Summary: Engaging in active responses, rather than mere observation, amplifies the influence of previous experiences on future estimations. Through experiments asking participants to estimate the number of dots on a screen, the study revealed a significant effect called serial dependence, where estimates were swayed by prior inputs.
This effect was notably stronger when participants were prompted to respond, highlighting the role of higher cognitive processing in bias formation. These findings underscore the complexity of human perception and offer insights into designing systems to minimize human error by understanding the conditions under which biases in estimation are likely to occur.
Key Facts:
- Serial dependence in estimation tasks is more pronounced when individuals actively engage by responding, showcasing how prior experiences bias future judgments.
- The study conducted two experiments, one with consistent participant responses and another with randomized prompting, to demonstrate the impact of active engagement on bias strength.
- These insights are crucial for developing strategies to present information in ways that mitigate the risk of human error in fields requiring precise estimations.
Source: Osaka Metropolitan University
Does previous experience bias a person in future estimations? Yes, Osaka Metropolitan University researchers in Japan report, but only if the person engages higher processing powers by responding, as opposed to simply observing.
They made their findings through experiments involving participants estimating the number of dots flashed on a screen. Participants either had to input their estimate before making another estimate on a new set of dots or were not prompted to do anything but observe. The researchers found that those asked to respond demonstrated serial dependence.
“What we see or hear is influenced by what we saw or heard before,” said Professor Shogo Makioka at the Graduate School of Sustainable System Sciences, Osaka Metropolitan University.
“The way we are influenced depends on the stimulus and time interval. If we are influenced toward what came before, meaning we are biased toward believing that separate items are more similar, we call that serial dependence.”
The findings were published on January 24, 2024, in Scientific Reports.
In the first experiment in this paper, 35 participants were shown dots for a quarter of a second then prompted to provide their estimated answer for the number before being shown another set of dots. Later, the same participants were shown dots but not prompted to provide an answer, before being shown another set of dots and again prompted to estimate.
In the second experiment, 23 participants were prompted for an answer at random. The researchers found that participants who were prompted to respond were more likely to provide an answer closer to their most recent observation.
“The experiments demonstrated that the influence of serial dependence is stronger immediately after a response is requested,” said co-author Yukihiro Morimoto, a third-year doctoral student at the university.
“This is an important finding when considering how to present information to prevent human error.”
The researchers noted, however, they did not find a correlation between serial dependence and accuracy, likely because the number of dots were random, rather than in intentional groupings or patterns.
According to Professor Makioka, stronger serial dependence following response is due to the higher processing the participant must use to observe and estimate the number of dots, then translate that into an answer.
“We are now investigating whether serial dependence related to numbers also occurs in children and whether it occurs when numbers are presented through sound,” Professor Makioka said.
“Through these studies, we aim to provide clearer guidelines for preventing human error by uncovering, in detail, the ways in which serial dependence arises and how number-related processes work.”
About this basis and neural response research news
Author: Yung-Hsiang Kao
Source: Osaka Metropolitan University
Contact: Yung-Hsiang Kaov – Osaka Metropolitan University
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Response boosts serial dependence in the numerosity estimation task” by Shogo Makioka et al. Scientific Reports
Abstract
Response boosts serial dependence in the numerosity estimation task
Perceptions of current stimuli are sometimes biased toward or away from past perceptions. This phenomenon is called serial dependence. However, the strength of the effect of past responses on serial dependence has not been fully elucidated.
We conducted experiments with a task in which participants estimated the number of dot arrays (numerosity estimation task) and directly compared whether the strength of serial dependence changed in the numerosity estimation task when participants responded or did not respond in the immediately preceding trial.
We also examined whether the strength of serial dependence affected the accuracy of the numerosity estimation. We found that attractive serial dependence was stronger when participants responded in the immediately preceding trial than when they only saw the stimulus.
The results suggest that the information from the previous stimulus must reach the higher-level processes associated with perceptual decisions to influence the estimation of the current stimulus. However, it is possible that the results of this study are specific to tasks in which participants respond with numeric symbols.
The magnitude of the serial dependence effect was not observed to affect numerosity estimation performance, and no evidence was found that serial dependence enhances accuracy in the numerosity estimation task.
