How did the pollsters go?
So how did the pollsters go? I will do an updated post once we have final results, but here is the situation for now:
Actual | TVNZ | TV3 | Herald | Fairfax | Morgan | |
National | 45.5% | 47.0% | 46.0% | 47.9% | 49.0% | 42.0% |
Labour | 33.8% | 35.0% | 33.1% | 36.4% | 31.0% | 34.5% |
Green | 6.4% | 9.0% | 9.0% | 5.8% | 8.0% | 10.0% |
NZ First | 4.2% | 2.4% | 3.4% | 3.9% | 3.0% | 4.5% |
Maori | 2.2% | 1.3% | 2.7% | 2.3% | 3.0% | 2.5% |
United Future | 0.9% | 0.0% | 0.2% | 0.7% | 1.0% | 1.0% |
ACT | 3.7% | 2.5% | 2.8% | 1.8% | 4.0% | 4.0% |
Progressive | 0.9% | 0.0% | 0.3% | 0.2% | 0.0% | 0.0% |
There are numerous ways one can judge accuracy. We’ll look at results for each party, the results for the National-Labour margin and then finally the average they were out overall.
National – TV3 were closest – just 0.5% out
Labour – TV3 and Morgan were both closest – each out by 0.7% but on different sides
Green – Herald were closest – 0.6% below. The cloest above was Fairfax at 1.6% too high.
NZ First – Morgan and Herald both 0.3% out – one above and one below.
Maori – Herald near dead on at 0.1% too high
United Future – Fairfax and Morgan both just 0.1% too high
ACT – Fairfax and Morgan both 0.3% out only
Progressive – No one had them close – TV3 closest at 0.3%. This is because people vote for Anderton’s name on the ballot, not Progressive, I suspect.
National-Labour gap. It is (for now) 11.7%. TVNZ had it at 12%, TV at 12.9%, Herald at 11.5%, Fairfax at 18% and Morgan at 7.5%. The last two were pretty far out. The other three can all be pretty pleased. I won’t call a winner until final result.
Average difference – If you average the difference for all eight parties, then the average “out” was 1.4% for TVNZ and Fairfax, 1.2% Morgan, 1.1% Herald and 0.9% TV3. But this is a bit misleading as it treats being 1% out for 50% the same as being 1% out for 5%. For the final results, I may look at whether they were within the margin of errors.
In the end four of the five polling companies correctly picked a centre-right Government without needing the Maori Party. Roy Morgan was the only dissenter, but to be fair to them their poll was done over two weeks, while the others were done over a few days from the end of the second week to middle of the last week.