Estimating the relationship between two variables

If X and Y are both ordinal variables with a small number of categories (e.g., for Likert-type scales), Goodman and Kruskal's (1979) gamma is an appropriate statistic. If the data are already in the form of ranks or easily convertible into ranks, one or more rank-correlation coefficients, e.g., Spearman's rho or Kendall's tau, might be ... ................
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