Frequently Asked Questions
How can a sample population represent that of the whole population?
Public opinion polling anywhere in the world is based on the law of equal probability of selection which states that if every member of a population has an equal chance of being selected in a sample, that sample is representative of its population. It’s that simple.
Or for a more personal view; the next time you are in a hospital for a blood test
Ask the doctor to take all liters of blood in your body for the sample test.
What is a public opinion poll?
How are the surveys conducted?
Why should I participate in an opinion poll?
What is measurement error?
What is a Public Opinion Poll?
A poll is a type of survey or inquiry into public opinion conducted by interviewing a random sample of people
How are the surveys conducted?
Two of the most common ways that public opinion polls are completed is by telephone and face-to-face interviews. Other methods include mail, on-line and self-administered surveys
Why should I participate in an opinion poll?
Public policy decisions are being made all the time. There are all sorts of interest groups who are making their positions known to those decision-makers. The public opinion poll provides an opportunity for the voices of the common man and woman to be heard. So, why wouldn’t you want your views heard—it’s your privilege in a democratic society!
Measurement Error is error or bias that occurs when surveys do not survey what they intended to measure. This type of error results from flaws in the instrument, question wording, question order, interviewer error, timing, question response options, etc. This is perhaps the most common and most problematic collection of errors faced by the polling industry.