1. QUALITY CONTROL TOOLS FOR PROCESS IMPROVEMENT
Chapter 12-Supplement
QUALITY CONTROL TOOLS FOR PROCESS IMPROVEMENT
McGraw-Hill/Irwin
© 2003 The McGraw-Hill Companies, Inc., All Rights Reserved.

2. LEARNING OBJECTIVES
Introduce the basic tools for analyzing processes and quality.
Describe acceptance sampling and when it can be used to control
quality in services.
Introduce statistical process control and describes how and when
it can be used to analyze service processes.
Define the types of sampling errors that can occur when statistical
sampling is used.
Distinguish between the statistical analysis of attributes and variables.

3. THE SEVEN BASIC QUALITY TOOLS
Process Flow Diagrams
Checksheets
Histograms/Bar Charts
Pareto Charts
Scatterplots
Run Charts
Cause-and-Effect Diagrams

4. Exhibit 12S.1
PROCESS FLOW DIAGRAM: DRYCLEANING SERVICE

5. Exhibit 12S.3
CHECKSHEET

6. Exhibit 12S.4
EXAMPLE OF A BAR CHART

7. Exhibit 12S.5
EXAMPLE OF A HISTOGRAM

8. Exhibit 12S.6
EXAMPLE OF A PARETO CHART

9. Exhibit 12S.8
EXAMPLE OF A SCATTERPLOT

10. Exhibit 12S.9
EXAMPLE OF A RUN CHART

11. Exhibit 12S.10
EXAMPLE OF A CAUSE-AND-EFFECT DIAGRAM

12. Exhibit 12S.11
THE EIGHT STEP QUALITY IMPROVEMENT PROCESS

13. TWO BASIC MODELS FOR STATISTICAL QUALITY CONTROL
Acceptance Sampling: This involves testing samples after the goods or services have been produced.
Statistical Process Control: This involves testing samples of goods or services as they are being produced.

14. Exhibit 12S.12
THE RELATIONSHIP BETWEEN POPULATION QUALITY AND SAMPLE FINDINGS
What the Population Quality Actually Is
Good
Bad
Good Lot Accepted: No Error
Bad Lot Accepted: Type II Error or 
Good
What the Sample Finding Is
Good Lot Rejected: Type II Error or 
Bad Lot Rejected: No Error
Bad

15. Exhibit 12S.13
OPERATING CHARACTERISTIC CURVE

16. Exhibit 12S.14
THE NORMAL DISTRIBUTION

17. PROCESS CAPABILITY
Collect data on the process while the process is operating without known causes of variation.
Compare the customer’s requirements to the inherent variation of the process.

18. Exhibit 12S.16
CAPABILITY STUDY

19. Exhibit 12S.17
SIX-SIGMA QUALITY

20. Exhibit 12S.20
CHANGES IN MEAN AND DISPERSION OF SAMPLE MEAN DISTRIBUTIONS

21. KEY TERMS
Acceptance Sampling
Capability
Central Limit Theorem
Operating Characteristic Curve
Statistical Process Control
Type I Error
Type II Error
Variables