0 1 2 3 4 5 6 0 0 1 2 3 4 0 Probability Random Variable ν = 1 ν = 3, (ξ = 1/3) ν = 3, ξ = 1 ν = 4, (ξ = 1/4) ν = 5, (ξ = 1/5) Inverse Chi Squared Distribution PDF