Glossary term
Log Loss
A forecasting accuracy score that punishes confident wrong calls severely; a companion to the Brier Score that Closelook uses alongside it.
Log Loss is a forecasting accuracy score that penalizes confident wrong predictions far more harshly than tentative ones, because the penalty grows toward infinity as a confident forecast approaches certainty on the wrong outcome. It is a companion to the Brier Score, and Closelook uses both because they weight errors differently. Log loss is especially unforgiving of the overconfidence that destroys forecasting records. See Brier Score and Prediction Markets 101.