Inferred amplitude (left panel) and phase angle (right panel) for the m = 1 classical warp model using the young giants sample (orange/brown markers) and the Cepheids sample (blue/light blue markers) based on different approaches. Individual points show the results of the m=1 tilted ring model, while solid lines correspond to the parametric fit, performed on a star-by-star basis, of the twisted line-of-nodes for the young giant (in brown) and Cepheid (in blue) samples. Orange (light blue) transparent lines represent 5 000 random realisations of the MCMC chain for the fits of the young giant (Cepheid) sets.