US support for gay marriage, graphed

The chart is based on a hierarchical model of polling data by Jeff Lax and Justin Philips. They used the glmer function in R to aggregate poll data from various sources and create an “opinion estimate” for each state in three periods: 1994-1996, 2003-4 and 2009-9. It shows clearly how support for gay marriage has been steadily increasing everywhere (with the notable recent exception of Utah), but is generally increasing fastest in those states where some… 

The chart is based on a hierarchical model of polling data by Jeff Lax and Justin Philips. They used the glmer function in R to aggregate poll data from various sources and create an “opinion estimate” for each state in three periods: 1994-1996, 2003-4 and 2009-9. It shows clearly how support for gay marriage has been steadily increasing everywhere (with the notable recent exception of Utah), but is generally increasing fastest in those states where some same-sex rights have already been conferred. Andrew Gelman provides further detailed commentary of this chart in an op-ed for the political website NewMajority.com. It’s nice to see such in-depth statistical analysis and graphics from R having an impact on political discourse.