From: Error margin analysis for feature gene extraction
y = -1
y = 1
i ∈ [1, 20]
p i (x) = G(x | μ i , σ i ) where
μ i = 0.3 - i 0.05/20,
σ i = 0.15 - i 0.05/20
p i (x) = G(x | α i , β i ) where
α i = 0.7 - i 0.05/20,
β i = 0.15 - i 0.05/20
i ∈ [21, 500]