chapter  14
24 Pages

Forced and Multiple Choice

The expert in these tasks will need to know about signal detection theory and how to calculate d ′, the receive operator characteristic (ROC), and threshold sigmoids.

In the field of psychophysics, signal detection theory (SDT) is one of the core mathematical frameworks with which to understand and analyze certain types of experimental paradigms. Signal detection theory-as the name implies-is about detecting a signal; more specifically, it is about detecting a potentially noisy signal amid a potentially noisy background. Therefore, the classic SDT experiment involves two conditions, a signal present condition, in which the noisy signal is shown, and a signal absent condition, in which only a noisy background is shown. The noise serves as a tool to make the detection difficult, as otherwise the task would become too trivial.