ASQ: Ch 13 Problem-Solving Tools (P 314 - 352) || with
100% Accurate Solutions.
7 Classic Quality Tools correct answers Scientific tools for analyzing, communicating and
improving process performance. They add efficiency & accuracy to data & decisions.
1. Flowchart
2. Control Charts
3. Histograms
4. Scatter Diagrams
5. Check Sheets
6. Pareto Diagram
7. Cause & Effect Diagram
Flowchart Uses correct answers -Often starting process for process improvement
-Document as-is condition of a process
-Reflect changes to be made to a process (duplication, redundancies, can this be done differently)
-Design an entirely new process
-Fulfill ISO 9001 standard requirement to id and document org process and sequence and
interaction of these processes
Flow charting of a process is done to help analyze the process and confirm that it follows written
instructions. The result of this analysis may lead to the elimination of process steps or
modification of the instructions.
check sheet correct answers Used to gather data on frequency of occurrence
Structured for collecting and analyzing data; generic tool for a wide variety of uses; clusters
indicate the biggest problem areas become visually quickly apparent.
Some examples are A) Recording Charts (tick sheets), B) Checklists (e.g., inspecting products),
C) Measles Sheet (e.g., showing defects or injury location using a schematic of a product or
human).
Data from several check sheets can be organized into a Pareto chart for final analysis
Cause & effect diagram correct answers aka Ishikawa Diagram or Fishbone Diagram
Identifies many possible causes for effect or problem and sorts ideas into useful categories
Breaks problems down into bite-size pieces. Displays possible causes in a graphic manner,
shows how various causes interact. It follows brainstorming rules when generating ideas.
Participants identify problem statement and brainstorm categories then polling to prioritize the
top 3 and then create an action plan.
,Where there could be a long list of potential causes that might contribute to a particular problem.
Causes on one site, effects on the others
4 M's (Manpower, Machinery, Methods & Materials) are categories for manufacturers
4 P's (People, Policies, Procedures, and Plant)
Pareto Chart correct answers Helps you to know where to focus first
80% of the variation in the process is caused by roughly 20% of the variables; he labeled these
variables (vital few) and rest (trivial/many) that have much less overall effect
Control Chart correct answers Graphs used to track how a process changes over time
2 Vital Purposes as data-gathering tool:
Shows when the process is being influenced by special causes, creating an out-of-control
condition, and
It indicates how a process behaves over time
Should examine control charts for nonrandom patterns of data points (can indicate what source
of variation is - i.e., which cause in the C-E diagram is most likely influencing the process so it
can be investigated.)
Charts for variables are most valuable (and expense), may have upper control and lower control
limits.
Advantages:
•Provide a visual display of process performance
•Are statistically sound
•Can plot both attributes and variables
•Can detect special and assignable behavior causes (trends or cycles)
•Indicate time that things are going either good or bad
•Variable charts can provide an on-going measure of process capability
•Can be used to determine if process improvements are effective
Disadvantages:
•Require mathematical calculations in most cases
•Can provide misleading information for a variety of reasons
•Sample frequency can be inappropriate
•Maybe an inappropriate chart selection
•Control limits can be miscalculated
•Can have differing standard interpretations (attribute data)
•Assumed population distribution can be wrong (variable data)
•Very small but sustained sifts can be missed (a need for Cusum charts)
,•Statistical support may be necessary)
Histogram correct answers Provides a graphical picture of frequency distribution of the data
Most commonly used graph for showing frequency distributions, or how often each different
value in a set of data occurs.
Histograms are frequency column graphs that display a static picture of process behavior.
Histograms usually require a minimum of 50 - 100 data points in order to adequately capture the
measurement or process in question. It is characterized by the number of data points that fall
within a given bar or interval (frequency). A stable process is predictable.
Detects distributions that do not demonstrate a typical bell-shaped curve and shows how the
process spread and central tendency (mean/median/mode) relate to process specifications.
In normal bell-shaped distribution, most frequently appeared value (mode) is centered, data
appears equally on either side. Values beyond that are beyond the specification/tolerance limits.
Histogram Comments
•An unstable normal distribution process is often characterized by a histogram that does not
exhibit a bell-shaped curve.
•For a normal distribution, variation inside the bell cure is chance or natural variation. Other
variation is due to special or assignable causes.
•There are many distributions that do not follow the normal curve. Examples include the
Poisson, binomial, exponential, lognormal, rectangular, U-shaped and triangular distributions.
Characteristics of a Normally Distributed Process
•Most of the data are near the centerline, or average
•The centerline divides the curve into two symmetrical halves
•Some of the points approach the minimum and maximum values
•The normal histograms exhibit a bell-shaped distribution
•Very few points are outside the bell-shaped curve.
Scatter diagram correct answers Shows whether or not there is a correlation between 2 variables.
If it appears that values for one of the variables can be predicted based on the value of another
variable, then there is correlation.
Positive correlation correct answers A correlation in the same direction is called a positive
correlation. If one variable increases the other also increases and when one variable decreases the
other also decreases.
Negative correlation correct answers Correlation in the opposite direction is called a negative
correlation. Here if one variable increases the other decreases and vice versa. For example, the
volume of gas will decrease as the pressure increases, or the demand for a particular commodity
increases as the price of such commodity decreases.
, zero correlation correct answers If there is no relationship between the two variables such that
the value of one variable changes and the other variable remains constant
Quality Control Problems solved by the 7 QC TOOLs correct answers can be categorized as
doing 1 of 3 tasks: Problem Identification, Process Improvement & Process Management
7 QC tools identifying problems correct answers Almost all 7 (all but the control chart) of the
QC tools can be utilized during problem identification.
First the Cause and Effect Diagram/Fishbone will help you look at all the potential contributors
to a problem.
Then the Check Sheet is your first line of offense when collecting powerful, actionable data to
support that Cause & Effect Diagram.
After that you can utilize tools like the Pareto Chart to analyze your date and communicate the
top contributors to problems while the Scatter Plot will reveal to you which of your variables
which have the strongest correlations to the measured problem.
QC tools used for Process Improvement correct answers Only 1 of the 7 QC tools can be used for
"process improvement" (e.g., defect reduction, process variation reduction etc.):
The flow chart is a phenomenal tool for communicating the current process and also engineering
the future process. In this way, you can plan and communicate your process improvements
effectively.
QC tools used for Process Management correct answers The Control Chart.
The other 2 tools, the Pareto Chart & Histogram can also be utilized to control and manage an
existing process.
7 new QC tools correct answers developed to organize verbal data diagrammatically. They are
effective for data analysis, process control, and quality; organize concepts, ideas and words
a. Affinity Diagram
2. Interrelationship Diagram
3. Tree Diagram
4. Prioritization Matrix
5. Matrix Diagram or Quality Table
6. Activity Network Diagram
7. Process Decision Program Chart (PDPC)
Integration of 7 new Quality Tools work and the 7 Classical Quality Tools to increase Total
Quality Management correct answers a) Enhanced Capabilities (organize verbal data, generate
