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IBPPFName:
with B denoting the beta function (HELP BETA for details). The inverted beta cumulative distribution function is computed by numerically integrating the inverted beta probability density function. The percent point function is computed by numerically inverting the cumulative distribution function.
<SUBSET/EXCEPT/FOR qualification> where <p> is a variable, a number, or a parameter in the range [0,1]; <alpha> is a number or parameter specifying the first shape parameter; <beta> is a number or parameter specifying the second shape parameter; <y> is a variable or a parameter (depending on what <p> is) where the computed inverted beta ppf value is stored; and where the <SUBSET/EXCEPT/FOR qualification> is optional.
LET X2 = IBPPF(P1,A,B) PLOT IBPPF(P,0.5,2) FOR P = 0.01 0.01 0.99
"Statistical Distributions", Third Edition, Evans, Hastings, and Peacock, Wiley, 2000.
LET ALPHA = DATA 0.5 0.5 0.5 1 1 1 2 2 2 LET BETA = DATA 0.5 1 2 0.5 1 2 0.5 1 2 . XLIMITS 0 1 MAJOR XTIC MARK NUMBER 6 MINOR XTIC MARK NUMBER 1 . MULTIPLOT 3 3 MULTIPLOT CORNER COORDINATES 0 0 100 100 MULTIPLOT SCALE FACTOR 3 LOOP FOR K = 1 1 9 LET A = ALPHA(K) LET B = BETA(K) TITLE ALPHA = ^A, BETA = ^B PLOT IBPPF(P,^A,^B) FOR P = 0.01 0.01 0.99 END OF LOOP END OF MULTIPLOT
Date created: 2/3/2004 |