Battle for White House 2012 - 2 weeks before electionThe statistical analysis has been performed by using the most recent (2 weeks before election) polling data from realclearpolitics. The dataset can be downloaded here, while Matlab code can be downloaded here. The minimum sample size is around 500 people. The analysis employs an imprecise probability robust Bayesian approach in which robustness is evaluated with respect to the following swing scenarios:
- Best for Romney: in each state the preference of c=2 people among the n polled is changed from Obama to Romney.
- Best for Obama: in each state the preference of c=2 people among the n polled is changed from Romney to Obama.
From the histogram, it can be noticed that there is a high uncertainty. Because of this uncertainty the contribution of the prior on the final result is crucial. In fact, notice that it is enough that in each state the votes of two electors among the n sampled change (they represent less than 0.4% of the total number of the polled voters) from Obama to Romney, that Romney's chance of winning reaches 50%.
The electoral maps of the two cases are reported hereafter for the "Best for Romney" and, respectively, "Best for Obama" case.
The maps show that, based on the polled data, the critical States are Ohio and Iowa. If Romney wins in these two states, his chance of winning goes from 20% to 50%.