(logarithmic normal distribution) A statistical probability-density function, characterized by two parameters, that can sometimes provide a faithful representation of a polymer’s molecular-weight distribution or the distribution of particle sizes in ground, brittle materials. It is a variant of the familiar normal or Gaussian distribution in which the logarithm of the measured quantity replaces the quantity itself. It’s mathematical for is
or
α and β are the mean and standard deviation of ln x. Anti-ln α is called the log mean of x. To test the suitability of this distribution, one plots the cumulative percent of members having weights or sizes below x, versus x, on lognormal probability paper and looks for linearity in the plot.
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Gooch, J.W. (2011). Log normal Distribution. In: Gooch, J.W. (eds) Encyclopedic Dictionary of Polymers. Springer, New York, NY. https://doi.org/10.1007/978-1-4419-6247-8_7002
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