Reducing the low prevalence effect: Does similarity search translate to binary decisions?

Area of Science:

• Cognitive Psychology
• Visual Perception
• Human Factors

Background:

• The low prevalence effect (LPE) is a common phenomenon in visual search where rare targets are frequently missed.
• Existing cognitive interventions often fail to mitigate the LPE.
• Similarity search has shown promise in eliminating the LPE in controlled settings.

Purpose of the Study:

• To investigate if the benefits of similarity search extend to binary decision tasks.
• To determine if similarity search can attenuate the LPE with more naturalistic stimuli.
• To explore the limitations of applying similarity search in real-world scenarios.

Main Methods:

• Participants performed visual search tasks with manipulated target prevalence, using T-shapes among near-T distractors.
• Two conditions were tested: similarity search only, and similarity search combined with a binary decision (target present/absent).
• A second experiment used naturalistic road video stimuli, requiring participants to identify hazards and make a binary response.

Main Results:

• Similarity search partially attenuated the LPE in some circumstances.
• A significant LPE was observed for the binary decision task in both experiments.
• Participants were less accurate in classifying targets as present during low prevalence conditions.

Conclusions:

• While similarity search can reduce the LPE, its effectiveness is limited when binary decisions are involved.
• The LPE remains a challenge in visual search tasks requiring yes/no judgments, even with naturalistic stimuli.
• The application of similarity search in real-world settings may be constrained by the necessity of binary decision-making.