Stem-and-leaf plots (also known as stem-and-leaf diagrams) are a valuable combination of a check sheet and a histogram in which the actual data values are recorded so that the raw data is maintained and the distribution of the data is also obvious for all to see. The data are divided into leading digits (‘stems’) and trailing digits (‘leaves’).

Use:  The team would use a stem and leaf diagram as a data collection graphic in much the same way as a frequency distribution or a histogram might be used. The key difference with a stem-and-leaf diagram from a histogram and a frequency distribution is that the raw data is preserved with the stem-and-leaf diagram. In other words, it’s easy to see the raw data as a part of the graphic instead of having to look in a separate area from a histogram to visualize the raw data.

Six Sigma Terminology