PERCENTILE

PERCENTILE (LET)

Let Subcommand

Compute a user specified percentile for a variable.

The pth percentile of a data set is defined as that value where p percent of the data is below that value and (1-p) percent of the data is above that value. For example, the 50th percentile is the median.

LET <par> = <value> PERCENTILE <y>             <SUBSET/EXCEPT/FOR qualification>
where <y> is the response variable;
            <par> is a parameter where the computed percentile is stored;
            <value> is a parameter that specifies which percentile to compute (it is a percentage value between 0 and 100);
and where the <SUBSET/EXCEPT/FOR qualification> is optional.

LET A = 20 PERCENTILE Y
LET A = 50 PERCENTILE Y SUBSET TAG > 2

Support for the percentile has been added to the following plots:
PERCENTILE PLOT
BOOTSTRAP PERCENTILE PLOT
JACKNIFE PERCENTILE PLOT
CROSS TABULATE PERCENTILE PLOT
INTERACTION PERCENTILE PLOT


The specific percentile to compute is specified by entering the following command (before the plot command):

LET P100 = <value>

where <value> is the desired percentile.

None

None

MEDIAN	= Compute the median.
LOWER QUARTILE	= Compute the lower quartile.
UPPER QUARTILE	= Compute the upper quartile.
FIRST DECILE	= Compute the first decile (the 10th percentile).
... STATISTIC PLOT	= Generate a statistic versus subset plot for numerous statistics.

Data Analysis

1998/12

LET Y1 = NORMAL RANDOM NUMBERS FOR I = 1 1 100
LET A1 = 30 PERCENTILE Y1