proportion of House of Representatives seats held by the winning party or parties.
2. The national two-party-preferred vote achieved by the winning party or parties.

The primary vote achieved by the election winners is also of some interest but since our system of compulsory preferential voting always provides us with a national figure of combined primary and preferred votes the primary vote alone doesn’t necessarily mean much. [Read more…]