The best histogram maker's will also calculate process capability metrics Cp, Cpk and Pp Ppk. Data points outside of the spec limits represent products or processes that don't meet customer requirements. There can be both an upper spec limit (USL) and a lower spec limit (LSL) or just one of the two. Does your data fit or not? Is it centered?Ĭustomer Requirements are the Specification Limits (Goal Posts)Įxperts refer to these goal posts as specification limits. They are most valuable when they display your customer's requirements as goal posts. Histograms show the spread, or dispersion, of variable data. QI Macros will do the math and draw the graph for you.
Select Histograms & Capability from QI Macros menu.Free Agile Lean Six Sigma Trainer Training.Animated Lean Six Sigma Video Tutorials.Statistical Analysis - Hypothesis Testing.
