Let’s suppose that I have a jar of pennies, which I’ve dumped onto a table, and sorted according to the year in which they were minted. I don’t know when the pennies were put into the jar; it’s possible they were bought from the bank yesterday, and dumped in all at once, or that they were taken out of someone’s pocket at the end of the day for the last five years or more, and the jar filled gradually. I simply don’t know, but it’m curious to find out which among these possibilities, one I haven’t thought of, or some combination thereof, was used to fill the jar.
I’m assuming that there would be some predictable pattern of distribution of pennies from a given year, which when compared to the data collected, would indicate whether they’re representative of the current set of circulating pennies, or not. How much could I find out, simply by looking at the minted dates? How large would the data set have to be to obtain any accuracy?