Glossary

B

Bernoulli

The Bernoulli distribution takes values of 0 and 1. A Bernoulli variate takes the value of 1 with probability equal to the specified probability parameter.

P

practical significance

A statistical test will answer the question, "Is there a difference between two groups?" but not the follow-up "Is that difference large enough for me to care?" It is up to you to determine whether test results are useful to your situation.

S

Sensitivity

A measure of the usefulness of a classification scheme. Sensitivity is the probability that a "positive" case is correctly classified, and is plotted on the y-axis in an ROC curve. 1-sensitivity is the false negative rate.

Specificity

A measure of the usefulness of a classification scheme. Specificity is the probability that a "negative" case is correctly classified. 1-specificity is the false positive rate, and is plotted on the x-axis in an ROC Curve.