"A problem with much statistical analysis is ignoring the fact that humans, umm, react to things around them. (Social science jargon for this is reflexivity). I know this seems so simple, but it’s amazing how much predictive analytics don’t factor this in.",
https://medium.com/message/learning-from-natesilver538s-omg-...
Are humans deterministic machines, or do they impose their own freewill on to the environment? Predictions based on statistical analysis probably can't account for freewill.
Statistics can account for free will just as well as they account for other complex factors, which is poorly, with no ability to say what will happen in any particular case. There's no need to get metaphysical.