Concordant-Discordant Ratio

What is Concordant-Discordant Ratio?

We use concordant-discordant pairs to describe the relationship between pairs of observations. To calculate the concordant-discordant pairs, the data are treated as ordinal. The no. of concordant-discordant pairs is used in calculations for Kendall’s tau, which measures the association between two ordinal variables.

There are a pair of observations- 

The pair is concordant if  (  )

The pair is discordant if (  )