Six Sigma Tool Navigator: The Master Guide for Teams

2017-07-07 02:10:07

AKA

N/A

Classification

Analyzing/Trending (AT)

Tool description

A run chart is a simple monitoring tool that indicates a trend of change or process over a specified time. Observed data is plotted in sequence and connected by a line to show runs. Run charts can be used for monitoring any variation from an average, the increasing/decreasing trends in performance or defects, or any other change in normal data patterns.

Typical application

To observe process variation over time.

To plot data for the purpose of identifying any changes or trends in the average.

To receive an early warning of a potential problem due to an observed pattern of plotted data that shows an undesirable trend or variation.

Problem-solving phase

→	Select and define problem or opportunity
→	Identify and analyze causes or potential change
	Develop and plan possible solutions or change
	Implement and evaluate solution or change
→	Measure and report solution or change results
	Recognize and reward team efforts

Typically used by

1	Research/statistics
	Creativity/innovation
	Engineering
3	Project management
4	Manufacturing
	Marketing/sales
	Administration/documentation
	Servicing/support
	Customer/quality metrics
2	Change management

links to other tools

before

Checksheet

Observation

Data Collection Strategy

Polygon

Surveying

after

Problem Specification

Process Analysis

Problem Analysis

Potential Problem Analysis (PPA)

Monthly Assessment Schedule

Notes and key points

A run chart is simply a chart showing runs and trends. It is not as powerful as a control chart that determines if a process is in or out of control on the basis of calculated upper and lower control limits.

A rough indication of a potential problem may be the consecutive increase or decrease of six or more points in row (a run).

Another indication of a process change may be the consecutive run of nine or more points on one side of a plotted average () center line of the run chart.

Plot at least twelve data points to increase the probability of observing a meaningful pattern.

Step-by-step procedure

STEP 1 If possible, collect historical data of the process to be observed. This will provide a baseline, or an average, for the run chart to be constructed. See example "Tools for Teams" Training Participant Attendance.

STEP 2 Develop a run chart showing time horizontally and a discrete or continuous interval scale vertically.

STEP 3 Plot the observations (measurements) in sequential order as they are collected. Connect data points with straight lines.

STEP 4 As the run chart is developed, check for trends, variations, or indications of potential problems.

STEP 5 Date and save run charts for formulating a problem specification.