Default options can lead to striking differences in preferences, with significant economic impact. The authors of this Policy Forum use natural and experimental data to examine the impact of simple policy defaults on the decision to become an organ donor, finding large effects that significantly increase donation rates.
Johnson, E. J., & Goldstein, D. (2003). Do defaults save lives?. Science, 302, 1338-1339.
DOI: 10.1126/science.1091721