r ( d ) = ∑ i ( ( x i − μ ) ( x i + d ′ − μ ′ ) ) ∑ i ( x i − μ ) 2 ∑ i ( x i + d ′ − μ ′ ) {\displaystyle r(d)={\frac {\textstyle \sum _{i}((x_{i}-\mu )(x'_{i+d}-\mu '))}{\textstyle {\sqrt {\sum _{i}(x_{i}-\mu )^{2}}}{\sqrt {\sum _{i}(x'_{i+d}-\mu ')}}}}}
Silver2Falcon (talk) 07:16, 19 December 2008 (UTC)[reply]