`groupdiff_tau()`

computes \(min(x/y, y/x)\), i.e. the smallest symmetric ratio between \(x\) and eqny
that is smaller than 1. If \(x\) is a vector, the symmetric ratio between all
elements in \(x\) is computed.

`groupdiff_absdiff()`

computes \(max(abs(x-y, y-x))\), i.e. the smallest absolute difference
between \(x\) and \(y\).
If \(x\) is a vector, the symmetric absolute difference between all elements in \(x\) is computed.

## Arguments

- x
(

`numeric()`

)

Measured performance in group 1, 2, ...

## Protected Attributes

The protected attribute is specified as a `col_role`

in the corresponding `Task()`

:`<Task>$col_roles$pta = "name_of_attribute"`

This also allows specifying more than one protected attribute,
in which case fairness will be considered on the level of intersecting groups defined by all columns
selected as a predicted attribute.