Tag cross-validation

p-values are commonly used to determine if an effect is statistically significant. Cohen's D gives a measure of how important an effect is. It is possible to see a statistically significant difference (p value small) even if the effect isn't...

Goodhart's law claims "When a measure becomes a target, it ceases to be a good measure". This article explores how bad metrics can create perverse incentives, and how cross-validation fails to catch our errors.