Density distributions of lognormal distributions (lines) get closer to normal density shaded area) as multiplicative standard deviation σ* decreases down to 1.2 for same μ* = 1.
Are already provided with the base stats package. See ?dlnorm
.
getLognormMode(mu = 0.6,sigma = 0.5)
## [1] 1.419068
getLognormMedian(mu = 0.6,sigma = 0.5)
## [1] 1.822119
(theta <- getLognormMoments(mu = 0.6,sigma = 0.5))
## mean var cv
## [1,] 2.064731 1.210833 0.5329404
Mode < Median < Mean for the right-skewed distribution.
The return type of getLognormMoments
is a matrix.
moments <- cbind(mean = c(1,1), var = c(0.2, 0.3)^2 )
(theta <- getParmsLognormForMoments( moments[,1], moments[,2]))
## mu sigma
## [1,] -0.01961036 0.1980422
## [2,] -0.04308885 0.2935604
The larger the spread, the more skewed is the distribution, here both with an expected value of one.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.