Statements (40)
Predicate | Object |
---|---|
gptkbp:instanceOf |
Probability distribution
|
gptkbp:affiliatedWith |
continuous probability distributions
|
gptkbp:alsoKnownAs |
gptkb:lognormal_distribution
|
gptkbp:application |
modeling income distribution
modeling stock prices modeling particle sizes modeling biological measurements |
gptkbp:category |
distributions with positive support
right-skewed distributions |
gptkbp:characteristic |
does not have a simple closed form
|
gptkbp:compatibleWith |
symmetric
|
gptkbp:cumulativeDistributionFunction |
F(x; μ, σ) = 0.5 + 0.5 erf[(ln x - μ)/(σ√2)]
|
gptkbp:definedIn |
a probability distribution of a random variable whose logarithm is normally distributed
|
gptkbp:describedYear |
1879
|
gptkbp:entropy |
μ + 0.5 + ln(σ√(2π))
|
gptkbp:firstDescribed |
gptkb:Francis_Galton
|
gptkbp:heldBy |
positively skewed
|
https://www.w3.org/2000/01/rdf-schema#label |
Log-normal distribution
|
gptkbp:kurtosis |
exp(4σ^2) + 2exp(3σ^2) + 3exp(2σ^2) - 6
|
gptkbp:meaning |
exp(μ + σ^2/2)
|
gptkbp:medium |
exp(μ)
|
gptkbp:mode |
exp(μ - σ^2)
|
gptkbp:momentGeneratingFunction |
does not exist for all t
|
gptkbp:originatedIn |
multiplicative processes
|
gptkbp:parameter |
μ (mean of log), σ (standard deviation of log)
|
gptkbp:probabilityDensityFunction |
f(x; μ, σ) = (1/(xσ√(2π))) exp(-(ln x - μ)^2/(2σ^2)), x > 0
|
gptkbp:relatedTo |
gptkb:Weibull_distribution
gptkb:Exponential_distribution gptkb:Gamma_distribution gptkb:Normal_distribution |
gptkbp:skewness |
(exp(σ^2) + 2)√(exp(σ^2) - 1)
|
gptkbp:supports |
x > 0
|
gptkbp:usedIn |
biology
environmental science finance hydrology reliability engineering |
gptkbp:variant |
[exp(σ^2) - 1] exp(2μ + σ^2)
|
gptkbp:bfsParent |
gptkb:Log-gamma_distribution
|
gptkbp:bfsLayer |
7
|