Perceptual and judgment creep

Do we think that a problem persists even when it has become less frequent? Levari et al. show experimentally that when the “signal” a person is searching for becomes rare, the person naturally responds by broadening his or her definition of the signal—and therefore continues to find it even when it is not there.

In a series of experiments, we show that people often respond to decreases in the prevalence of a stimulus by expanding their concept of it. - Prevalence-induced concept change in human judgment

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