Statistics for Six Sigma Made Easy

11.1. NORMAL DATA

A lathe is machining shafts to a 1.0000" nominal diameter. You carefully measure 100 diameters of these shafts. If you sort the diameters into 0.0005"-wide "bins" and plot this data, you will get a histogram similar to that shown below (Figure 11-2). In this illustration, the ends of the shafts are shown for clarity. This would not be shown in a regular histogram.

In a Histogram, Assume No Values Are on Bin "Edges" When a value appears to be exactly on a bin "edge," convention is to put that value into the higher bin. In the example below, if a shaft were measured to be exactly 1.0000", it would be put into the 1.0000"-to-1.0005" ...