Exponential distribution
Exponential distribution: use rate λ, elapsed quantity. Review the formula, worked example and calculation steps.
Inputs
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Formula & explanation
P(X≤x) = 1−exp(−λx)
Variables & units
- Rate λ
- Numeric value · minimum 0.000001, maximum 1000000000000
- Elapsed quantity
- Numeric value · minimum 0, maximum 1000000000000
Worked example
Rate0.5 and x2 gives 1−e⁻¹ ≈0.632121.
Assumptions
Nonnegative waiting-time model with constant hazard; rate units must match the inverse of x units.
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