Konubinix' opinionated web of thoughts

Loi De Goodhart

Fleeting

See this article that presents the concept quite well (to my mind).

lorsqu’une mesure devient un objectif, elle cesse d’être une bonne mesure, car elle devient sujette à des manipulations, directes (trucage des chiffres) ou indirectes (travailler uniquement à améliorer cette mesure)

https://fr.wikipedia.org/wiki/Loi_de_Goodhart

In my mind, to apply this maxim appropriately, one should differentiate between instrumental objective and final objective.

Indeed, to me, there is nothing wrong with setting instrumental objectives, as long as we keep in mind that those are simple steps to fulfill a final objective.

When the instrumental objective stops being appropriate in satisfying the final objective, I think is stops becoming useful and should be reassessed. Therefore, to me the problem of measure that becomes an objective here is the symptom of people forgetting that the objective was instrumental and consider it as a final one.

As a conclusion, I would precise that a measure the becomes an instrumental goal may still be a good measure, if the goal is explicitly stated as being instrumental. If otherwise, a measure becomes a final goal, it forgets why the measure was setup in the first place and stops being a good measure.

lorsqu’un outil devient un objectif, il cesse d’être un bon outil

lorsqu’une méthode devient un objectif, elle cesse d’être une bonne méthode

lorsqu’un objectif instrumental est utilisé comme un objectif final, il sert d’être un bon objectif instrumental

Notes linking here