# [SOLVED] Average/deviation by group

andreister
Member Posts:

**2**Contributor I
I have a data set where one of the columns is category. And I want to calculate the mean and standard deviation of some other column, but separately for each category.

Ie., for input like

GroupName...Value

A.......................1

A.......................3

B......................1

B.......................5

I want the output like

GroupName...Value...Mean...StdDev

A.......................1...........2...........1.44

A.......................3...........2...........1.44

B.......................1...........3...........2.8

B.......................5...........3...........2.8

I know how to get the group means and standard deviations via Aggregate operator, but I dont know how to add the new columns to the original dataset. What am I missing?

Thanks!

Ie., for input like

GroupName...Value

A.......................1

A.......................3

B......................1

B.......................5

I want the output like

GroupName...Value...Mean...StdDev

A.......................1...........2...........1.44

A.......................3...........2...........1.44

B.......................1...........3...........2.8

B.......................5...........3...........2.8

I know how to get the group means and standard deviations via Aggregate operator, but I dont know how to add the new columns to the original dataset. What am I missing?

Thanks!

0

## Answers

1,869UnicornBest regards,

Marius

2Contributor II put "inner" join and selected my grouping attribute for both left and right subsets, works like a charm.

1,869Unicorn