Testing the Mercator Effect: Global Map Projections Persuade Differently According to the Emphasis Frames Used to Contextualize Them

Abstract

This study assessed how global map projections affect perceptions of the importance of world regions and beliefs about geopolitical events. We tested whether the Mercator projection, which represents polar regions as being larger than their actual landmass, compared to the Gall-Peters projection, an equal-area map that represents landmass proportionately, alters evaluations of the U.S.’ proposal to purchase Greenland. In a 2 (map projection: Mercator vs. Gall-Peters) × 2 (emphasis frame: economic vs. national security) experiment, we found that people attributed greater importance to Russia after viewing the Mercator projection only when the arguments paired with the map adopted a national security frame. This perception mediated effects of the experimental interaction on attitude toward, support for, and perceived ethics of the purchase.