# Calcuulate variance for sub-groups

Hello,

I am attempting to calculate variance withing subgroups of results.

The concept is simple. In my training set, I have groups of tests. For example

Group - score

1 22

1 23

1 21

1 25

2 44

2 43

2 50

etc..

I want to calculate the variance for EACH GROUP.

I CAN easily create subgroups by using the following:

I tried using an ExampleSetTranspose as Ingo suggested in an earlier post, but this doesn't work. When I add the variance attribute to the group, RM responds with an error informing me that the subgroup number of attributes can't be changed.

Can someone help me figure out how to do this?

Thanks!!

I am attempting to calculate variance withing subgroups of results.

The concept is simple. In my training set, I have groups of tests. For example

Group - score

1 22

1 23

1 21

1 25

2 44

2 43

2 50

etc..

I want to calculate the variance for EACH GROUP.

I CAN easily create subgroups by using the following:

What I want to do is add AN attribute for variance for each of the subgroup. I tried using the AttributeAggregation operator, but it doesn't work.

<operator name="AttributeSubsetPreprocessing (2)" class="AttributeSubsetPreprocessing" expanded="no">

<parameter key="attribute_name_regex" value="group"/>

</operator>

I tried using an ExampleSetTranspose as Ingo suggested in an earlier post, but this doesn't work. When I add the variance attribute to the group, RM responds with an error informing me that the subgroup number of attributes can't be changed.

Can someone help me figure out how to do this?

Thanks!!

0

## Answers

294RM Product Managementtry aggregating the values within the group by using an [tt]Aggregation[/tt] operator and joining the resulting example sets using the group as id.

Regards,

Tobias