Why do polls always seem to get it wrong? From Brexit to the US election

AT THE start of election day virtually every poll, political analyst, expert and insider had Hillary Clinton packing her bags for the White House.

By the time polls had closed on Tuesday night, those projections had been left in tatters — just like the ones that duped David Cameron ahead of the Brexit vote this summer.

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The billionaire notched upset victories in Florida, North Carolina and Wisconsin — critical swing states where almost every public poll and most private projections had shown Clinton ahead.

The Republican nominee’s surprisingly strong performance go some way to validate his claims that many polls "just put out phony numbers"

So why were the polls so wrong?

Veteran Democratic pollster Geoff Garin belives many surveys had under-sampled non-college-educated whites, a group that Trump appealed to.

He also argued there had been on over-emphasis on the belief that the country’s rising demographic diversity would put Clinton over the top.

“There was too great a belief that demographics are destiny, and that demographics would lead to a certain outcome,” he said.

“The reality turned out to be much different that."

Others pointed to the possibility of the 'hidden Trump voters' - - those who were too embarrassed to admit even anonymously to pollsters that they planned to support the republican.

Then there was the surge in momentum Trump received when the FBI announced 11 days before the election that it was reviewing new evidence related to its investigation into the handling of sensitive information by Clinton and her aides at the State Department.

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That sounds familiar, did that happen with Brexit?

Yes. Just like last year's General Election, the polls led us up the garden path.

On the day, YouGov predicted the Remain campaign would win, and the final three polls before the referendum all said the same thing: the UK would vote – albeit by a small margin – to stay in the EU.

With hours to of, the bookies were 9 to 1 on that the UK would stay in the EU.

But, yet again, the politicians and pollsters were proved wrong.

In some areas, turnout was lower than expected.

But the final numbers speak for themselves: a large group of people who'd been assumed to vote Remain did the opposite.

These voters are not the ones who wore ‘I’m OUT’ stickers they were the 'secret leave' voters.

Were any of the US polls right?

Yes some were. Over the last two months, 10 polls published on  gave Trump the lead.

Nine of these were from from LA Times/ USC, and one was from Fox - out of a total of 93 polls between 8 September and 8 November.

The LA Times was the only polling company to consistently pick out Trump's lead.

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