1. Run chart 1
Run chart
A run chart, also known as a run-sequence
plot is a graph that displays observed data in
a time sequence. Often, the data displayed
represent some aspect of the output or
performance of a manufacturing or other
business process.
Overview
Run sequence plots[1] are an easy way to
graphically summarize an univariate data
set. A common assumption of univariate
data sets is that they behave like:[2]
A simple run chart showing data collected over time. The median of the observed
• random drawings;
data (73) is also shown on the chart.
• from a fixed distribution;
• with a common location; and
• with a common scale.
With run sequence plots, shifts in location and scale are typically quite evident. Also, outliers can easily be detected.
Examples could include measurements of
the fill level of bottles filled at a bottling
plant or the water temperature of a
dishwashing machine each time it is run.
Time is generally represented on the
horizontal (x) axis and the property under
observation on the vertical (y) axis. Often,
some measure of central tendency (mean or
median) of the data is indicated by a
horizontal reference line.
Run charts are analyzed to find anomalies in
data that suggest shifts in a process over
time or special factors that may be
influencing the variability of a process. Run chart of eight random walks in one dimension starting at 0. The plot shows the
current position on the line (vertical axis) versus the time steps (horizontal axis).
Typical factors considered include unusually
long "runs" of data points above or below
the average line, the total number of such runs in the data set, and unusually long series of consecutive increases or
decreases.[1]
Run charts are similar in some regards to the control charts used in statistical process control, but do not show the
control limits of the process. They are therefore simpler to produce, but do not allow for the full range of analytic
techniques supported by control charts.
2. Run chart 2
References
This article incorporates public domain material from websites or documents [3] of the National Institute of
Standards and Technology.
[1] Chambers, John; William Cleveland, Beat Kleiner, nd Paul Tukey (1983). Graphical Methods for Data Analysis. Duxbury.
ISBN 053498052X.
[2] NIST/SEMATECH (2003). "Run-Sequence Plot" (http:/ / www. itl. nist. gov/ div898/ handbook/ eda/ section3/ runseqpl. htm) In:
e-Handbook of Statistical Methods 6/01/2003 (Date created).
[3] http:/ / www. nist. gov
Further reading
• Pyzdek, Thomas (2003). Quality Engineering Handbook (Second Edition ed.). New York: CRC.
ISBN 0-8247-4614-7.
External links
• Run-Sequence Plot (http://www.itl.nist.gov/div898/handbook/eda/section3/eda33p.htm)
3. Article Sources and Contributors 3
Article Sources and Contributors
Run chart Source: http://en.wikipedia.org/w/index.php?oldid=402132258 Contributors: Btyner, Craigkbryant, DanielPenfield, David Haslam, Davidelit, G716, Hooperbloob, Linas, Mdd,
Melcombe, Michael Hardy, Nekohakase, Paul August, Pmc, Qwfp, 10 anonymous edits
Image Sources, Licenses and Contributors
Image:SimpleRunChart.jpg Source: http://en.wikipedia.org/w/index.php?title=File:SimpleRunChart.jpg License: Public Domain Contributors: Mdd
Image:Random Walk example.png Source: http://en.wikipedia.org/w/index.php?title=File:Random_Walk_example.png License: GNU Free Documentation License Contributors: ChongDae,
Darapti, Mdd, Ordoon, Toobaz, 1 anonymous edits
Image:PD-icon.svg Source: http://en.wikipedia.org/w/index.php?title=File:PD-icon.svg License: Public Domain Contributors: User:Duesentrieb, User:Rfl
License
Creative Commons Attribution-Share Alike 3.0 Unported
http:/ / creativecommons. org/ licenses/ by-sa/ 3. 0/