What is a control chart?
•
時間數列
A process is observed by measuring samples.
•
中心線
The center line represents the mean or the
median of the process distribution.
•
管制上下限
The area within the control limits
represents data points due to random
variation.
•
矯正計劃
has to be defined for every control chart.
•
線上的管制圖不需要有規格線