Random sample selector
Pick a simple random sample of record numbers from a numbered list, such as patient files, with a seed so the draw can be repeated.
Your data does not go to our server. This tool runs in your browser; what you type or open never leaves your device.
This calculator needs JavaScript, because it calculates in your browser and sends nothing. Turn JavaScript on to use it. How it is calculated is explained below.
- Seed (use it to repeat this draw)
- Selected numbers
How it is calculated
Every record has the same chance of being chosen and no number appears twice. The numbers are shown in ascending order.
The draw is made in your browser; the list of numbers is never sent to us.
Floyd's algorithm: n distinct numbers from 1…N, every possible sample equally likely
Worked example: N = 100, sample size 10, seed 5: the same ten numbers every time you use seed 5.
Sources
These calculators support research; they do not replace the advice of a statistician or a clinician.
Questions
How do I use the numbers?
Number your list from 1 to N in a fixed order (for example by admission date), then take the records whose numbers are shown. Keep the seed and the order so that the draw can be repeated.