IGAHAZ
Name:
Type:
Purpose:
Compute the standard form of the inverted gamma hazard
function.
Description:
The standard form of the inverted gamma hazard function is:
where is
the shape parameter and IGAPDF and IGACDF are the
probability density and cumulative distribution functions of the
inverted gamma distribution.
The inverted gamma is a special case of the generalized gamma
distribution where the second shape parameter is equal to 1.
Syntax:
LET <y> = IGAHAZ(<x>,<gamma>)
<SUBSET/EXCEPT/FOR qualification>
where <x> is a positive number, parameter, or a variable;
<y> is a variable or a parameter (depending on what
<x> is) where the computed inverted gamma hazard
value is saved;
<gamma> is a positive number, parameter, or variable
that specifies the shape parameter;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
LET A = IGAHAZ(3,1.5)
LET Y = IGAHAZ(X,1.5)
PLOT IGAHAZ(X,1.5) FOR X = 5 0.1 15
Default:
Synonyms:
Related Commands:
IGACDF

= Compute the inverted gamma cumulative distribution
function.

IGAPDF

= Compute the inverted gamma probability density function.

IGAPPF

= Compute the inverted gamma percent point function.

GGDPDF

= Compute the generalized gamma probability density
function.



GAMPDF

= Compute the gamma probability density function.

WEIPDF

= Compute the Weibull probability density function.

EXPPDF

= Compute the exponential probability density function.

CHSPDF

= Compute the chisquare probability density function.

Reference:
"Continuous Univariate Distributions", 2nd. ed., Johnson, Kotz,
and Balakrishnan, John Wiley and Sons, 1994 (chapter 17).
"Statistical Distributions", 2nd. Edition, Evans, Hastings, and
Peacock, Wiley and Sons, 1993 (chapter 18).
Applications:
Implementation Date:
Program:
LET G = DATA 0.5 1 2 5
.
MULTIPLOT 2 2
MULTIPLOT CORNER COORDINATES 0 0 100 100
TITLE AUTOMATIC
LOOP FOR K = 1 1 4
LET G1 = G(K)
X1LABEL GAMMA = ^G1
PLOT IGAHAZ(X,G1) FOR X = 0.1 0.1 10
END OF LOOP
END OF MULTIPLOT
Date created: 10/9/2001
Last updated: 4/4/2003
Please email comments on this WWW page to
alan.heckert@nist.gov.
