How this calculation works
Evaluate the cumulative probability and mean of a beta distribution on [0,1].
THE FORMULA
F(x)=Iₓ(α,β), the regularized incomplete beta functionA worked example
A Beta(2,2) density is symmetric, so its cumulative probability at 0.5 is 0.5.
Good to know
Shape parameters must be positive.
Reference: OpenStax Introductory Statistics (opens in a new tab) ↗
Read the result
Evaluate the cumulative probability and mean of a beta distribution on [0,1].
The primary result is labeled “Probability at or below threshold”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
Shape parameters must be positive.
For a related exercise, try the statistics calculator.
A few questions, answered
How can I check the default inputs by hand?
A Beta(2,2) density is symmetric, so its cumulative probability at 0.5 is 0.5.
Which rule does this calculator apply?
F(x)=Iₓ(α,β), the regularized incomplete beta function