1. What is Graph ?
A graph is “a graphical representation of data, which allows a person to understand the meaning of these data at a glance.”
Unprocessed data simply represent a list of numbers, and finding certain tendencies or magnitude of situation from these numbers is difficult, sometimes resulting in an interpretational error.
A graph is a effective means to monitor or judge the situation, allowing quick and precise understanding of the current or actual situation.
A graph is a visual and summarized representation of data that need to be quickly and precisely conveyed to others.
2. When is it used and what results will be obtained?
A graph, although it is listed as one of the QC tools, is commonly used in our daily life and is the most familiar means of assessing a situation.
Method
Usage
Changes in a time-sequential order – line graph
Amounts – bar graph, etc.
Ratios – pie graph, band chart, etc.
(The items listed above are representative examples.)
