I personally do not pay much attention to most statistics. I think the methods are very faulty and results are often inaccurate due to biases and insufficient sample sizes.
Statistics was showing Hillary Clinton would win by a good margin yet Trump won in 2016.
There are more examples.
How seriously do you take statistics?
Election prediction is unsupervised learning.
The output variable is , here , is a boolean -
Clinton win or Trump win.
Even a rickshawwalla has 50% chance of being right.
The input variables imo can be state polls, previous voting history, orientation of state, demographic specific correlated variables- ( like the logarithm of age of a voter multiplied or divided by his ethnicity, religion, country of origin etc etc, ), social media activity.
Where there is a chance of error is -
a. People lying in an exit poll to appear more agreeable.
b. Human bias with a belligerent personality like Trump
c. Incorrect sampling mech. resulting in selection bias
In other words, even the simplest of null hypotheses assumes there is no interrelationships between input variables.
So any error in input data ( survey etc. ) can lead to violation of assumptions in predictive analysis.
With supercomputers it is easy to do the math, but interpretation of data is very crucial- and that will give you accurate outputs 90 % of the time.
However, my own PERSONAL opinion is -
Trump did the math on his own. He invented a new input variable - its the chemical called
TRUMP-AMPHETAMINE.
He played the sentiment of the public & secretly used analytics to manoeuvre his own campaign in a very creative way, the first time around.
The second time, this chemical was factored in by the opponents.
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