Editing Absolute threshold of hearing (section)

== Psychometric function of absolute hearing threshold ==

<!-- Image with unknown copyright status removed: [[Image:Psychometric Function.png|thumb|Sigmoid function]] -->[[Psychometric function]] 'represents the probability of a certain listener's response as a function of the magnitude of the particular sound characteristic being studied'.<ref name="Arlinger, 1991">Arlinger, S. 1991. ''Manual of Practical Audiometry: Volume 2 (Practical Aspects of Audiology)''. Chichester: Whurr Publishers.</ref>

To give an example, this could be the probability curve of the subject detecting a sound being presented as a function of the sound level. When the stimulus is presented to the listener one would expect that the sound would either be audible or inaudible, resulting in a 'doorstep' function. In reality a grey area exists where the listener is uncertain as to whether they have actually heard the sound or not, so their responses are inconsistent, resulting in a [[psychometric function]].

The psychometric function is a [[sigmoid function]] characterised by being 's' shaped in its graphical representation.