By J. F. Kolacinski,
and B. Payne
Elmira College
Since our last entry the presidential primary season has officially concluded with the primaries in the District of Columbia on June 14th. Clinton and Trump remain the presumptive nominees and little had changed in that regard. Sanders remains an active candidate. The DNC has still not declared Clinton as the nominee, waiting, apparently until the superdelegates officially cast their votes at the Convention. Meanwhile, a “Dump Trump” movement may be taking hold within the Republican Party.
Thus our sole goal for this week is to update our estimate of the probabilities of a general election victory for Clinton and Trump.
Polling Updates:
There is no new state by state polling data for Senator Sanders, so we drop him from our analysis.
The national polling data looks more favorable to Sec. Clinton. As of this yesterday morning she led Mr. Trump 44.9% to 39.1% in the Real Clear Politics Average, a margin of 5.8%. This margin has nearly doubled since our first analysis when Clinton led Trump 44.1% to 41.0%.
In the states, we have updated information in 8 states.
There are now polls available in Oregon, which favors Secretary Clinton and Tennessee which favors Mr. Trump. These polls replace the historical averages.
The RCP Average has shifted in five states; Sec. Clinton sees a slight improvement in Minnesota and Utah, while Mr. Trump saw improvement in Michigan, Virginia and Wisconsin. None of these shifts was enough to change the leader in any of these states; of these five states, Mr. Trump leads only in Utah.
We also corrected an error in the data entered for Missouri.
Probability Estimate:
As we did last week, we estimate our probabilities by simulating a number of state-by-state national elections using the “U.S. Presidential Election Calculator” which can be found here:
< www.maplesoft.com/...>. This application runs on Maple, a professional-grade mathematics program.
Data was taken from www.realclearpolitics.com (retrieved 20 June 2016). The RCP Average was used when one was available. Otherwise the most recent poll was used. Where no polling data was available, we took the average of the last 4 presidential elections.
Poll data was adjusted to eliminate the possibility that a third-party candidate could win the race using the following formula:
% for Candidate A/(% for Candidate A + % for Candidate B).
One thousand simulated elections were run.
The probability of a Clinton victory was 99.5%.
Trump won 0.3% of the time
while 0.2% of the simulations were ties.
The mean electoral result was:
Clinton: 325.9 EV
Trump 212.1 EV
Some Notes on the Map
Last week, using the average simulation to generate the map led to a number of questions, so we switch to our two candidate probability model. In a state, based on the RCP Average, the conditional probability that a voter chooses Clinton assuming he or she chooses either Clinton or Trump is given by:
P(Clinton|Clinton or Trump) = % for Clinton/(% for Clinton + % for Trump)
This is the same formula as above. The key for the map is as follows:
Solidly Democratic (Dark Blue) 100% > P(Clinton|Clinton or Trump) > 55%
Weakly Democratic (Light Blue) 55% > P(Clinton|Clinton or Trump) > 52%
Toss-Up (Gray) 52% > P(Clinton|Clinton or Trump) > 48%
Weakly Republican (Light Red) 52% < P(Trump|Clinton or Trump) < 55%
Solidly Republican (Dark Red) 55% < P(Trump |Clinton or Trump) < 100%