1. What is Scatter Diagram ?
A scatter diagram is used to “examine the relationship between the two, paired, interrelated data types, ” such as “height and weight of a person.”
A scatter diagram provides a means to find whether or not these two data types are interrelated. It is also utilized to determine how closely they are related to identify a problem point that should be controlled or improved.
2. When is it used and what results will be obtained?
The table on next slide shows some examples of scatter diagram’s usage. If, for example, there is a relationship where “an increase in the number of rotations (x) causes an increase in abrasion (y),” there exists “positive correlation.”
If, on the other hand, the existence of a relationship where “an increase in the number of rotations (x) causes a decline in abrasion (y)” indicates that there is “negative correlation.”
Method
Usage
•Used to identify a relationship between two matters.
•Used to identify a relationship between two matters and establish countermeasures based on their cause and effect relation.
Example Usage
1.Relationship between thermal treatment temperature of a steel material and its tensile strengths
2.Relationship between visit made by a salesman and volume of sales
3.Relationship between the number of persons visiting a department store and volume of sales
4 Others [Used during phases to monitor the situation, analyze causes, and review effectiveness of an action.]
Result
•Can identify cause and effect relation.
•Can understand the relationship between two results.
