Inverse-gamma distribution - Factbites
 Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Inverse-gamma distribution


    Note: these results are not from the primary (high quality) database.


  
 Probability distribution - Wikipedia, the free encyclopedia
The Erlang distribution, which is a special case of the gamma distribution with integral shape parameter, developed to predict waiting times in queuing systems.
It is a special case of the Gamma distribution, and it is used in goodness-of-fit tests in statistics.
The rectangular distribution is a uniform distribution on [-1/2,1/2].
en.wikipedia.org /wiki/Discrete_distribution

  
 Gamma distribution - Wikipedia, the free encyclopedia
In probability theory and statistics, the gamma distribution is a continuous probability distribution.
where k > 0 is the shape parameter and θ > 0 is the scale parameter of the gamma distribution.
If k is an integer, the gamma distribution is an Erlang distribution (so named in honor of A.
en.wikipedia.org /wiki/Gamma_distribution

  
 Gamma Distribution
As there is no inverse probability function for the gamma distribution, some form of numerical technique has to be used.
A chi-squared distribution is a gamma distribution in which the shape parameter set to the degrees of freedom divided by two and the scale parameter set to two.
Typically, the gamma distribution is defined in terms of a scale factor and a shape factor.
www.brighton-webs.co.uk /distributions/gamma.asp

  
 The model
The conjugate prior for variance of a Gaussian is the inverse gamma distribution.
These should be written as conditional distributions conditional to the parameters of the hyperprior but the conditioning variables have been dropped out to simplify the notation.
Because of the Markov property, the prior distribution of the probabilities of the hidden states can also be written in factorial form:
www.cis.hut.fi /ahonkela/dippa/node49.html

  
 Glossary of research economics
This is a one-parameter family of distributions, and the parameter, n, is conventionally labeled the degrees of freedom of the distribution.
A diffuse prior is a distribution of the parameter with equal probability for each possible value, coming as close as possible to representing the notion that the analyst hasn't a clue about the value of the parameter being estimated.
Is the distribution of sums of squares of r standard normal variables.
econterms.com /econtent.html

  
 Stata help for probfun
This is a quick reference for the probability distribution and density functions.
invbinomial( n, k, P) returns the inverse binomial: for P < 0.5, probability p such that the probability of observing k or more successes in n trials is P ; for P >0.5, probability p such that the probability of observing k or fewer successes in n trials is 1- P.
Ftail( n1, n2, f) returns the reverse cumulative (upper-tail, survival) F distribution with n1 numerator and n2 denominator degrees of freedom.
www.stata.com /help.cgi?probfun

  
 Weekly Calendar
(Gamma and inverse gamma are clearly extreme cases of the GIG distribution, and "dual" to each other.) The work of C.C. Heyde (J.Appl.
model was introduced as direct competitor, the increment in the intrinsic time process has inverse gamma distribution.
distribution for log-increment of price was introduced by D.B. Madan and E.Seneta, Journal of Business, 63(1990)511-524, and has since found use on Wall Street.
www-math.bgsu.edu /oldcalendars/2003-10-20.html

  
 Ex-netgp-o.html
The software allows the noise variance for a case to vary according to an inverse gamma distribution.
In this synthetic data, the input variable, x, again had a standard Gaussian distribution and the corresponding target value came from a distribution with mean given by 0.3 + 0.4*x + 0.5*sin(2.7*x) + 1.1/(1+x^2) For most cases, the distribution about this mean was Gaussian with standard deviation 0.1.
This is effectively the same as letting the noise have a t-distribution rather than a Gaussian distribution.
www.cs.toronto.edu /~radford/fbm.1998-08-02.doc/Ex-netgp-o.html

  
 MCSim User' Manual
But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.
If distribution of executable or object code is made by offering access to copy from a designated place, then offering equivalent access to copy the source code from the same place counts as distribution of the source code, even though third parties are not compelled to copy the source along with the object code.
Normal distribution (two reals numbers): mean and standard deviation, the latter being stricly positive.
guinness.cs.stevens.edu /packages/mcsim/mcsim.html

  
 Mathematical Statistics with Mathematica - Index
as limit distribution of Binomial 95, 280, 300
asymptotic distribution of MLE of (m, s2) 372-374
www.mathstatica.com /book/bookindex.html

  
 Stock Assessment of Small Coastal Sharks in the U
was an inverse gamma distribution with the 10% and 90% quantiles set at 0.04 and 0.08, and the priors for
The marginal posterior distributions of the most representative parameters obtained using the two importance functions with the Prager form of the SPM are shown in Figures 5 and 6.
The marginal posterior distributions of the most representative parameters obtained using the two importance functions with the Prager form of the SPM are shown in Figures 1 and 2.
www.nmfs.noaa.gov /sfa/hms/lcs_sensitivity/Sensitivity_analysis1.asp

