Electoral Snakes and Ladders
Anyone who has played snakes and ladders knows that, just before the winning square, there is always a big bad snake’s head, to take the would be winner right back to square one.
The ALP 1998 almost-victory is a classic tale of electoral snakes and ladders.
Labor candidates won 51.4 percent of the combined national vote, after preferences.
Using the cube rule, or the swing pendulum, which links the national vote with the number of seats won (after a uniform national swing), Labor candidates should have won about 80 seats, leaving John Howard with only 68.
Well comrades, we got the votes, and moved cheerfully up along the cube rule line, or the swing pendulum, right to the 80 seat mark, only to find the Coalition had got there before us, and moved the cube rule line vertically up by more than two percent. This big bad snake in the form of a new cube rule curve took Kim Beazley on a roller coaster back down to what looks like 66 seats.
According to the swing pendulum, the ALP needed a swing of about four percent of the vote, after preferences, to win a majority of the seats. Labor actually obtained a swing of 5.1 percent, after preferences, and yet still needs another 0.8 percent to win a majority of the seats. Anyone silly enough to still take notice of the pendulum device to predict the outcome in the House of Representatives should not be gainfully employed by any major party.
So, how does a party win a majority of preferred votes but not a majority of the seats?
The answer to the riddle is at once simple and complex.\
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