Kaniadakis Weibull distribution

{{Short description|Continuous probability distribution}}{{Notability|date=February 2023}}{{Infobox probability distribution

| name = κ-Weibull distribution

| type = density

| parameters = 0 < \kappa < 1
\alpha > 0 rate shape (real)
\beta> 0 rate (real)

| support = x \in [0, +\infty)

| pdf = \frac{ \alpha \beta x^{ \alpha - 1 } } { \sqrt{ 1 + \kappa^2 \beta^2 x^{2 \alpha} } } \exp_\kappa ( - \beta x^\alpha )

| cdf = 1 - \exp_\kappa(-\beta x^\alpha)

|pdf_image=File:Kaniadakis weibull pdf.png|cdf_image=File:Kaniadakis weibull cdf.png|moments= \frac{ (2 \kappa \beta )^{-m/ \alpha } }{ 1 + \kappa \frac{ m }{ \alpha } } \frac{ \Gamma \Big( \frac{ 1 }{ 2 \kappa }-\frac{m}{2 \alpha }\Big)}{ \Gamma \Big(\frac{1}{2 \kappa }+\frac{m}{2 \alpha } \Big) } \Gamma \Big(1+\frac{m}{ \alpha } \Big) |mode= \beta^{ -1 / \alpha } \Bigg( \frac{ \alpha^2 + 2 \kappa^2 (\alpha - 1 )}{ 2 \kappa^2 ( \alpha^2 - \kappa^2)} \sqrt{1 + \frac{4 \kappa^2 (\alpha^2 - \kappa^2 )( \alpha - 1)^2}{ [ \alpha^2 + 2 \kappa^2 (\alpha - 1) ]^2} } - 1 \Bigg)^{1/2 \alpha} |median= \beta^{-1/\alpha} \Bigg(\ln_\kappa (2)\Bigg)^{1/\alpha} |quantile= \beta^{-1 / \alpha } \Bigg[ \ln_\kappa \Bigg(\frac{1}{1 - F_\kappa} \Bigg) \Bigg]^{1/ \alpha} }}

The Kaniadakis Weibull distribution (or κ-Weibull distribution) is a probability distribution arising as a generalization of the Weibull distribution.{{Cite journal |last1=Clementi |first1=F. |last2=Gallegati |first2=M. |last3=Kaniadakis |first3=G. |date=2007 |title=κ-generalized statistics in personal income distribution |url=http://link.springer.com/10.1140/epjb/e2007-00120-9 |journal=The European Physical Journal B |language=en |volume=57 |issue=2 |pages=187–193 |doi=10.1140/epjb/e2007-00120-9 |arxiv=physics/0607293 |bibcode=2007EPJB...57..187C |s2cid=15777288 |issn=1434-6028}}{{Cite journal |last1=Clementi |first1=F. |last2=Di Matteo |first2=T.|author2-link=Tiziana Di Matteo (econophysicist) |last3=Gallegati |first3=M. |last4=Kaniadakis |first4=G. |date=2008 |title=The -generalized distribution: A new descriptive model for the size distribution of incomes |url=https://linkinghub.elsevier.com/retrieve/pii/S0378437108001349 |journal=Physica A: Statistical Mechanics and Its Applications |language=en |volume=387 |issue=13 |pages=3201–3208 |doi=10.1016/j.physa.2008.01.109|arxiv=0710.3645 |s2cid=2590064 }} It is one example of a Kaniadakis κ-distribution. The κ-Weibull distribution has been adopted successfully for describing a wide variety of complex systems in seismology, economy, epidemiology, among many others.

Definitions

= Probability density function =

The Kaniadakis κ-Weibull distribution is exhibits power-law right tails, and it has the following probability density function:{{Cite journal |last=Kaniadakis |first=G. |date=2021-01-01 |title=New power-law tailed distributions emerging in κ-statistics (a) |url=https://iopscience.iop.org/article/10.1209/0295-5075/133/10002 |journal=Europhysics Letters |volume=133 |issue=1 |pages=10002 |doi=10.1209/0295-5075/133/10002 |arxiv=2203.01743 |bibcode=2021EL....13310002K |s2cid=234144356 |issn=0295-5075}}

:

f_{_{\kappa}}(x) =

\frac{\alpha \beta x^{\alpha-1}}{\sqrt{1+\kappa^2 \beta^2 x^{2\alpha} }} \exp_\kappa(-\beta x^\alpha)

valid for x \geq 0, where |\kappa| < 1 is the entropic index associated with the Kaniadakis entropy, \beta > 0 is the scale parameter, and \alpha > 0 is the shape parameter or Weibull modulus.

