: Research from the University of Miami notes specific psychological data points, such as 13% of the US population being affected by phobias. Labor Acknowledgement - Solid Ground
: Seminal papers like "The Neglected 95%: Why American Psychology Needs to Become Less American" by Jeffrey Arnett argue that US-centric research (which often focuses on the "US" experience) fails to represent the broader human population. 13. Us
: The design features 13 arrows, 13 olive leaves, and 13 letters in the motto E Pluribus Unum . Official explanations from the National Archives and Wikipedia note these represent the "solid compact" of the several states. : Research from the University of Miami notes
: Legal research often examines the 13th Amendment , which solidified the end of slavery in the US, as a "solid ground" for modern civil rights analysis. Psychology and Research Contexts
: Modern social studies curricula, such as those in Louisiana , use "13" as a primary framework for teaching the founding principles, including economic terms like free enterprise and private property. Psychology and Research Contexts