Chapter 8 of 12All chapters
Chapter 8 of 12
Bias and fairness
Patterns in the data become patterns in the output.
Where bias enters
A model trained on historical decisions learns the historical pattern, including the unfair parts. A hiring model trained on past hires will reproduce whoever was hired before.
- Bias can enter through the data, the labels, the objective or the deployment.
- Removing an attribute rarely helps, because other fields stand in for it.
Why it is hard
Fairness has several definitions that cannot all be satisfied at once, so a system is fair according to a choice someone made. That choice deserves to be stated rather than assumed.