User:Kevin Baas/scratch

$$C(X,Y)$$ $$C(X, Y) = (x(i) – x) * (y(i) – y)$$ $$C(X, Y) = (x(i) – x) * (y(i) – y)$$ $$ C(X, Y) = \frac{ \sum_{i} (x(i) – \bar{x}) * (y(i) – \bar{y}) }{ (\sum_{} (x(i) – \bar{x})^2} $$