Date: Tue, 26 Oct 2021 16:16:14 +0000 (GMT) Message-ID: <1883865087.55954.1635264974552@9c5033e110b2> Subject: Exported From Confluence MIME-Version: 1.0 Content-Type: multipart/related; boundary="----=_Part_55953_544885314.1635264974552" ------=_Part_55953_544885314.1635264974552 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Content-Location: file:///C:/exported.html VAR Function

# VAR Function

Computes the variance among all values in a column. Input c= olumn can be of Integer or Decimal. If no numeric values are detected = in the input column, the function returns  `0`

The variance of a set of values attempts to measur= e the spread in values around the mean. A variance of zero means that all v= alues are the same, and a small variance means that the values are closely = bunched together. A high value for variance indicates that the numbers are = spread out widely. Variance is always a positive value.

Var(X) =3D [Sum ((X - mean(X))2)] / Count(X)

Variance comes in two flavors: population variance and sample variance.<= /p>

• Population variance computes the variance from all pos= sible values.
• Sample variance computes from a subset or sample of al= l values.
• Since Trifacta=C2=AE has = access to all available values, the computation for population variance is = used across the entire dataset.

The square root of variance is standard deviation, which is used to meas= ure variance under the assumption of a bell curve distribution. See STDEV Function.

If a row contains a missing or null value, it is not factored into= the calculation.

For a version of this function computed over a rolling window of r= ows, see ROLLINGVAR Func= tion.

## Basic Usage

=20

pivot value:VAR(myRating) group:postal_code limit= :1

Output: Generates a new table containing the unique val= ues of the `postal_code` column and the variance of the group of= values from the `myRating` column for the ```posta= l_code``` value. The `limit` parameter define= s the maximum number of output columns.

## Syntax a= nd Arguments

=20

pivot value:VAR(function_col_<= /span>ref) [group:group_col_ref] [lim= it:limit_count]

=20 =20 =20 =20 =20
Argument Required? Data Type Description
function_col_ref Y string Name of column to which to apply the funct= ion

For more information on the `group` and ```limit= ``` parameters, see Pivot Transform.

For more information on syntax standards, see Language Documentation Syntax Note= s.

### function_col_ref

Name of the column the values of which you want to calculate the varianc= e. Column must contain Integer or Decimal values.

• Literal values are not supported as inputs.
• Multiple columns and wildcards are not supported.

Usage Notes:

=20 =20 =20 =20
Required? Data Type Example Value
Yes String (column reference) `myValues`

## Examples<= /h2> Tip: For additional examples, see Common Tasks. This example illustrates how you can apply statistical functions = to your dataset. Calculations include average (mean), max, min, standard de= viation, and variance. Source:Students took a test and recorded the following scores. You want to perf= orm some statistical analysis on them: Student Score Anna 84 Ben 71 Caleb 76 Danielle 87 Evan 85 Faith 92 Gabe 85 Hannah 99 Ian 73 Jane 68 Transform:You can use the following transforms to calculate the average (mean), mi= nimum, and maximum scores:=20 derive type:single value:AVERAGE(Sco= re) as:'avgScore'=20 derive type:single value:MIN(Score)<= span> as:'minScore'=20 derive type:single value:MAX(Score)<= span> as:'maxScore'To apply statistical functions to your data, you can use the ```= VAR``` and `STDEV` functions, which can be used as the = basis for other statistical calculations. =20 derive type:single value:VAR(Score)<= /span>=20 derive type:single value:STDEV(Score= )For each score, you can now calculate the variation of each one from the= average, using the following:=20 derive type:single value:((Score - a= vg_Score) / stdev_Score) as:'stDevs'Now, you want to apply grades based on a formula: Grade standard devi= ations from avg (stDevs) A stDevs > 1 B stDevs > 0.5 C -1 <=3D stDevs <=3D 0.5 D stDevs < -1 F stDevs < -2 You can build the following transform using the `IF`&nbs= p;function to calculate grades.=20 derive type:single value:IF((stDevs = > 1),'A',IF((stDevs < -2),'F',IF((stDevs < -1),'D',IF((stDevs >= 0.5),'B','C'))))For more information, see IF = Function.To clean up the content, you might want to apply some formatting to= the score columns. The following reformats the `stdev_Score` an= d `stDevs` columns to display two decimal places:=20 set col:stdev_Score value:NUMFORMAT(stdev_Score, = '##.00')=20 set col:stDevs value:NUMFORMAT(stDevs, '##.00')=20 derive type:single value:MODE(Score)= as:'modeScore'Results: Student Score modeScore avgScore minScore maxScore var_Score stdev_Score stDevs Grade Anna 84 85 82 68 99 87.00000000000001<= /p> 9.33 0.21 C Ben 71 85 82 68 99 87.00000000000001 9.33 -1.18 D Caleb 76 85 82 68 99 87.00000000000001 9.33 -0.64 C Danielle 87 85 82 68 99 87.00000000000001 9.33 0.54 B Evan 85 85 82 68 99 87.00000000000001 9.33 0.32 C Faith 92 85 82 68 99 87.00000000000001 9.33 1.07 A Gabe 85 85 82 68 99 87.00000000000001 9.33 0.32 C Hannah 99 85 82 68 99 87.00000000000001 9.33 1.82 A Ian 73 85 82 68 99 87.00000000000001 9.33 -0.96 C Jane 68 85 82 68 99 87.00000000000001 9.33 -1.50 D =20 =20 See Also:=20 =20 =20 =20 Page:= =20 =20 =20 MAX Function=20 =20 =20 =20 Page:= =20 =20 =20 VAR Function=20 =20 =20 =20 Page:= =20 =20 =20 LISTUNIQUE F= unction=20 =20 =20 =20 Page:= =20 =20 =20 Enriching Data=20 =20 =20 =20 Page:= =20 =20 =20 COUNT Function=20 =20 =20 =20 Page:= =20 =20 =20 Create Aggre= gations=20 =20 =20 =20 Page:= =20 =20 =20 COUNTIF Functio= n=20 =20 =20 =20 Page:= =20 =20 =20 LIST Function= =20 =20 =20 =20 Page:= =20 =20 =20 MIN Function=20 =20 =20 =20 Page:= =20 =20 =20 MODEIF Function<= /a>=20 =20 =20 =20 Page:= =20 =20 =20 MODE Function= =20 =20 =20 =20 Page:= =20 =20 =20 COUNTDIST= INCT Function=20 =20 =20 =20 Page:= =20 =20 =20 Aggregate Fu= nctions=20 =20 =20 =20 Page:= =20 =20 =20 COUNTA Function<= /a>=20 =20 =20 =20 Page:= =20 =20 =20 SUMIF Function=20 =20 =20 =20 =20

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