What is a run chart?

A run chart is defined as a graph that displays data points over time, which helps in identifying trends, shifts, or any patterns in the data. By plotting data points in chronological order, a run chart visually represents how a particular variable changes over time, making it a valuable tool for tracking performance or outcomes. This ability to observe changes and trends is essential in quality improvement efforts, as it allows teams to see the effects of changes implemented in a process, assess variability, and monitor improvements over time.

In contrast, the other options do not accurately describe a run chart. While a graph showing the distribution of data points in a sample relates more to statistics and probability (like histograms), and a comparison of two different datasets suggests the use of other graphs such as bar charts or scatter plots, a run chart's sole focus is on the temporal aspect. Additionally, while seasonal changes might be relevant for certain types of data, this concept is more appropriately represented in a time series analysis or specific types of run charts focused on seasonal trends rather than a general definition of a run chart itself.