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I am interested to know how one can derive, from first principles, the Weibull distribution. As I understand it, the Weibull distribution $$D_{w}(x) = \frac{k}{\lambda} \left(\frac{x}{\lambda}\right)^{k-1} e^{{(-x/\lambda)}^{k}}$$ is a generalised form of the Rayleigh distribution $$ D_{R}(x) = \frac{x}{\sigma^{2}} e^{-x^{2}/(2\sigma^{2})} $$ when $k = 2$ and $\lambda = \sqrt{2}\sigma$.

The Rayleigh distribution can be derived from first principles very easily. Consider a vector, $\mathbf{v} = (x, y)$ where $x$ and $y$ are Gaussian distributed. If the overall magnitude of $\mathbf{v}$ is considered a Rayleigh distribution emerges.

Is there a similar argument one can make to derive the Weibull distribution? OIf not, how can one derive the Weibull from first principles?


Motivation: I know one can just introduce a shape parameter. I am trying to et an understanding of how Weibull's emerge in nature with some physical intuition. Very much in the same way as one can think how the Rayleigh emerges.

user27119
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Brown and Wohletz [1] derive the Weibull distribution from a sequential fragmentation process. In the limit, the distribution of particle number is Weibull distributed. This discussion is completed on the first page of the cited paper. The paper also provides other connections with other processes and distributions which might provide additional intuition.

[1] Brown, Wilbur and Kenneth H. Wohletz, "Derivation of the Weibull distribution based on physical principles and its connection to the Rosin-Rammler and lognormal distributions", Journal of Applied Physics, vol. 78, no. 4, 15 August 1995, pp. 2758-63. https://www.lanl.gov/orgs/ees/geodynamics/Wohletz/SFT_Weibull.pdf

Eric Towers
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