# Linear vs non-linear Correlation

How do i check that two random variables satisfy the requirements for computing correlation via Pearson or Spearman? If the data is non-linear/ non-Monotonic, are there other tests i could use to compute a correlation coefficient?

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The link in your answer is not hyperlinking correctly. Please try putting triangle braces (< >) around it or putting space between the parenthesis and link. –  Evan Teitelman Feb 23 '13 at 12:33