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Posts: 2

# Population sd and variance

Hi all,

I am learning descriptive statistics using SAS. If we consider the dataset that we are working on as a population then how to know the population sd and variance through proc univariate or proc means. well what i can see is both procedures show the sd and variance of bessels correction. (not the population) if i am correct. Thanks in advance.

Regards
Sachin K

Posts: 1,246

## Re: Population sd and variance

Hi @ksachin,

Both the PROC UNIVARIATE and the PROC MEANS (and the PROC SUMMARY) statement have a VARDEF= option, whose default value is DF (or df, "degrees of freedom," i.e. denominator n-1 in the definition of variance and related statistics such as standard deviation). Another valid value of this option is N (not case-sensitive either), which requests denominator n, as needed for calculating population variance, standard deviation, etc.

Example:

``````proc means vardef=n data=sashelp.class;
var age;
run;``````
New Contributor
Posts: 2

## Re: Population sd and variance

Posted in reply to FreelanceReinhard

hi freelancereinhard

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