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**Hugh** · 31-03-2019, 09:56

Quote:

Originally Posted by pip08456

How anyone can believe a poll of (on average) 2000 people reflects the entire nation is beyond me.

As Mick says, the only poll that matters is the one with the cross in the box.

Hope this clarifies thing - statistical methodology explained.

http://www.britishpollingcouncil.org...opinion-polls/

Quote:

3. How does a poll choose a sample that is truly representative?
There two main methods. The first is “random” sampling, the second “quota sampling”. With random sampling, a polling company either uses a list of randomly-drawn telephone numbers or email addresses (for telephone or some Internet polls); or visits randomly-drawn addresses or names from a list such as an electoral register (for some face-to-face surveys). The polling company then contacts people on those telephone numbers or at those addresses, and asks them to take part in the survey.

“Quota” sampling involves setting quotas — for example, age and gender — and seeking out different people in each location who, together, match those characteristics. Quota polls are often used in face-to-face surveys. In addition, some Internet polls employ quota samples to select representative samples from a database of people who have already provided such information about themselves...

...7. How can you possibly tell what millions of people think by asking just 1,000 or 2,000 respondents?
In much the same way that a chef can judge a large vat of soup by tasting just one spoonful. Providing that the soup has been well stirred, so that the spoonful is properly “representative”, one spoonful is sufficient. Polls operate on the same principle: achieving representative samples is broadly akin to stirring the soup. A non-scientific survey is like an unstirred vat of soup. A chef could drink a large amount from the top of the vat, and still obtain a misleading view if some of the ingredients have sunk to the bottom. Just as the trick in checking soup is to stir well, rather than to drink lots, so the essence of a scientific poll is to secure a representative sample, rather than a vast one

8. But isn’t there some risk of sampling error in a poll of 1,000 or 2,000 people?
Yes. Statistical theory allows us to estimate this. Imagine a country that divides exactly equally on some issue — 50% hold one view while the other 50% think the opposite. Statistical theory tells us that, in a random poll of 1,000 people, with a 100% response rate, then 19 times out of 20, a poll will be accurate to within 3%. In other words, it will record at least 47%, and no more than 53%, for each view. But there is a one in 20 chance that the poll will fall outside this range.

With a sample of 2,000, the poll will be within 2% 19 times out of 20.

---------- Post added at 09:56 ---------- Previous post was at 09:55 ----------

Quote:

Originally Posted by RichardCoulter

As per the Radio 4 news yesterday, if Parliament takes over and passes legislation, the Government has a right to ask the Queen to refuse to give the bill royal assent.

This has not been done since 1707.

It was also in the Times today -can’t see her agreeing to do that.