Data Collection, Sampling and Surveys

What the resources cover

Most of this unit is about sampling. You will find mind maps such as Sampling Methods and Sampling Techniques, which split the topic into probability and non-probability sampling. Probability methods include simple random, systematic, stratified and cluster sampling. Non-probability methods include snowball and convenience sampling.

Other resources look at what can go wrong. There are maps on Bias and Voluntary Response Bias, plus a slide set on non-sampling errors in polls and surveys. For survey design, see the maps Types of Survey Questions and Survey lifecyle from a design perspective.

Where to start

Begin with the flashcard deck 1. Statistical Sampling. It asks you to define population and sample, and to weigh the advantages and disadvantages of a census against a sample. Once those terms feel familiar, open the mind map Sampling Methods to see the main types side by side.

1. Learn the key words with a flashcard deck.
2. Compare the methods on a mind map.
3. Check your understanding with a quiz.
4. Look at bias and survey questions last.

Using quizzes and maps together

The quiz Sampling Techniques In Data Science starts from the basics: what a population is and what its size means. Applied Statistical Methods 1 uses a real-style scenario about the purchasing habits of local residents. Another quiz, Random Sampling Practice, gives you more questions on the same ideas.

Take a quiz first, note the questions you missed, then go back to the matching map. Redo the quiz afterwards and see what has changed.

Where this unit fits

This unit sits in the Statistical Investigation and Data Collection strand of Statistics and probability. The resources mention AP Statistics, GCSE Statistics and A-level Maths, and many are written at university level too. They were made by GoConqr users, so styles and depth vary.

Choose one resource that matches what you are studying now, and work through it at your own pace.