Visualisation of diluted AGB final surface abundances set of Monash (black circles, dilution increments of 0.01 instead of 0.002 to improve the visibility of the figure) and subset of 28 Ba stars (blue stars). Principal component analysis (see text for explanation) was used to reduce the dimensions of the AGB final surface abundances sets and derive abundances to only two linearly uncorrelated dimensions, x1 and x2, that do not have a physical meaning. For one star, BD −14°2678 (blue diamond), we plotted the results of Monte Carlo sampling of the error bars on the abundances (red circles, showing 500 samples), for details see Sect. 3.3.