Variation is the differences between individuals of the same species, caused by genetic and environmental factors. Surveys into variation give data that are continuous, which means to come in a range, ...

2 types of variation and how we distinguish between common and special cause variation, along with how to create a rational subgroup. We also cover the equations and constants for the X-bar and R ...

Forbes contributors publish independent expert analyses and insights. I help people communicate data clearly with graphs. I discussed whether zero needs to be included on all scales in a recent post, ...