2.4.2. Pearson product-moment correlation
The correlation coefficient between students’ self-assessments
of proficiency and actual scores provides information
on the extent to which variation in students’ estimates
of proficiency paralleled variation in their actual scores. Note
that the correlation coefficient is not affected by bias, but
represents covariation between the self-assessments and
actual scores. The statistical significance of findings was
evaluated using an alpha of 0.05. Calculations were performed
using Stata 12.1 (College Station, TX).