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Function Reference: stbllike

statistics: nlogL = stbllike (params, x)
statistics: [nlogL, acov] = stbllike (params, x)
statistics: [nlogL, acov] = stbllike (params, x, freq)

Negative log-likelihood for the stable distribution.

nlogL = stbllike (params, x) returns the negative log-likelihood of the data in x corresponding to the stable distribution, in the Nolan S0 parameterization, with (1) tail index alpha, (2) skewness beta, (3) scale gam, and (4) location delta given in the four-element vector params.

[nlogL, acov] = stbllike (params, x) also returns the inverse of the observed Fisher information matrix, acov. If the input parameter values in params are the maximum likelihood estimates, the diagonal elements of acov are their asymptotic variances. acov is based on the numerically evaluated Hessian of the negative log-likelihood, since the stable density has no closed form.

[…] = stbllike (params, x, freq) accepts a frequency vector, freq, of the same size as x. freq must contain non-negative integer frequencies for the corresponding elements in x. By default, or if left empty, freq = ones (size (x)).

Further information about the stable distribution can be found at https://en.wikipedia.org/wiki/Stable_distribution

See also: stblfit, stblpdf, stblcdf, stblinv, stblrnd

Source Code: stbllike

Negative log-likelihood of a stable fit to simulated data

 rand ("seed", 42);
 x = stblrnd (1.5, 0.5, 1, 0, 150, 1);
 phat = stblfit (x);
 nlogL = stbllike (phat, x)
nlogL = 289.58