【How-to】How to find critical value statistics

Critical values for correlation coefficients. Critical Values for the correlation coefficient r. Consult the table for the critical value of v = (n – 2) degrees of freedom, where n = number of paired observations. For example, with n = 28, v = 28 – 2 = 26, and the critical value is 0.374 at a = 0.05 significance level.