What theory of perception proposes that detection of stimuli depends on a variety of factors including, but not limited to, physical intensity of the stimulus, fatigue of the observer, and expectancy? opponent-process theory signal detection theory multiple perceptual context theory weber's theory?

I believe the answer is: Signal detection theory

Signal detection theory is used to measure researcher's capability to separate information-bearing patterns and random patterns that distract the research from relevant information. Things such as the fatigue level of the observer, could influence how the observe observe things in the experiment, which might caused misinterpretation if the fatigue level is to high.