 |
research
services research
productsopinion
polling about
us location testimonials
RED
C & Polling The Methodology
RED C use a telephone approach for political polling, as it has been found worldwide to gain a more representative sample than a face to face approach when conducting political opinion polls.
To
ensure our sample is totally representative we use an approach called
random digit dialling to create a database of telephone numbers. This
method is commonly used in market research, and involves first selecting
a random sample from directories of all numbers across Ireland and
then adding +1 or + 3 to this number. By doing this we are able to ensure
we reach all telephone households, including those that are ex-directory.
RED C are also one of the first research companies in the world to change their sampling approach in order to take account of the growing number of voters who only have a mobile phone. This was incorporated prior to the general election in 2007. Half of our sample is now conducted through calls to mobile numbers, again using an RDD approach. This ensures that our sample reaches 98% of all adults in the population, including those people who only have a mobile, those who only have a landline and those who have both.
Quotas are then set on demographics such as age, sex, social class and region to ensure that the people we speak to are representative of all adults aged 18+, based on the very latest Census statistics. The final data is then also weighted to these demographic parameters as a final check to ensure the sample is entirely representative.
For all national population opinion polls RED C interview a random sample of 1,000+ adults aged 18+ by telephone. This sample size is the recognised sample required by polling organisations for ensuring accuracy on political voting intention surveys. The accuracy level is estimated to be approximately plus or minus 3 per cent on any given result at 95% confidence levels.
For constituency surveys we will conduct among a smaller sample size of 500 adults 18+, either by telephone if transfer analysis is not required or face to face if it is required.
In all respects the survey's we conduct are within the ESOMAR (European Society for Opinion and Marketing Research) guidelines for political and opinion polling.
 |