The Weibull distribution is recovered as \kappa \rightarrow 0.

= Cumulative distribution function =

The cumulative distribution function of κ-Weibull distribution is given by

F_\kappa(x) =

1 - \exp_\kappa(-\beta x^\alpha)

valid for x \geq 0. The cumulative Weibull distribution is recovered in the classical limit \kappa \rightarrow 0.

= Survival distribution and hazard functions =

The survival distribution function of κ-Weibull distribution is given by

:S_\kappa(x) = \exp_\kappa(-\beta x^\alpha)

valid for x \geq 0. The survival Weibull distribution is recovered in the classical limit \kappa \rightarrow 0.

File:Kaniadakisweibull1.png

The hazard function of the κ-Weibull distribution is obtained through the solution of the κ-rate equation:

\frac{ S_\kappa(x) }{ dx } = -h_\kappa S_\kappa(x)
with S_\kappa(0) = 1, where h_\kappa is the hazard function:

:h_\kappa = \frac{\alpha \beta x^{\alpha-1}}{\sqrt{1+\kappa^2 \beta^2 x^{2\alpha} }}

The cumulative κ-Weibull distribution is related to the κ-hazard function by the following expression:

:S_\kappa = e^{-H_\kappa(x)}

where

:H_\kappa (x) = \int_0^x h_\kappa(z) dz

:H_\kappa (x) = \frac{1}{\kappa} \textrm{arcsinh}\left(\kappa \beta x^\alpha \right)

is the cumulative κ-hazard function. The cumulative hazard function of the Weibull distribution is recovered in the classical limit \kappa \rightarrow 0: H(x) = \beta x^\alpha .

Properties

= Moments, median and mode =

The κ-Weibull distribution has moment of order m \in \mathbb{N} given by

:\operatorname{E}[X^m] = \frac{|2\kappa \beta|^{-m/\alpha}}{1+\kappa \frac{m}{\alpha}} \frac{\Gamma\Big(\frac{1}{2\kappa}-\frac{m}{2\alpha}\Big)}{\Gamma\Big(\frac{1}{2\kappa}+\frac{m}{2\alpha}\Big)} \Gamma\Big(1+\frac{m}{\alpha}\Big)

The median and the mode are:

: x_{\textrm{median}} (F_\kappa) = \beta^{-1/\alpha} \Bigg(\ln_\kappa (2)\Bigg)^{1/\alpha}

: x_{\textrm{mode}} = \beta^{ -1 / \alpha } \Bigg( \frac{ \alpha^2 + 2 \kappa^2 (\alpha - 1 )}{ 2 \kappa^2 ( \alpha^2 - \kappa^2)}\Bigg)^{1/2 \alpha} \Bigg( \sqrt{1 + \frac{4 \kappa^2 (\alpha^2 - \kappa^2 )( \alpha - 1)^2}{ [ \alpha^2 + 2 \kappa^2 (\alpha - 1) ]^2} } - 1 \Bigg)^{1/2 \alpha} \quad (\alpha > 1)

== Quantiles ==

The quantiles are given by the following expression

x_{\textrm{quantile}} (F_\kappa) = \beta^{-1 / \alpha } \Bigg[ \ln_\kappa \Bigg(\frac{1}{1 - F_\kappa} \Bigg) \Bigg]^{1/ \alpha}
with 0 \leq F_\kappa \leq 1.

== Gini coefficient ==

The Gini coefficient is:

\operatorname{G}_\kappa = 1 - \frac{\alpha + \kappa}{ \alpha + \frac{1}{2}\kappa } \frac{\Gamma\Big( \frac{1}{\kappa} - \frac{1}{2 \alpha}\Big)}{\Gamma\Big( \frac{1}{\kappa} + \frac{1}{2 \alpha}\Big)} \frac{\Gamma\Big( \frac{1}{2 \kappa} + \frac{1}{2 \alpha}\Big)}{\Gamma\Big( \frac{1}{ 2\kappa} - \frac{1}{2 \alpha}\Big)}

