The Science ofOpinion Polling

October 2010

Agenda

 

1. Some questions answered about polling

2. The RED C Approach to getting polls right

3. Why do different polls give different results?

4. Current party support

5. What the future holds

Reputable polling firm?

Reputation is important to a quality firm

Association membership

…..check who paid for the poll!

Who did the poll?

Why you should use a reputable opinionpoll company!

How many people here today have been surveyed

for an opinion poll?

How come I am never called for a poll?

Over 4 Million people!

Only about 15 national polls are published each year

Approx. 60,000 people contacted and 15,000 people interviewed

Less than 1% of the population.

How can 1000 people represent the whole population?

“If you don't believe in random

sampling….

…next time you go for a blood test ask them to take it all!”

What is the possible error of opinion polls?

AIMRO guidelines = minimum sample of 1000 interviews for a national poll.

Sample error of just + or -3%

Local or regional polls = 500 interviews.

This does increase the possible error to + or – 4.5%

Does it matter when a poll was done? Even bad publicity can give parties a boost!

Events can have a dramatic impact on poll results.

Do people not just lie to pollsters?

1. Why bother? Easier to tell the truth

2. If people did often lie, opinion polls would never get their predictions correct.

3. Code of conduct by proper industry players means results are collected on an unattributable basis, so there should be no reason to lie.

How were the interviews conducted?

The key here is that the poll is conducted outbound by the company – not a phone-in poll.

These types of polls are normally conducted face to face or by phone.

Online polls should still be treated with caution in Ireland – over 55’s not represented.

Problems for Face to Face Interviewers

Apartments Country Houses

RED C Method for Getting Polls Right

RED C conducts polls by phone, because we believe they are more accurate.

Telephone interviewer has no control over who they interview.

This makes respondent selection truly random as the interviewer doesn’t know if the person is in an apartment or country house!

Provides a base sample that is more representative.

How do we make sure the sample is accurate?

1. Random Digit Dialling Initial random sample of directories nationwide – then +1 or +3 added to number – ensures ex-directory households included

2. Mobile sample25% of the Irish Population now mobile onlyHalf sample with landlines and half with mobiles – reach is 98% of the population

3. QuotasQuotas set based on census data for gender, age, region and social class to ensure the sample is representative.

How important are the questions that are asked?

Question wording and order of questions are vital

RED C always ask voting intention first, as other questions such as party leader ratings may bias results.

On the phone it is also important to prompt for ALL parties.

RED C techniques employed to maximise accuracy

Likelihood to Vote

Not everyone votes – turnout 67% at the last election….

…this needs to be taken account of in the analysis

Only look at results by those likely to vote (on a ten point scale exclude those who say they are 1-3)

Turnout GE 2007

67%

RED C techniques employed to maximise accuracy

Weighting by past vote

Demographics do not necessarily give us a 100% accurate sample

Sometimes recall of how people voted last time is different to the result.

Part faulty recall ….BUT part suggesting a biased sample

RED C compares the declared past votes to the actual result of the last general election and weights to the mid-point of the two.

The benefits of Regular Tracking

Statistical theories prove that, in a random poll of 1,000, 19 times out of 20 a poll will be accurate to within 3 per cent.

But this does leave the one in 20 chance of the result being outside this margin of error – a Rogue Poll

It is sensible to weigh up the results of several different polls when calculating the most likely outcome.

33 33

67 67

How accurate are opinion polls then?

RED C had four of the five most accurate pre-election polls in 2007. 

Final GE 2007 poll had an average sample error of just 1.4%.

2009 local elections saw an average error of just 2.1% - as accurate as the exit poll.

The Lisbon Treaty result was predicted with 100% accuracy.

Yes – in favour

No - against

Last RED C

Poll%

Final Result

%

Lisbon Treaty Sep 2009

Why are do polls from different companies show different results?

Volatile nature of electorate

Events that happen during or before polls.

Different method – phone vs. face to face

Different question wording & order.

Analysis techniques – likely voters & past vote weighting

A Rogue Poll!

Normally they don’t!1.Last general election all were within average 1-2% error of the final result

2.Biggest gap for any party across all the pollsters was just 2%

BUT POSSIBLY…..

Fianna Fáil

Fine Gael

Labour

Sinn Féin

Green Party

PDs

Independent

Current trends in 1st preference vote intention(Base: All adults likely to vote 18+)

31%

24%23%

10%

3%

9%

Banking CrisisStarts

Cowen FF Leader

TD’s Pay Increase

+ Tribunal

EconomyWorsens

Lisbon Treaty 2

Budget 2009

FGHeave

Local Elections

What can we expect in the run up to the election?

1. The electorate are volatile – 50% of those still undecided voted Fianna Fail at the last election

2. The ability to handle the economy is the most important aspect for voters in the run up to next election, BUT…… no major party currently has that support – only 30% of the electorate believe Fine Gael/Labour coalition can handle the economy despite joint 1st preference of 56%!

3. Current support for Fine Gael and Labour may not be built on very strong foundations – however the desire to punish Fianna Fail remains.

4. 1 in 5 voters only made up their mind in the last week of the election campaign in 2007.

…plenty of room for more changes before an election is held