Behavioral studies in labs on university campuses are overwhelmed with participants who are WEIRD: western, educated, and from industrialized, rich and democratic countries. They are usually college students participating in the studies for class credit.
In an effort to expand these studies to non-WEIRD people too, virtual labs like LabintheWild and Amazon’s Mechanical Turk, open up the study to anyone with access to the internet. These labs give researchers a broader glimpse at the way people think and behave from young to old, around the globe, with diverse cultural beliefs and geographical locations. But, researchers still hesitate to rely too much on these virtual labs because they need a more controlled environment.
Allen School researchers have come up with a tool to allow for more control. The Virtual Chinrest “enables remote, web-based psychophysical research at large scale, by accurately measuring a person’s viewing distance through a 30-second task,” according to the lead author and Allen School Ph.D. student, Qisheng Li.
She said that online studies in psychophysical experiments allow researchers to analyze human perception and performance. Study participants in labs often need to rest their chins in a certain location to control the exercise, making sure each performer is viewing the test from the same place.
“We don’t know how far people in any online environment sit from their computers and we don’t know how big their display of the test is,” said Allen School professor Katharina Reinecke, co-founder of LabintheWild. “The virtual chinrest can monitor both the resolution on the screen and the physical distance from the monitor so researchers have more control over the online studies.”
To first calculate a participant’s display, participants are asked to place a credit card-sized card on the screen and adjust the slider on the screen to fit the credit card. That allows the researchers to calculate the pixel density on the monitor.
To measure the user’s distance from his or her monitor, there is also a blind spot task. Testers are asked to focus on a black square on the screen with their right eye closed, while a red dot repeatedly sweeps from right to left. They must hit the spacebar on their keyboards whenever it appears that the red dot has disappeared. That allows researchers to determine the distance between the center of the black square and the center of the red dot when it disappears from eyesight and understand how far the participant is from the monitor.
In an online test of the Virtual Chinrest on LabintheWild that included 1153 participants, Reinecke’s team was able to replicate and extend the results of previous in-lab studies to prove that the Virtual Chinrest can allow psychophysical studies to be done online, allowing for more diverse participant samples.
Reinecke and her collaborators presented Virtual Chinrest in a recent paper published in the research journal Nature’s Scientific Reports. Additional authors include professor Sung Jun Joo of Pusan National University and professor Jason D. Yeatman of Stanford University.