1Hardgeneral⏱ 45sWhy does the bias-variance tradeoff matter when choosing model complexity?📎▼ABias and variance always move in the same directionBIncreasing model complexity typically reduces bias (better fit to training data) but increases variance (sensitivity to training data fluctuations), so an optimal complexity balances both to minimize total generalization errorCBias only matters for linear modelsDVariance is irrelevant once you have enough data