Commentary: The Polls
Here’s a political quiz:
Which of the following is more annoying?
- Non-stop attack ads on your TV
- Public opinion pollsters calling your phone
- Both of the above are equally annoying
C is the correct answer, unless a pollster calls during dinner, in which case the correct answer is b. Or if it is a female calling, it would be a pollstress, I suppose.
Polling has been around forever and got scientific after the 1948 debacle when George Gallup decided Thomas Dewey was far enough ahead of Harry Truman that he quit polling three weeks before the election. Now it feels like polls are being conducted every three hours and we are deluged with results, some of them contradictory, especially polls for the presidential race. Why don’t polls agree and why do some polls simply get it wrong?
Part of the answer is straightforward. Pollsters use samples – you’d be surprised how small they are – just a few hundred people for a statewide or congressional race – so there is a built-in margin of error that the statisticians require. The margin is usually about four percent, so any poll result closer than that tells you that neither candidate has an advantage. Also, a poll can capture only the time period when it is conducted, so even tracking polls describe preferences for only three or four days.
The rest of the answer has to do with technology and the law. Pollsters who talk to you use random digit dialing but they have to call a lot of people to reach the people needed for the sample – say a single female who lives in a suburb. It takes as many as 25 calls before someone answers who will do the poll, which can take 20 minutes. It takes as many as 50 calls before someone who is in the 18-30 age group actually picks up the phone and does the poll. Further complicating this are cell phones. Almost one-third of all Americans have cells only -- they do not have a land line phone. And often they are not living in the area code where they bought the phone, further messing up the sample. And cell users have less patience for a poll and their surveys must be shorter, so less information is gathered. And if that weren’t enough, federal law prohibits computer-assisted calling to cells, so polling must be done by an actual person, doubling the cost of a poll. By now I bet you’re feeling sorry for the poor people who are employed to make calls for polling companies.
But as complicated, expensive and inexact as polling is, everyone does it and it will be a fixture of political campaigns for the indefinite future. So when tonight’s dinner is interrupted by a pollster calling, at least tell her to have a nice day.