Philosophy of Applied Ethics

SDS 410

Ben Baumer and Sarah Susnea

Mar 5, 2025

An Impossibility Theorem

Generally, it is not possible to simultaneously satisfy these three statistical criteria for fairness (Kleinberg et al. 2016):

  • balance for the negative class
  • balance for the positive class
  • well-calibration
  • What does this mean for algorithmic fairness?

Branches of Ethics

The Situation

Imagine you’ve been waiting in a long lunch line at one of the dining halls. You’re up next to grab a plate when someone cuts in front of you. They turn to you and explain they have a meeting they need to run to in 10 minutes.

  • How would each of the branches of applied ethics inform your response to this scenario?

Consequentialism

  • What we consider moral depends on the consequences of an action
  • An action is moral if it makes the world better in the future

A consequentialist might challenge the line cutter because although they immediately improved their future, they simultaneously worsened the futures of all the people behind them.

Deontology

  • What we consider moral depends on if that action follows social rules
  • An action is moral if the actor’s intentions were good, regardless of the consequences

A deontologist might challenge the line cutter because their actions didn’t follow the established social rules of waiting for your turn.

Virtue Ethics

  • What we consider moral depends on the actor’s character and virtue
  • An action is moral if virtues guided the actor in making the choice—people should aim to be virtuous.
  • Virtues include discipline, selflessness, justice, and honesty

A virtue ethicist guided by selflessness, you might let the line cutter go ahead. (If you centered a different virtue, you may consider acting differently.)

Your turn

  • On the back of your sheet, you have been assigned a branch of applied ethics
  • Find your like-minded teammates and split up into two groups
  • First, discuss the question about which statistical criteria for fairness you would prioritize
  • Next, apply your ethical philosophy to the COMPAS algorithm. Is it ethical? If not, how might you change it?

References

Kleinberg, Jon, Sendhil Mullainathan, and Manish Raghavan. 2016. “Inherent Trade-Offs in the Fair Determination of Risk Scores.” arXiv Preprint arXiv:1609.05807. https://arxiv.org/abs/1609.05807/.