  
 Citations: Random Number Generation and Monte Carlo Methods - Gentle (ResearchIndex)
In this situation, it can be shown that full conditional distribution p(# 2 z i) is inverse gamma distribution with parameters #n = # 0 n (11) # 2 n = # 0 # 2 0 # i z 2 i) # 0 n) 12) Many software packages generate gamma random variables directly.
In this situation, it can be shown that full conditional distribution p (o 2 I zi) is inverse gamma distri bution with parameters vn vo rz (11) 2 (oo o n) Many software packages generate gamma random variables directly.
The simulation framework is also well suited for the analysis of issues such as optimal reserving, the distribution of the future solvency degree, and default probabilities at the individual contract level.
citeseer.ist.psu.edu /context/1232713/0

  
 Technical FAQ (1534) Is it possible to get maximum likelihood estimates from PROC NLIN? What about other procedures?
However, if the error term is assumed to have a distribution in the exponential family (this includes binomial, poisson, normal, gamma, and inverse gaussian distributions), it has been shown that an iteratively reweighted least squares approach is equivalent to maximum likelihood estimation.
For a linear model with a poisson, gamma, inverse gaussian error distribution, see PROC GENMOD.
For a linear model with a normal error distribution, see PROC MIXED or PROC GENMOD.
support.sas.com /faq/015/FAQ01534.html

  
 Halphen Distribution System. II: Parameter and Quantile Estimation
In some cases, the maximum likelihood system of equations does not allow a solution, and the limiting forms of the Halphen distributions, the gamma and inverse gamma, should alternatively be considered.
Because the Halphen distributions are members of the exponential class of distributions, parameters can be estimated from sufficient statistics, and maximum likelihood estimators should possess certain optimality characteristics.
In this paper, the second in a series of two, procedures for the estimation of parameters and quantiles of the Halphen type A, B, and IB distributions are presented.
www.pubs.asce.org /WWWdisplay.cgi?9902810

  
 A Method for Assigning Letter Grades: Multi-Curve Grading
Since the distribution is not continuous, I choose the highest letter grade whose cumulative probability is less than q.
That is, the distribution of scores is a weighted sum of several Normal distributions.
The disadvantage of Distribution Gap is that it is hard to use in practice.
alex.strashny.org /papers/Strashny03.Multi.Curve.Grading.html

  
 BAYESIAN_METHODOLOGY.doc
This means that to generate a t-random quantity, we first draw from an inverse gamma distribution.
The predictive distribution is then the mixture of all of the output distributions, representing the uncertainty due to model uncertainty and model parameter uncertainty.
Having specified the model as a full joint distribution on all quantities, whether parameters or observables, we wish to sample values of the unknown parameters from their conditional (posterior) distribution given those stochastic nodes that have been observed.
www.sksi.net /fskitea/2004VirtualWorkshop/BAYESIAN_METHODOLOGY.doc

  
 EE362 Project Report
The following experiment is conducted using the inverse gamma corrected colors from the Macbeth color images, and I compare each image under different illumination with the control image( in which the light source is not filtered).
The inverse gamma corrected images has the linear plot as show below, they are generated by verifyInverseGamma.m.
The inverse gamma correction could be done using the following:
graphics.stanford.edu /~liyiwei/project/ee362/report.html

  
 CAS- Insurance: Mathematics and Economics
The integral computed is known to have an inverse gamma distribution when stopped at a random exponential time, so it not too surprising that the authors find an inverse gamma distribution fit works well.
The simulated multivariate distributions are chosen from several different multivariate distributions including a model derived from a cubic linear regression model, a bivariate stable distribution, and a heteroscedastic linear regression.
PQD asserts that Cov(f(F(X)), g(G(Y)))>=0 for all nondecreasing f, g where F and G are the (empirical) distributions of X and Y. PFD asserts that Cov(f(F(X)), f(G(Y)))>=0 for all f.
www.casact.org /research/summaries/IMEv34-3.htm

  
 glosf.html
The Gamma distribution (the term first used by Weatherburn, 1946) is defined as:
The g2 inverse is used to find a solution to the normal equations in the general linear model; refer to the General Linear Models chapter for additional details.
In short, Gamma is also a probability ; specifically, it is computed as the difference between the probability that the rank ordering of the two variables agree minus the probability that they disagree, divided by 1 minus the probability of ties.
www.statsoft.com /textbook/glosf.html

