2016 Democratic Primary
Almost exactly 50% of the votes have been cast in the Democratic Party primary and caucus process. I've been updating a model to predict primary and caucus results all along, and the model has done fairly well. The most recent update, however, was a bit off. That update involved separating states into two groups, southern vs northern, then calculating different sets of likely voting patterns by ethnicity for those two groups, and integrating that with estimates of ethnic distribution ("white, black, hispanic") among Democratic voters by state.
What I did not do in those models was to…