The recipe for a strong and precise survey

Throughout the election season, news agencies and campaigns will portray the polls as a snapshot of a political race. In the end, the only poll that matters are the votes cast on election day.

But what makes a sound and accurate survey? Guy Golan, associate professor of strategic communication at Bob Schieffer College of Communication at Texas Christian University, said capital tonight that a good sample leads to a more accurate result.

Even with a large amount of resources, a polling station cannot reach every voter in an electoral district to really see what every voter thinks of a race. These pollsters take a small sample of a district and extrapolate their results to provide insight into how voters are feeling at a specific time. Golan uses the analogy of a bowl of soup: a large spoonful can get more of a soup’s different ingredients. This means that a larger sample can get a clearer picture of a district’s mood.

Pollsters also use a process of weighting their responses to get a more accurate picture of a district. If a district has a large number of college graduates but a small number of such graduates in their sample, they will weight the college graduate response more to approximate the composition of the district they are surveying.

Polls have gotten a bad rap since the 2016 election for not accurately projecting former President Donald Trump’s victory over former Secretary of State Hillary Clinton. Golan said polls sometimes run into problems, with respondents not being representative of the district, fewer people answering or completing a poll, and distrust of pollsters, especially on the right of the political spectrum. Distrust could lead to undersampling of conservative voters.

Golan said the polls could be used to help sway undecided voters in a close election and potentially swing the election in their favor. Golan argues that undecided voters generally want to support a winning candidate. If a candidate is leading in the polls in a close election, an undecided voter may support them and push that candidate across the finish line.