I-MR Chart Maker

Here you can easily create an I-MR Chart online! Simply copy your data into the table and select the measurements.

The I-MR Chart will then be created for you online.

Create an I-MR Chart online

In Statistical Process Control (SPC), an I-MR Chart, also known as an Individuals and Moving Range Chart, is a type of control chart used to monitor the stability and variation of a process when individual measurements are taken. The chart consists of two components: the I Chart (Individuals Chart) and the MR Chart (Moving Range Chart).

I-Chart (Individuals Chart):

• The I-Chart displays individual data points over time, with each point representing a single measurement or observation from the process being monitored.
• A center line is drawn on the chart to represent the average or mean of all the individual data points.
• Upper and lower control limits are also plotted on the chart, typically set at a certain number of standard deviations (usually three) from the center line.
• The I-Chart helps monitor the variation of individual data points and detect any patterns or trends that may indicate process instability.

MR Chart (Moving Range Chart):

• The MR Chart displays the moving ranges between consecutive data points on the I-Chart.
• Moving range is calculated by taking the absolute difference between consecutive data points: MR = |X_i - X_(i-1)|, where X_i is the current data point and X_(i-1) is the previous data point.
• A center line is drawn on the MR Chart to represent the average or mean of all the moving ranges.
• Upper and lower control limits are also plotted on the MR Chart, typically based on statistical methods appropriate for moving ranges.
• The MR Chart helps monitor the variation between consecutive data points and assess the stability of the process.

Interpretation of the I-MR Chart involves analyzing both the I-Chart and the MR Chart:

• In the I-Chart, if data points fall within the control limits and show random variation around the center line, the process is considered to be in control.
• In the MR Chart, if moving ranges fall within the control limits and show random variation around the center line, it suggests that the process is stable.

The I-MR Chart is commonly used in industries such as manufacturing, healthcare, and finance to monitor and improve processes, identify potential issues early, and make data-driven decisions for process improvement.