Triangular distribution

You can estimate a minimum, most-likely value, and maximum but have little raw data.

On this page
  1. Shape
  2. Use & avoid

Shape

Shape previewBounded by the minimum and maximum, with the highest likelihood at the mode.
Relative density
Duration (seconds)
min
2 s
mode
5 s
max
11 s

Use & avoid

Use when
You can estimate a minimum, most-likely value, and maximum but have little raw data.
Avoid when
You already have observations that should be represented empirically.
Support
Bounded between the stated minimum and maximum.
Parameters
Minimum, mode, and maximum.
Common mistake
Presenting an expert-estimated triangle as though it were a fitted distribution from measured data.
Example
Expert estimate: a task takes 2–11 minutes and is usually around 5.