Editing Detection theory (section)

=== Sensitivity or discriminability ===

Conceptually, sensitivity refers to how hard or easy it is to detect that a target stimulus is present from background events. For example, in a recognition memory paradigm, having longer to study to-be-remembered words makes it easier to recognize previously seen or heard words. In contrast, having to remember 30 words rather than 5 makes the discrimination harder.  One of the most commonly used statistics for computing sensitivity is the so-called [[sensitivity index]] or ''d'''.  There are also [[non-parametric]] measures, such as the area under the [[Receiver operating characteristic|ROC-curve]].<ref name="Green&Swets"/>