Math Playground
Data

Surveys

Design good questions, gather honest answers, analyse the results.

'Don't you agree the council is doing a terrible job?' versus 'How would you rate the council?' Same topic, wildly different answers. A survey question can lead a witness — and most do, by accident.

A survey gathers data by asking people questions. Its accuracy depends on three things: who you ask (sampling), what you ask (question design), and who actually answers (response rate).

Where you'll meet this

Politics, market research, public health, customer feedback, social science — surveys are how organisations 'hear' large populations. Badly designed ones produce confident nonsense.

researchpollingmedia literacy
Quick check

Which question is least likely to bias the answer?

Question-design traps

  • Leading questions — phrasing that suggests the answer ('Don't you agree…?').
  • Loaded words — emotionally charged terms ('death tax', 'pro-life').
  • Double-barrelled — two questions in one ('Is the food cheap and tasty?').
  • Vague scales — 'often / sometimes / rarely' mean different things to different people.
  • Order effects — earlier questions colour later answers.
Your turn

What's wrong with: 'How satisfied are you with our fast, friendly service?'

Try it

Why do response rates matter as much as sample size?

If 90% of those contacted refuse, the 10% who answered are unusual — more motivated, more opinionated, often angrier. Non-response bias can wreck a survey with a huge nominal sample. A small survey with a high response rate often beats a big one with a low one.

Watch out

Treating a self-selected online poll as a real survey. 'Vote in our poll!' attracts the motivated and the organised, not a random cross-section. It measures who clicked, not what the public thinks.

Before believing a survey result, ask: *who was sampled, how were the questions worded, and what was the response rate?* If the article won't tell you, be sceptical.

Recap
  • Survey quality = sampling + question wording + response rate.
  • Avoid leading, loaded, double-barrelled, and vague questions.
  • Self-selected online polls aren't surveys — they measure who bothered to click.