Comparison of the fit of the bi-Gaussian mixture model and the Gaussian mixture model to real asymmetric peaks. (a) The ion trace at m/z = 446.8913. (b) The ion trace at m/z = 301.1409. Colored curves: fitted components; black curve: summation of the signal from all the components. Upper-panel: the bi-Gaussian mixture fit; lower-panel: the Gaussian mixture fit.