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Seven QC Tools & New Seven QC Tools Cheat Sheet (DRAFT) by [deleted]

This is a draft cheat sheet. It is a work in progress and is not finished yet.

7 QC Tools

Seven QC Tools (Q7)

Statis­tical approach and visual approach are key-po­ints. Graphs are important.

Pareto Chart:** Combin­ation of bar chart and accumu­lation distri­bution chart
Histog­ram:** Graphs of Distri­bution for 1-dime­nsion data
Graph : Bar chart, line chart, pie chart, etc.
Scatter Diagram:** Graphs of Distri­bution for 2-dime­nsion data. To check the relati­onship of two charac­ter­istics
Cause-­and­-Effect Diagram:** Systematic diagram of cause and effect. Similar to mind-m­apping.
Check Sheet:** A list of check points.
Control Chart:** A kind of line chart. X-dime­nsion is time. To check the stability of the movement of data.
Some people say that "­control chart" is one of the "­gra­ph" and stratified sampling is one of the seven QC tools.

7 New QC

New Seven QC Tools (N7)

New seven QC tools are made to analyze non-qu­antity inform­ation (knowl­edge) mainly. Those tools are could be said as reasoning methods.

Affinity Diagram: Grouping of the idea of Brains­torming
Relation Diagram: Diagram of Why-why analysis. It is good to use if cause-­and­-effect contains circul­ation structure
Tree Diagram: Collection of plans and methods system­ati­cally.
Matrix Diagram: A matrix to express the strongness of relati­onship between two things. Basic of QFD (Quality Function Deploy­ment)
Arrow Diagram: Same to PERT
Process Decision Program Chart (PDPC): Same to "Flow chart"
Matrix Data Analysis: Same to Principal Component Analysis

Weakness of Q7 and N7

Most of Q7 are tools for quantity data analysis. But Check-­Sheet and Cause-­and­-Effect Diagram are for knowledge analysis.

Most of N7 are tools of knowledge analysis. But Matrix­-Da­ta-­Ana­lysis is for quantity data analysis. And it is mathem­ati­cally too difficult to study for beginners.

From other viewpoint, Q7 and N7 are not only for Quality Study today because they are introduced as useful tools for various business use. So the name, "­QC", is not suitable.