Idea 11of 22Builds onA sample with the school's mix
Names in a hat
How do you give every person the same chance?
Today you'll discover
- what simple random sampling is
- ways to draw at random
- what “random” does not mean
Think firstAll 60 names go in one hat
Sam puts all 60 names in a hat and pulls 10. Who could be picked?
Decide first, then press Next. Watch where the ringed students are in the grid.
The same 60 students. A dashed outline goes round all of them and a hat holds every name. Then 10 marks, scattered across the whole grid, are ringed. At the right: 3 of 10 want a court; all 60 students, 18 of 60.
See the whole ideathe big idea and the key word, in one place
The big idea
In simple random sampling, every person has the same chance of being picked.
For exampleNames in a hat, numbered slips in a box, or a random number generator on a computer: each one is simple random sampling.
Easy to get wrong“Random” does not mean “whoever I bump into”. Bumping into people favours whoever happens to be nearby.
Key word
- simple random sampling
- choosing a sample so that every member of the population has the same chance of being picked
Ready to use it?
- Name simple random sampling from a description.
- Plan a simple random sample.