pdf for the mixture variable X =α
with sub-Gaussian sources at θ
=Π/ 2 (left) and at θ=θ
±δθ (right). Note that, when θ=Π/2 the pdf corresponds to the source S2, on the other side, when a perturbation on the mixing parameter θ is considered, i.e. θ=θ0±δθ, a pdf with a shape closer to the Gaussian one is obtained. It is also noted that in the intervals () the pdf f
(x;θ) attains its minimum (maximum) at θ=Π/2.