Editing Absolute threshold of hearing (section)

==== Staircase (up-down) methods ====
[[Image:Simple Up-Down Method.png|thumb|Series of descending and ascending trials runs and turning points]]

The simple ''1-down-1-up method'' consists of a series of descending and ascending trial runs and turning points (reversals). The stimulus level is increased if the subject does not respond and decreased when a response occurs. Similar to the method of limits, the stimuli are adjusted in predetermined steps. After obtaining from six to eight reversals, the first one is discarded and the threshold is defined as the average of the midpoints of the remaining runs. Experiments have shown that this method provides only 50% accuracy.<ref name="Levitt, 1971"/> To produce more accurate results, this simple method can be further modified by increasing the size of steps in the descending runs, e.g. ''2-down-1-up method'', ''3-down-1-up methods''.<ref name="Gelfand, 1990"/>