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Histograms of 50,000 Diamonds


The Sloan Company, a large diamond retailer, compiled histograms of its inventory of 50,000 diamonds before the holidays. The "size" of a diamond is measured in carats.

Two histograms of varying bin width (.2 and .5 carats) were prepared. 1-carat diamonds were recorded in the 1 - 1.5 carat bin, and so on.

Both plots reveal that over half the diamonds are smaller than

carat(s). However, the more detailed plot (smaller bin size) reveals a strong tendency for this diamond retailer to stock diamonds which are conventionally sized (0.5, 1, 1.5 carats etc). Of the 18,600 diamonds larger than one carat, close to

were recorded as either 1, 1.5, or 2 carats, likely because these common sizes are most often sought by consumers.