How this calculation works
Calculate the chance that a positive lognormal variable exceeds a threshold.
P(X>x) = normal upper tail of (ln(x)−μ)/σA worked example
With log mean 0 and log deviation ln(2), the threshold 4 is two log standard deviations above the mean.
Good to know
The parameters describe natural logarithms of observations.
Reference: OpenStax Introductory Statistics (opens in a new tab) ↗
Read the result
Calculate the chance that a positive lognormal variable exceeds a threshold.
The primary result is labeled “Probability above threshold”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
The parameters describe natural logarithms of observations.
For a related exercise, try the statistics calculator.
A few questions, answered
How can I check the default inputs by hand?
With log mean 0 and log deviation ln(2), the threshold 4 is two log standard deviations above the mean.
Which rule does this calculator apply?
P(X>x) = normal upper tail of (ln(x)−μ)/σ