The frequency illusion (also known as the Baader–Meinhof phenomenon) is a cognitive bias in which a person notices a specific concept, word, or product more frequently after recently becoming aware of it.
[8] Confirmation bias takes effect in the later stages of selective attention, when the individual has already started noticing the specific stimulus.
By focusing on this specific stimulus, the individual notices it more, therefore confirming their suspicions of it occurring more frequently, even though in reality the frequency has not changed.
[4] This phenomenon amplifies frequency illusion since it leads the person to become more aware of recent stimuli and increases the chances of them focusing on it in the near future.
[10] This occurs when stimulus information is not accurately processed or becomes obscured by errors or inconsistencies, leading to reduced variability in how individuals perceive the frequencies of events compared to what is actually observed.
Similar to participants in a conditioning experiment learning reinforcement patterns of certain stimuli, individuals become attentive to differences from an equal distribution in frequency.
The second experiment found that certain factors, like emotions or vivid qualities of items, can lead individuals to overestimate the perception of frequency of occurrences.
This regression effect is more pronounced for smaller sample sizes, resulting in less reliable or accurate estimates of minority statistics and less common occurrences.
[13][14] This cognitive bias can lead individuals to discount rarer causes or events, attributing their perception solely to increased awareness.
[15] Moreover, comparisons to Occam’s razor versus Hickam’s dictum in medicine underscores the need for caution when applying frequency illusions.
This encourages a more nuanced and critical approach to decision-making processes to prevent potential harm or oversight that may arise from relying on oversimplified interpretations of frequency illusions.
However, when the linguists actually transcribed these conversations, the number of times they used the quotative "all" was found to be significantly lower compared to their expectations.
Comparison of statements to linguistic sources such as dictionaries shows that they often don’t match actual language usage patterns.
[19] For instance, during the peak of the COVID-19 pandemic, doctors worldwide would observe discoloration of toes in patients and quickly conclude that it was a sign of COVID-19 due to concurrent timing.
Therefore, increasing salience of specific rare diseases enables healthcare providers to leverage the frequency illusion, enhancing diagnostic accuracy and patient care.
[21] An experimental setup in the lab, simulating an economy and shopping experience for research participants, reveals a tendency in perception biased towards aggregate inflation rates.
This tendency can arise when there are significant gaps in sampling coverage, resulting in inaccurate assessments of changes or trends across a larger area or population.