Dataplot Vol 2 Vol 1

# RATIO OF

Name:
RATIO OF <STAT> (LET)
Type:
Let Subcommand
Purpose:
Compute the ratio of a user specified statistic for two response variables.
Description:
When comparing the scale statistics of two response variables, it is common to compare the ratio of the statistics rather than the difference. For example, given the variables Y1 and Y2, the command

LET R = RATIO OF STANDARD DEVIATION Y1 Y2

is equivalent to entering

LET S1 = STANDARD DEVIATION Y1
LET S2 = STANDARD DEVIATION Y2
LET R = S1/S2

The advantage of using the RATIO OF command is that you can use the ratio statistic in commands such as the BOOTSTRAP PLOT and STATISTIC PLOT.

The statistic specified in the RATIO OF command must be one that is computed for a single response variable (e.g., the CORRELATION statistic is not supported by this command). Although the RATIO OF command was motivated by scale statistics, it can be used for any supported statistic for a single response variable.

Syntax:
LET <par> = RATIO OF <stat> <y>
<SUBSET/EXCEPT/FOR qualification>
where <stat> is one of Dataplot's supported statistics for a single response variable;
<y> is the response variable;
<par> is a parameter where the computed ratio is saved;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
LET A = RATIO OF STANDARD DEVIATIONS Y1 Y2
LET A = RATIO OF STANDARD DEVIATIONS Y1 Y2 SUBSET Y2 > 0
LET A = RATIO OF MEDIAN ABSOLUTE DEVIATIONS Y1 Y2
LET A = RATIO OF RANGE Y1 Y2
LET A = RATIO OF INTERQUARTILE RANGE Y1 Y2
Note:
Dataplot statistics can be used in a number of commands. For details, enter

Default:
None
Synonyms:
None
Related Commands:
 BOOTSTRAP PLOT = Generate a bootstrap plot. RANGE = Compute the range of a variable. STANDARD DEVIATION = Compute the standard deviation of a variable. VARIANCE = Compute the variance of a variable.
Applications:
Statistics
Implementation Date:
2023/08
Program:

SKIP 25
RETAIN Y2 SUBSET Y2 >= 0
.
BOOTSTRAP SAMPLES 10000
BOOTSTRAP RATIO OF MEDIAN ABSOLUTE DEVIATION PLOT Y1 Y2

The following output is generated


Bootstrap Analysis for the MEDIAN ABSOLUTE DEVIATION

Response Variable One: Y1
Response Variable Two: Y2

Number of Bootstrap Samples:                      10000
Number of Observations:                              79
Mean of Bootstrap Samples:                      1.02095
Standard Deviation of Bootstrap Samples:        0.27222
Median of Bootstrap Samples:                    1.00000
Minimum of Bootstrap Samples:                   0.50000
Maximum of Bootstrap Samples:                   2.50000

Percent Points of the Bootstrap Samples
-----------------------------------
Percent Point               Value
-----------------------------------
0.1    =        0.50000
0.5    =        0.60000
1.0    =        0.60000
2.5    =        0.66667
5.0    =        0.75000
10.0    =        0.80000
20.0    =        0.80000
50.0    =        1.00000
80.0    =        1.25000
90.0    =        1.33333
95.0    =        1.33333
97.5    =        1.66667
99.0    =        2.00000
99.5    =        2.50000
99.9    =        2.50000

Percentile Confidence Interval for Statistic

------------------------------------------
Confidence          Lower          Upper
Coefficient          Limit          Limit
------------------------------------------
50.00        0.80000        1.00000
75.00        0.80000        1.33333
90.00        0.75000        1.33333
95.00        0.66667        1.66667
99.00        0.60000        2.50000
99.90        0.50000        2.50000
------------------------------------------


Date created: 08/28/2023
Last updated: 08/28/2023