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Dataplot Vol 2 Vol 1

WEIGHTED SUM OF SQUARES

Name:
    WEIGHTED SUM OF SQUARES (LET)
Type:
    Let Subcommand
Purpose:
    Compute the weighted sum of squares of a variable.
Description:
    The weighted sum of squares is defined as

      WSS = SUM[i=1 to N][W(i)*X(i)**2]

    where X is the response variable and W is the weights variable. The response variable and weights variable must have the same number of observations.

    For this command, the weights are not normalized. However, at least one of the weights must be positive and none of the weights can be negative. Otherwise, an error message is reported.

Syntax:
    LET <par> = WEIGHTED SUM OF SQUARES<x> <w>
                            <SUBSET/EXCEPT/FOR qualification>
    where <x> is the response variable;
                <w> is the weights variable;
                <par> is a parameter where the weighted sum of squares is saved;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = WEIGHTED SUM OF SQUARES Y1 WEIGHT
    LET A = WEIGHTED SUM OF SQUARES Y1 WEIGHT SUBSET Y1 > 0
Note:
    Dataplot statistics can be used in a number of commands. For details, enter

Default:
    None
Synonyms:
    None
Related Commands: Applications:
    Data Analysis
Implementation Date:
    2012/06
Program:
     
    LET Y = DATA 2 3 5 7 11 13 17 19 23
    LET W = DATA 1 1 0 0 4 1 2 1 0
    .
    LET A = WEIGHTED SUM OF SQUARES Y W
        
    The returned value is 1605.

Date created: 06/29/2012
Last updated: 06/29/2012
Please email comments on this WWW page to alan.heckert@nist.gov.