X-bar and R charts are useful control charts for use with rational subgroups. X-bar measure between-sample variation. R charts measure within-sample variation. All processes vary. The data you collect ...

This paper proposes a heuristic method based on adjusted weighted standard deviation for constructing R chart for skewed process distributions. The asymmetric control limits of the chart are ...

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 ...

This list contains many of the year’s best-selling acts and, track-for-track, it looks like a fairly representative cross-section of 2013 pop. Except it’s not pop—at least, not according to the ...

Drake leads Billboard's 100-position Top R&B/Hip-Hop Artists of the 21st Century retrospective. Below, find a breakdown of the 2000-24 top 10. By Trevor Anderson Drake dominates the competition as the ...