Estimation of polarisation angles of Q and U sources. Left panel: correlation between true and estimated angles. The coloured areas represent a confidence interval of ±29° for Q sources and ±32° U ones, which are the standard deviation of the relative error of each population, respectively. Dashed black lines are the 1:1 case. Right panel: distribution of polarisation angles for both true and estimated Q and U catalogues, with the blue areas showing the true angles and orange and green areas showing the estimated angles for Q and U sources, respectively.