According to the most recent democratic primary poll from NBC and the Wall Street Journal, Joe Biden is favored to win the democratic nomination over Bernie Sanders. According to the most recent democratic primary poll from Politico, Joe Biden is favored by 56 percent of those surveyed, with Sanders following at 38 percent. And according to various polling sources, there’s a startlingly high chance you were not included in either of these polls. There’s an even higher chance that you have not been included in any political polls used to predict the results of the various elections throughout time.
One of the top polling entities in the nation, Gallup, only talks with 1,000 people each time they conduct a survey. This means they are relying on 1,000 people to predict the views of millions of Americans. Unsurprisingly, they get a flood of emails and calls each time a poll is released, from unselected citizens curious as to how to take political polls.
It’s actually highly unlikely that you will ever personally be selected to take part in a national poll. You will probably also never know anyone who has taken part in one of these polls. In fact, George Gallup himself once told a woman that it was probably more likely for her to be struck by lightning that be selected for one of his polls. So how does it work?
It would be impossible for a polling entity to personally speak to every single U.S. citizen each time they conduct a survey. Therefore, they’ve concocted a workaround, called a probability sample. Theoretically, this sample would be able to represent the attitudes, behaviors and options of an entire population. If done correctly, the sample results would be identical to the results of a full population survey. To achieve this, the sample pulls from equal demographics such as race, gender, age and education level. If any demographic is represented more than the others, the poll will automatically be skewed.
When you look at a national poll, you’ve probably seen the predicted “margin of sampling error.” This number gives the polling places a safety net against any uncertainty. For example, a margin of plus or minus two points shows that the candidates’ support could be two points either higher or lower than the poll reports. This allows the poll conductors to report totals with 95 percent accuracy, while protecting themselves from complications such as people not answering their phones.
While there’s a high likelihood you’ll never be selected to take part in a national poll, this doesn’t mean their results are invalid. Since poll conductors work hard to create an accurate slice of the population for each poll, you can read the results with certainty and confidence.