== Asymptotic behavior ==

The κ-Weibull distribution II behaves asymptotically as follows:

: \lim_{x \to +\infty} f_\kappa (x) \sim \frac{\alpha}{\kappa} (2 \kappa \beta)^{-1/\kappa} x^{-1 - \alpha/\kappa}

: \lim_{x \to 0^+} f_\kappa (x) = \alpha \beta x^{\alpha - 1}

Related distributions

Applications

The κ-Weibull distribution has been applied in several areas, such as:

  • In economy, for analyzing personal income models, in order to accurately describing simultaneously the income distribution among the richest part and the great majority of the population.{{Cite journal |last1=Clementi |first1=Fabio |last2=Gallegati |first2=Mauro |last3=Kaniadakis |first3=Giorgio |date=October 2010 |title=A model of personal income distribution with application to Italian data |url=http://link.springer.com/10.1007/s00181-009-0318-2 |journal=Empirical Economics |language=en |volume=39 |issue=2 |pages=559–591 |doi=10.1007/s00181-009-0318-2 |s2cid=154273794 |issn=0377-7332}}{{Cite journal |last1=Clementi |first1=F |last2=Gallegati |first2=M |last3=Kaniadakis |first3=G |date=2012-12-06 |title=A generalized statistical model for the size distribution of wealth |url=https://iopscience.iop.org/article/10.1088/1742-5468/2012/12/P12006 |journal=Journal of Statistical Mechanics: Theory and Experiment |volume=2012 |issue=12 |pages=P12006 |doi=10.1088/1742-5468/2012/12/P12006 |arxiv=1209.4787 |bibcode=2012JSMTE..12..006C |s2cid=18961951 |issn=1742-5468}}
  • In seismology, the κ-Weibull represents the statistical distribution of magnitude of the earthquakes distributed across the Earth, generalizing the Gutenberg–Richter law,{{Cite journal |last=da Silva |first=Sérgio Luiz E.F. |date=2021 |title=κ -generalised Gutenberg–Richter law and the self-similarity of earthquakes |url=https://linkinghub.elsevier.com/retrieve/pii/S0960077920310134 |journal=Chaos, Solitons & Fractals |language=en |volume=143 |pages=110622 |doi=10.1016/j.chaos.2020.110622|bibcode=2021CSF...14310622D |s2cid=234063959 }} and the interval distributions of seismic data, modeling extreme-event return intervals.{{Cite journal |last1=Hristopulos |first1=Dionissios T. |last2=Petrakis |first2=Manolis P. |last3=Kaniadakis |first3=Giorgio |date=2014-05-28 |title=Finite-size effects on return interval distributions for weakest-link-scaling systems |url=https://link.aps.org/doi/10.1103/PhysRevE.89.052142 |journal=Physical Review E |language=en |volume=89 |issue=5 |pages=052142 |doi=10.1103/PhysRevE.89.052142 |pmid=25353774 |arxiv=1308.1881 |bibcode=2014PhRvE..89e2142H |s2cid=22310350 |issn=1539-3755}}{{Cite journal |last1=Hristopulos |first1=Dionissios |last2=Petrakis |first2=Manolis |last3=Kaniadakis |first3=Giorgio |date=2015-03-09 |title=Weakest-Link Scaling and Extreme Events in Finite-Sized Systems |journal=Entropy |language=en |volume=17 |issue=3 |pages=1103–1122 |doi=10.3390/e17031103 |bibcode=2015Entrp..17.1103H |issn=1099-4300|doi-access=free }}
  • In epidemiology, the κ-Weibull distribution presents a universal feature for epidemiological analysis.{{Cite journal |last1=Kaniadakis |first1=Giorgio |last2=Baldi |first2=Mauro M. |last3=Deisboeck |first3=Thomas S. |last4=Grisolia |first4=Giulia |last5=Hristopulos |first5=Dionissios T. |last6=Scarfone |first6=Antonio M. |last7=Sparavigna |first7=Amelia |last8=Wada |first8=Tatsuaki |last9=Lucia |first9=Umberto |date=2020 |title=The κ-statistics approach to epidemiology |journal=Scientific Reports |language=en |volume=10 |issue=1 |pages=19949 |doi=10.1038/s41598-020-76673-3 |issn=2045-2322 |pmc=7673996 |pmid=33203913|bibcode=2020NatSR..1019949K }}

See also

References

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