How to determine if a value occurs unsually often?

by Sam Porch   Last Updated September 16, 2019 10:19 AM

Example: I have a list of 20,000 dates, such as "X was modified on", or "X was created on". But it's possible one of the dates is being used as a "default" or "null" value.

How would I find the default/null value without already knowing it?

To frame the question another way:

  • How do I determine if one of the dates is occurring unusually often?

  • Or, how do I determine that the quantity of one date is unusual?

It seems like the probability density function should fit in here somewhere. Is there a way to determine the distribution of the dates without knowing beforehand if they're "normal" or "uniform"?

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