UNIVERSITY PARK, Pa. — Tim Prestby, an incoming doctoral student in the Department of Geography, received a National Science Foundation Graduate Research Fellowship to study trust in thematic maps.
Thematic maps are visual tools that show the characteristics of one or more features depicted on a map, such as flood risk or mortality rates. They appear everywhere, from national news broadcasts to social media, and visual mediums such as maps can have a large impact on a broad audience. Reader trust, however, varies, and Prestby intends to identify just what factors influence a map’s trustworthiness.
“Maps are ubiquitous in society, now even more so than usual,” said Prestby, who recently graduated with a master’s degree in geography from Penn State. “There’s a ton of anecdotal evidence that people generally trust maps more than other types of information because they see them as pieces of objective truth. They’re also becoming an increasingly common way to communicate science because a lot of science is inherently spatial, and maps are an intuitive communication medium.”
Prestby’s dissertation, which he will pursue with Anthony Robinson, associate professor of geography at Penn State, will include three separate components. The first will be a thorough review of available literature on how trust has been conceptualized and studied within cartography, geography and related fields like information visualization. He will use the findings to direct the other components of his research.
The second part of his project will examine the psychological factors underlying trust. Specifically, Prestby will look at the potential impact of a map on a reader and how it affects trust. For instance, he will study if showing a flood risk map to an individual who lives in the impacted area would increase or decrease the reader’s trust versus if someone who lived far from the impacted area viewed the same map.
“One of my hypotheses is that if a map shows something that might negatively impact the reader, that person would be less likely to trust the map,” Prestby said. “They will be more likely to critically analyze the map because it is of greater impact to them. Whereas if something isn’t going to affect the reader, the individual is more likely to accept the information at face value.”
He will also study how a map reader’s prior beliefs affect trust. For example, someone who lives on the coast and believes in climate change will be more likely to trust a map showing sea level rise than another person who lives in the same area but holds different views, said Prestby.
The final component of his dissertation will examine how map design characteristics such as color and context, or how a map is framed, affect trust. When it comes to color, cartographers look at congruent and incongruent color schemes and the different ways colors can be interpreted.
“One major way to examine color congruence is through a cultural lens,” said Prestby. “In the United States, map readers generally perceive blue as being cold or potentially sad, whereas red generally communicates heat or feelings like anger. My hypothesis is that if the color scheme is incongruent, then people will trust a map less versus if a color is congruent.”
Context includes where a map appears, whether it be in a scientific journal, magazine or on a social media site, and the details it contains like titles and annotations, explained Prestby. Maps can be highly authored and contain much more writing, or largely open-ended and left to the reader to interpret. All these aspects may affect reader trust, Prestby said.
Prestby’s fellowship will also include an outreach component. The Department of Geography is currently installing a cartographic makerspace, the GeoGraphics Lab, on the University Park campus. Prestby said he would like to use the lab to hold a new workshop series focused on best practices that result from his research to improve spatial scientific communication.
“In order to foster broader trust in science as a whole, we need to make sure that we’re communicating spatial information in really effective ways and also fighting misinformation with spatial data,” he said.
He also said he would like to see the GeoGraphics Lab get involved in some of the mapping classes taught by department faculty to educate and inspire undergraduate students and provide mentorship opportunities with skilled cartographers.
Prestby said he invested a lot of time and effort into the fellowship application and acquired new skills in the process. He credited Robinson, William Head at the University of California Santa Cruz and the rest of Penn State’s Department of Geography faculty for their continuous mentorship and support.
“It’s difficult to describe how good it felt and still feels to receive this fellowship,” he said. “Besides my master’s paper, I haven’t put as much time and effort into a project as I have this application. I’m extremely thankful because the fellowship will completely enrich my experience here at Penn State and allow me to dive into the research that I really want to do.”