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Dataplot Vol 1 Vol 2

NORMAL PLOT

Name:
    NORMAL PLOT
Type:
    Graphics Command
Purpose:
    Generates a normal plot.
Description:
    A normal plot is a normal probability plot, but with the data on the horizontal axis and neat probability values on the vertical axis. The plot consists of the following 4 components:

    1. The raw data;
    2. A fitted line to the raw data;
    3. A horizontal 50% line;
    4. A vertical 50% line.

    The characteristics of these components are controlled through the LINE and CHARACTER commands.

    If you have groups in the data, you can specify a "highlight" option to draw the points in the different groups with different attributes. For example, this can be used to draw outliers in a different color.

Syntax 1:
    NORMAL PLOT <y>             <SUBSET/EXCEPT/FOR qualification>
    where <y> is a response variable;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Syntax 2:
    NORMAL PLOT <y> <tag>             <SUBSET/EXCEPT/FOR qualification>
    where <y> is a response variable;
                <tag> is a censoring variable (values equal to 0 are omitted from the plot);
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Syntax 3:
    HIGHLIGHT NORMAL PLOT <y> <x>
                            <SUBSET/EXCEPT/FOR qualification>
    where <y> is a response variable;
                <x> is a group-id variable;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Syntax 4:
    HIGHLIGHT NORMAL PLOT <y> <tag> <x>
                            <SUBSET/EXCEPT/FOR qualification>
    where <y> is a response variable;
                <x> is a group-id variable;
                <tag> is a censoring variable (values equal to 0 are omitted from the plot);
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    NORMAL PLOT Y1
    NORMAL PLOT Y1 CENSOR
    HIGHLIGHT NORMAL PLOT Y1 X
Note:
    The following internal parameters are saved after a NORMAL PLOT. These parameters can be used like any user created parameter by the analyst.

      SIGMA - the slope of the fitted line
      MU - the intercept of the fitted line
      SDSIGMA - the standard deviation of SIGMA
      SDETA - the standard deviation of MU
      BPT1 - the 0.1% point of the best fit distribution
      BPT5 - the 0.5% point of the best fit distribution
      BP1 - the 1% point of the best fit distribution
      BP5 - the 5% point of the best fit distribution
      BP10 - the 10% point of the best fit distribution
      BP20 - the 20% point of the best fit distribution
      BP50 - the 50% point of the best fit distribution
      BP80 - the 80% point of the best fit distribution
      BP90 - the 90% point of the best fit distribution
      BP95 - the 95% point of the best fit distribution
      BP99 - the 99% point of the best fit distribution
      BP995 - the 99.5% point of the best fit distribution
      BP999 - the 99.9% point of the best fit distribution
Note:
    Some sources reverse the role of the x and y axes as used by Dataplot. You can reverse the axes in Dataplot with the command

      SET NORMAL PLOT AXES REVERSE

    To reset the default, enter

      SET NORMAL PLOT AXES DEFAULT
Default:
    None
Synonyms:
    SUBSET is a synonym for HIGHLIGHT
Related Commands: Applications:
    Exploratory Data Analysis, Distributional Modeling
Implementation Date:
    1990/05
    2011/02: Added support for HIGHLIGHT option
    2014/07: Added the SET NORMAL PLOT AXES option
Program:
    SKIP 25
    READ ZARR13.DAT Y
    LINE SOLID DASH DOT DOT
    TITLE AUTOMATIC
    NORMAL PLOT Y
        
    plot generated by sample program
Date created: 01/31/2015
Last updated: 12/04/2023

Please email comments on this WWW page to alan.heckert@nist.gov.