Wang: Trump is on path to more than 1,237 delegates.

[RandySF]

Today’s update: Trump median 1285 delegates (IQR: 1239-1320). Probability of a pledged majority is 75%.

Despite the usual complaints, primary polls do reasonably well when aggregated. To understand a state, it is far worse to have no polls at all. As the joke goes, “That restaurant’s food is terrible. And such small portions!”

Unfortunately, we have no public polls for the Republican primary in Indiana (update – just in, we have Trump +6%, very close to both of today’s estimates, Trump +7% and Trump +5%). Indiana is pivotal to whether Donald Trump can get to a majority of pledged delegates. You’d think data pundits would rush to fill this void. But that has not been the case.

For any data pundit, the absence of polling has been a serious problem if the question is anywhere close to a tie. At the New York Times, The Upshot has made a demographics-based effort, but I believe that calculation missed Wisconsin (and lacks details). The Great Argental Satan seems to favor Cruz for Indiana in a fairly vague way. He and his staff make extremely weak use of demographics-based analysis, perhaps appropriately so; as far as I am aware, their approach is not strong enough to repair inaccurate polling (for instance, the Michigan Democratic primary). For better performance, there is a need for a method that uses state-level information that is more specific than general demographic composition.

Which brings us to today’s topic. I will show you two independent methods for estimating Trump/Cruz/Kasich support without demographics or polls. This is a long post.

Bottom line: the two methods agree in all important respects. Trump is favored in the remaining Eastern states, including Indiana. Cruz is favored in the remaining states west of the Mississippi (Washington, Oregon, Nebraska, and South Dakota). The only point of disagreement is New Mexico. Both methods indicate that Trump is on a path to more than 1237 pledged delegates.


http://election.princeton.edu/2016/04/22/two-ways-to-estimate-primary-outcomes-without-polls/#more-15154