I received feedback from some friends to suggest that this is not applicable to large datasets - i.e. big data. I play with my own quantified self data sets of 100,000+ lines from time to time. (think minutised data at 1440 minutes a day for a year and counting). Can you discuss this more (maybe in the next open thread?)
It shouldn't be too challenging to apply Nelson rules to 100k lines, but the point of statistical process control is continuous monitoring--if you weigh yourself every day, you would look at the two-week trend every day, for example. Writing a script that checks if any of these rules are violated and emails you the graph if that's true seems simple and potentially useful.
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