Concordance correlation coefficient

In statistics, the concordance correlation coefficient measures the agreement between two variables, e.g., to evaluate reproducibility or for inter-rater reliability.

Lawrence Lin has the form of the concordance correlation coefficient ${\displaystyle \rho _{c}}$ as

where ${\displaystyle \mu _{x}}$ and ${\displaystyle \mu _{y}}$ are the means for the two variables and ${\displaystyle \sigma _{x}^{2}}$ and ${\displaystyle \sigma _{y}^{2}}$ are the corresponding variances. ${\displaystyle \rho }$ is the correlation coefficient between the two variables.

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