Provides a static view of the data collected from a process. A histogram displays the basic distribution of the data, including where the central location is, the amount of variation, and whether it is skewed, normal, or symmetric. You can add normal curves (or fit 13 other distributions) to verify whether data are reasonably normal.
|When to Use||Purpose|
|Mid-project||The first rule in data analysis is to always look at a graph of the data before conducting any kind of statistical test. The histogram is a logical choice for any tests in which you are comparing a process output to a standard. Histograms also help you determine whether the data are reasonably normal, a common assumption in many statistical tests.|
|Mid-project||Histograms are good tools for communicating the distribution of a process output at various points in a project to the project stakeholders.|
Numeric Y or X (continuous or discrete)