Hyperbolic distribution

Hyperbolic distribution

Probability distribution
name =hyperbolic
type =density
pdf_

cdf_

parameters =mu location (real) alpha (real) eta asymmetry parameter (real) delta scale parameter (real) gamma = sqrt{alpha^2 - eta^2}
support =x in (-infty; +infty)!
pdf =frac{gamma}{2alphadelta K_1(delta gamma)} ; e^{-alphasqrt{delta^2 + (x - mu)^2}+ eta (x - mu)} K_lambda denotes a modified Bessel function of the third kind
cdf =
mean =mu + frac{delta eta K_{2}(delta gamma)}{gamma K_1(deltagamma)}
median =
mode =mu + frac{deltaeta}{gamma}
variance =frac{delta K_{2}(delta gamma)}{gamma K_1(deltagamma)} + frac{eta^2delta^2}{gamma^2}left(frac{K_{3}(deltagamma)}{K_{1}(deltagamma)} -frac{K_{2}^2(deltagamma)}{K_{1}^2(deltagamma)} ight)
skewness =
kurtosis =
entropy =
mgf =frac{e^{mu z}gamma K_1(delta (alpha^2 -(eta +z)^2))}{(alpha^2 -(eta +z)^2)K_1 (delta gamma)}
char =

The hyperbolic distribution is a continuous probability distribution that is characterized by the fact that the logarithm of the probability density function is a hyperbola. Thus the distribution decreases exponentially, which is more slowly than the normal distribution. It is therefore suitable to model phenomena where numerically large values are more probable than is the case for the normal distribution. Examples are returns from financial assets and turbulent wind speeds. The hyperbolic distributions form a subclass of the generalised hyperbolic distributions.

The origin of the distribution is the observation by Ralph Alger Bagnold in his book The Physics of Blown Sand and Desert Dunes (1941) that the logarithm of the histogram of the empirical size distribution of sand deposits tends to form a hyperbola. This observation was formalised mathematically by Ole Barndorff-Nielsen in a paper in 1977, where he also introduced the generalised hyperbolic distribution, using the fact the a hyperbolic distribution is a random mixture of normal distributions.


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Generalised hyperbolic distribution — Probability distribution name =generalised hyperbolic type =density pdf cdf parameters =mu location (real) lambda (real) alpha (real) eta asymmetry parameter (real) delta scale parameter (real) gamma = sqrt{alpha^2 eta^2} support =x in ( infty; …   Wikipedia

  • Hyperbolic secant distribution — Probability distribution name =hyperbolic secant type =density pdf cdf parameters = none support =x in ( infty; +infty)! pdf =frac12 ; operatorname{sech}!left(frac{pi}{2},x ight)! cdf =frac{2}{pi} arctan!left [exp!left(frac{pi}{2},x ight) ight] ! …   Wikipedia

  • Cauchy distribution — Not to be confused with Lorenz curve. Cauchy–Lorentz Probability density function The purple curve is the standard Cauchy distribution Cumulative distribution function …   Wikipedia

  • Student's t-distribution — Probability distribution name =Student s t type =density pdf cdf parameters = u > 0 degrees of freedom (real) support =x in ( infty; +infty)! pdf =frac{Gamma(frac{ u+1}{2})} {sqrt{ upi},Gamma(frac{ u}{2})} left(1+frac{x^2}{ u} ight)^{ (frac{… …   Wikipedia

  • Variance-gamma distribution — Probability distribution name =variance gamma distribution type =density pdf cdf parameters =mu location (real) alpha (real) eta asymmetry parameter (real) lambda > 0 gamma = sqrt{alpha^2 eta^2} > 0 support =x in ( infty; +infty)! pdf… …   Wikipedia

  • Normal-inverse Gaussian distribution — Normal inverse Gaussian (NIG) parameters: μ location (real) α tail heavyness (real) β asymmetry parameter (real) δ scale parameter (real) support …   Wikipedia

  • Normal distribution — This article is about the univariate normal distribution. For normally distributed vectors, see Multivariate normal distribution. Probability density function The red line is the standard normal distribution Cumulative distribution function …   Wikipedia

  • Maxwell–Boltzmann distribution — Maxwell–Boltzmann Probability density function Cumulative distribution function parameters …   Wikipedia

  • Probability distribution — This article is about probability distribution. For generalized functions in mathematical analysis, see Distribution (mathematics). For other uses, see Distribution (disambiguation). In probability theory, a probability mass, probability density …   Wikipedia

  • Negative binomial distribution — Probability mass function The orange line represents the mean, which is equal to 10 in each of these plots; the green line shows the standard deviation. notation: parameters: r > 0 number of failures until the experiment is stopped (integer,… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”