Predicted versus true intrinsic polarization angle for a test with multiple Gaussian components generated according to Table 4. Predicted angles are shown as black, red and green markers for samples containing one, two and three peaks respectively. The range is divided into 20 bins from which the median ±25% are calculated for the full dataset, and shown as red dots and errorbars respectively. A reference line where the predicted angle equals the true angle is shown as a dashed blue line. Predictions with an error larger than π/2 radians are adjusted by ±π to account for the π-periodicity of the signal.