A person’s age is one of the most valuable and informative demographic characteristics available to those who study public opinion. The age of a person is a number of things: it places them in the biological cycle from birth to the end of life; it corresponds roughly with their social role and responsibility in the world; and, it positions us all as members of a similar group who share the same experiences as the years pass. These three ways of looking at age can be useful for those who are interested in social behavior.
Age is easier to measure than religious affiliation, race, or gender. Some organizations ask for the respondent’s current age, while others ask for year of birth.
We use both methods, depending on what the survey is about. Since we keep panelists on the American Trends Panel for many years, their birth year is not likely to change. Still, relying only on age or year of birth collected once a year means that a panelist’s age is updated at an arbitrary point in the year (at the time of our annual data collection) rather than on their actual birthday and so their age is…
