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Lies and statistics
Just when you thought the next federal election was a done deal
along come the opinion polls.
Last week an ACNielsen survey, published in Fairfax papers,
showed the coalition leading Labor 52 to 48 on a two-party preferred
That would be an even bigger win than the last election.
Two days later, Roy Morgan Research produced the same numbers but
transposed them to give a Labor victory.
And this week Newspoll in The Australian split the
difference to give us 50-50. Who can we believe?
We must, before answering that, address the Morgan Question.
Morgan once enjoyed possibly the best reputation of all our
Then came the 2001 election campaign, during which Morgan alone
predicted an ALP win by a big margin.
Managing Director Gary "We are the best in the
business" Morgan's characteristic assertiveness raised the
stakes further, and when election day went to the government, albeit
by a modest margin, Morgan's credibility suffered.
Morgan is also unique in sending interviewers into people's
homes; the others phone them.
On the one hand, face-to-face over a cuppa elicits more honest
On the other hand, phones have a wider reach, particularly among
rural voters, who tend to favour the conservatives.
Morgan says this can be corrected by weighting; the other outfits
point to the last election.
In any event, Morgan needs a good federal election to redeem
Sample size is another variant. Morgan's, at about 2000 a pop,
are twice the size of the other two. This should make them more
And preferences, with which two-party preferred numbers are
determined, are of increasing importance because minor party and
independent votes are growing.
Here it is Newspoll that is out of step, only measuring primary
votes and notionally distributing them as they flowed at the last
election. The other two outfits measure full preferences.
Other factors, such as sampling methodology and rotation of
questions, tend to remain close to pollsters' chests.
But the real answer to last fortnight's discrepancy is this:
there is none.
To give context, recall the NSW election in March.
Nielsen's final poll gave 58 to 42 in Labor's favour, Morgan's
was 60:40 and Newspoll's 60.5 to 39.5. ACNielsen proved to be the
most accurate, but all were in the right ballpark.
As all three are today, but the ballpark is around the half way
Notwithstanding Simon Crean's dreadful personal ratings and his
party's primary support, the main feature of published polls in this
current term is the closeness of the contest after preferences.
God didn't create opinion polling for us to take literally, just
to give us an indication.
A federal election today would probably be close, with the
Coalition favoured to win. That's what the published polls are
Peter Brent is editor of mumble.com.au, a website that looks
at electoral behaviour.
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