Contour solution of the joint (p,β) distribution of the Alauda family (top left), the deconvoluted smoothing of the same solution (top right), and the normalized marginal distributions for p (middle) and β (bottom). The black solid curve (sinβ) depicts the curve shape of a constant level of spin distribution on the sphere. Deconvolution is not used for the marginal distributions in order to avoid the loss of information in the smoothing.