SED navigation bar go to SED home page go to Dataplot home page go to NIST home page SED Home Page SED Staff SED Projects SED Products and Publications Search SED Pages
Dataplot Vol 2 Vol 1

PERCENT AGREE

Name:
    PERCENT AGREE (LET)
Type:
    Let Subcommand
Purpose:
    Compute the percentage of values that agree in two response variables. This is pairwise agreement (i.e., how often does Y1(I) = Y2(I) for I = 1, ..., N).
Description:
    Given two methods (or two labortories), it may sometimes be useful to know how often they reach the same conclusion.

    For example, if we have two sensors that either detect or do not detect the presence of some quantity of interest, how often do the two detectors agree?

    This command is typically used when there a discrete number of values for the variable. Often this will be two (e.g., Yes/No type data), but it is not restricted to two.

    If you want to compare values for two response variables when the data is continuous, the YOUDEN PLOT is recommended.

Syntax:
    LET <par> = PERCENT AGREE <y1> <y2>             <SUBSET/EXCEPT/FOR qualification>
    where <y1> is the first response variable;
                <y2> is the second response variable;
                <par> is a parameter where the percent agree is saved;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = PERCENT AGREE Y1 Y2
    LET A = PERCENT AGREE Y1 Y2 SUBSET TAG > 1
Note:
    Dataplot statistics can be used in a number of commands. For details, enter

Default:
    None
Synonyms:
    None
Related Commands: Applications:
    Categorical Data Analysis
Implementation Date:
    2011/7
Program:
     
    .  Step 1: Read the Data
    .
    .          Column 1: Method 1 (low  => live cell, high => dead cell)
    .          Column 2: Method 2 (high => live cell, low  => dead cell)
    .
    dimension 40 columns
    read percmat  intensity
      7.1             39.8
      8.5             29.6
     72.7              4.2
     32.3             12.3
      5.4             21.5
     71.1              4.4
    100.0             13.5
     55.0             22.4
     15.0             25.9
      8.7             38.5
      0.9             16.6
     19.0             48.5
    100.0              4.3
    100.0              7.9
      5.2             42.6
     21.8             47.2
     90.0              1.0
      2.0             23.5
     98.0              2.2
    100.0              6.2
    100.0              2.0
    100.0              5.6
    100.0              3.0
     30.0             14.3
    100.0              1.0
    end of data
    .
    .  Step 3: Generate fluctuation plot based on different levels of
    .          the 2 methods
    .
    .          Use intensity levels of 5%, 10%, 15%, 20%, 25%
    .          Use percent matching levels of 80%, 90%, 95%, 99.5%
    .
    let n = size intensity
    let intcut = data 5 10 15 20 25
    let nint = size intcut
    let matcut = data 80 90 95 99.5
    let nmat = size matcut
    .
    let int2 = intensity
    let mat2 = percmat
    let xgroup = 1 for i = 1 1 n
    let ygroup = 1 for i = 1 1 n
    let icnt = 0
    .
    loop for k = 1 1 nint
        let acut = intcut(k)
        loop for l = 1 1 nmat
            let bcut = matcut(l)
            let icnt = icnt + 1
            if icnt = 1
               let xgroupal = xgroup
               let ygroupal = ygroup
               let intcor = 0 for i = 1 1 n
               let intcor = 1 subset int2 >  acut
               let intall = intcor
               let matcor = 0 for i = 1 1 n
               let matcor = 1 subset mat2 < bcut
               let matall = matcor
            else
               let xgroup2 = k for i = 1 1 n
               extend xgroupal xgroup2
               let ygroup2 = l for i = 1 1 n
               extend ygroupal ygroup2
               let intcor = 0 for i = 1 1 n
               let intcor = 1 subset int2 >  acut
               extend intall intcor
               let matcor = 0 for i = 1 1 n
               let matcor = 1 subset mat2 < bcut
               extend matall matcor
            end of if
        end of loop
    end of loop
    .
    label case asis
    tic mark label case asis
    title case asis
    title offset 2
    .
    title Percent Agreement Between Method 1 and Method 2
    y1label Method 1
    x1label Method 2
    tic offset units data
    xlimits 1 nmat
    major xtic mark number nmat
    minor xtic mark number 0
    xtic mark offset 0.7 0.7
    x1tic mark label format alpha
    x1tic mark label content 80% 90% 95% 99.5%
    ylimits 1 nint
    major ytic mark number nint
    minor ytic mark number 0
    ytic mark offset 0.7 0.7
    y1tic mark label format alpha
    y1tic mark label content 5% 10% 15% 20% 25%
    .
    let ylevel = data 60 70 80 85 90 101
    .
    let string color = g90 g20 green cyan blue orange red
    line color ^color
    region fill color ^color
    region border color ^color
    .
    set fluctuation plot floor 0
    set fluctuation plot ceiling  100
    fluctuation percent agreement contour plot ...
                intall matall xgroupal ygroupal ylevel
    .
    box fill pattern solid
    box shadow hw 0 0
    .
    box fill color g20
    box 86 90 90 86 
    move 91 87; text <= 60
    .
    box fill color green
    box 86 86 90 82 
    move 91 83; text 60 - 70
    .
    box fill color cyan
    box 86 82 90 78 
    move 91 79; text 70 - 80
    .
    box fill color blue
    box 86 78 90 74 
    move 91 75; text 80 - 85
    .
    box fill color orange
    box 86 74 90 70 
    move 91 71; text 85 - 90
    .
    box fill color red
    box 86 70 90 66 
    move 91 67; text > 90
        
    plot generated by sample program

Privacy Policy/Security Notice
Disclaimer | FOIA

NIST is an agency of the U.S. Commerce Department.

Date created: 07/28/2011
Last updated: 10/07/2016

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