  
 Citations: Monte Carlo implementation of Gaussian process models for Bayesian regression and classification - Neal (ResearchIndex)
We follow [16] The Laplace approach to GPC is to approximate the posterior P (y jD; by the Gaussian distribution N( y ; H Gamma1) where y = argmaxP (y jD; is the posterior mode and H = r 0 y ry ( Gamma log P (y jD;....
To compensate for the unbalanced distribution of classes, the penalty term C i was chosen to be 0.8 for the examples from the larger class and 1 for the smaller class.
This is important as the t distribution is widely used when it is desired that the noise model be robust, i.e.
citeseer.ist.psu.edu /context/30017/48373

  
 R: Nonlinear Normal, Gamma, and Inverse Gaussian Regression Models
The distribution to be used: normal, gamma, or inverse Gauss.
fits a user-specified nonlinear regression equation by least squares (normal) or its generalization for the gamma and inverse Gauss distributions.
Nonlinear Normal, Gamma, and Inverse Gaussian Regression Models
rss.acs.unt.edu /Rdoc/library/gnlm/html/nlr.html

  
 Inverse F Distribution
For generating random numbers with an F distribution, this approximation alone may be adequate.
Beware that some of the F distribution approximations in the Handbook of Mathematical Functions aren't very accurate.
What I used to do (and it worked quite well), is to find in Abramowitz and Stegun's "Handbook of Mathematical Functions" a suitable series for computing the probability given the F value, then invert using Newton iteration.
www.chilton.com /~jimw/fdist.html

  
 NMath Stats User's Guide - 5.5 Gamma Distribution
The distribution function for the gamma distribution is:
The gamma distribution is a family of curves with two free parameters, usually labelled
is large, the gamma distribution closely approximates a normal distribution.
www.centerspace.net /doc/NMath/Stats/user/distributions6.html

  
 Matlab Codes
lorenzn.m handles the coefficients p(i) and q(i), calculates the ratio of concentration, R and finally the area of concentration of a given vector X with frequency distribution specified in vector n
prtornd.m samples from a pareto distribution by means of a probit
cauchrnd.m samples from a cauchy distribution as ratio of two independent N(0,1)
www.ds.unifi.it /baio/Matlab%20Codes.html

  
 On the use of the quasi-Gaussian entropy theory in non-canonical ensembles. I. Prediction of temperature dependence of thermodynamic properties - Amadei, Apol, Berendsen (ResearchIndex)
We obtained in this way the temperature dependence of thermodynamic functions in the canonical ensemble assuming a Gaussian, Gamma or Inverse Gaussian distribution.
Abstract: In previous articles we derived and tested the quasi-Gaussian entropy theory, a description of the excess Helmholtz free energy in terms of the potential energy distribution, instead of the configurational partition function.
11 Handbook of statistical distributions (context) - Patel, Kapadia et al.
citeseer.ist.psu.edu /12709.html

  
 Bibliography
The probability density function was derived as a product of a gamma distributed complex speckle variable and the generalized inverse Gaussian distribution for terrain backscatter.
The other two parameters, which are responsible for shape and spread of the distribution, are estimated by the method of moments where the negative moments are generated by inverse transformation of the normalized SAR data.
In this paper are given reasons that the multilook G-distribution is based on three joint distributions from the Gamma family.
www.ncgia.ucsb.edu /ncrst/resources/bibliography/bibL-Z.html

  
 Statistics.com Courses: Generalized Linear Models
GLM models are all members of the exponential family of distributions, and allow the modeling of responses, or dependent variables, that take the form of counts, proportions, dichotomies (1/0), positive continuous values, as well as values that follow the normal Gaussian distribution.
Generalized Linear Models is a unified method used to extend the general linear model, or ordinary least squares (OLS) regression, to incorporate responses other than normal.
www.statistics.com /content/courses/glm/index.html

  
 Files
rf - Random numbers from the F distribution rgamma - Random numbers from the gamma distribution.
normmix - Estimate a mixture of normal distributions.
rbinom - Random numbers from the binomial distribution.
www.maths.lth.se /matstat/stixbox/Contents.html

  
 Cephes double precision special functions suite
* * This is accomplished using the inverse gamma integral * function and the relation * * m = igami( k+1, y).
* * This is accomplished using the inverse beta integral * function and the relations * * z = incbi( df2/2, df1/2, p) * x = df2 (1-z) / (df1 z).
* * This is accomplished using the inverse beta integral * function and the relation * * 1 - p = incbi( n-k, k+1, y).
cm.bell-labs.com /netlib/cephes/doubldoc.html

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.