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Dataplot Vol 1 Auxiliary Chapter

SRAPPF

Name:
    SRAPPF (LET)
Type:
    Library Function
Purpose:
    Compute the studentized range percent point function with degrees of freedom parameter V and number of samples parameter R.

    NOTE: This command is still being tested. Currently it does not generate correct answers.

Description:
    The studentized range is defined as:

      Q = Range/Standard Deviation

    The formula for the distribution of the studentized range is mathematically complex and not given here.

    The studentized range is used in constructing confidence intervals for tests of multiple comparisons in analysis of variance problems.

    The parameter V must be >= 1 and R must be >= 2. Note that for the most common uses of this distribution R is usually set to V + 1.

    This function is only supported for values in the range 0.90 to 0.99.

Syntax:
    LET <y> = SRAPPF(<p>,<v>,<r>)             <SUBSET/EXCEPT/FOR qualification>
    where <p> is a variable or a parameter where the studentized range percent point will be computed (0.90 <= <p> <= 0.99);
                  <y> is a variable or a parameter (depending on what <x> is) where the computed studentized range cdf values are stored;
                  <v> is a number or parameter that specifies the degrees of freedom parameter (<v> >= 1);
                  <r> is a number or parameter that specifies the sample size parameter (<r> >= 2);
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = SRAPPF(0.90,10,11)
    LET A = SRAPPF(0.95,22,23)
    LET X2 = SRAPPF(0.99,V,R)
Note:
    This command is implemented using the Algorithm AS 190, qrtrng, from Applied Statistics (1983), Vol. 32, No. 2. It incorporates modifications from Applied Statistics, (1985) Vol. 34, (1).
Note:
    Library functions are distinguished from let subcommands in the following ways.

    1. Functions enclose the input value in parenthesis. Let subcommands use spaces.
    2. Functions can accept (and return) either parameters (i.e., single values) or variables (i.e., an array of values) while let subcommands are specific in which they accept as input and what they return as output.
    3. Functions can accept expressions while let subcommands do not. For example, the following is legal:
        LET Y2 = ABS(Y1-INT(Y1))
      For let subcommands, you typically have to do something like the following:
        LET YTEMP = Y**2 + 8
        LET A = SUM YTEMP
Default:
    None
Synonyms:
    None
Related Commands:
    SRACDF = Compute the studentized range cumulative distribution function.
    ANOVA = Perform an analysis of variance.
    CHSPDF' = Compute the chi-square probability density function.
    CHSPPF = Compute the chi-square percent point function.
    CHSCDF = Compute the chi-square cumulative distribution function.
    FCDF = Compute the F cumulative distribution function.
    FPDF = Compute the F probability density function.
    FPPF = Compute the F percent point function.
    NORCDF = Compute the normal cumulative distribution function.
    NORPDF = Compute the normal probability density function.
    NORPPF = Compute the normal percent point function.
    TCDF = Compute the T cumulative distribution function.
    TPDF = Compute the T probability density function.
    TPPF = Compute the T percent point function.
Applications:
    Analysis of Variance
Implementation Date:
    1999/3
Program:
    TITLE AUTOMATIC
    MULTIPLOT CORNER COORDINATES 5 5 95 95
    MULTIPLOT 2 2
    PLOT SRAPPF(P,4,5) FOR P = 0.90 0.01 0.99
    PLOT SRAPPF(P,9,10) FOR P = 0.90 0.01 0.99
    PLOT SRAPPF(P,19,20) FOR P = 0.90 0.01 0.99
    PLOT SRAPPF(P,29,30) FOR P = 0.90 0.01 0.99
    END OF MULTIPLOT

    plot generated by sample program

Date created: 6/5/2001
Last updated: 4/4/2003
Please email comments on this WWW page to alan.heckert@nist.gov.