
IBPDFName:
with B denoting the beta function (HELP BETA for details).
<SUBSET/EXCEPT/FOR qualification> where <x> is a variable, a number, or a parameter; <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 <x> is) where the computed inverted beta pdf value is stored; and where the <SUBSET/EXCEPT/FOR qualification> is optional.
LET X2 = IBPDF(X1,A,B) PLOT IBPDF(X,0.5,2) FOR X = 0.01 0.01 10
You can generate random numbers from an inverted beta distribution with the following command:
LET BETA = <value> LET Y = INVERTED BETA RANDOM NUMBERS FOR I = 1 1 N
"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 . MULTIPLOT 3 3 MULTIPLOT CORNER COORDINATES 0 0 100 100 MULTIPLOT SCALE FACTOR 3 LOOP FOR K = 1 1 9 LET A1 = ALPHA(K) LET B1 = BETA(K) TITLE ALPHA = ^A1, BETA = ^B1 PLOT IBPDF(X,A1,B1) FOR X = 0.01 0.01 10 END OF LOOP
Date created: 2/3/2004 