∑ n = 0 p − 1 h n u k − n {\displaystyle \sum _{n=0}^{p-1}h_{n}u_{k-n}}
σ x = 1 N − 1 ∑ i = 1 N ( x − x ¯ ) 2 {\displaystyle \sigma _{x}={\sqrt {{\frac {1}{N-1}}\sum _{i=1}^{N}(x-{\bar {x}})^{2}}}}
σ x = N ∑ i = 1 N x i 2 − ( ∑ i = 1 N x ) 2 N ( N − 1 ) {\displaystyle \sigma _{x}={\sqrt {\frac {N\sum _{i=1}^{N}x_{i}^{2}-(\sum _{i=1}^{N}x)^{2}}{N(N-1)}}}}
