Six Sigma Foundations and Principles Flashcards
1
Q
What is Six Sigma?
A
A structured and disciplined process designed to consistently deliver perfect products and services.
2
Q
What is the aim of six sigma?
A
To improve the bottom line by finding and eliminating the causes of mistakes and defects in business processes.
3
Q
What is Sigma?
A
A statistical term that refers to the standard deviation of a process about its mean.
4
Q
What does DMAIC stand for?
A
Define, measure, analyse, improve, control.
5
Q
What are Bloom’s levels of cognition?
A
- Remember
- Understand
- Apply
- Analyse
- Evaluate
- Create
6
Q
Processes require inputs and produce outputs. This is generally expressed as?
A
y=f(x)
7
Q
Name 13 key tools used in the Define phase of DMAIC
A
- Is-is not
- Pareto
- Histogram
- Timeline
- Run chart
- Flowchart
- SIPOC diagram
- Stakeholder analysis
- Brainstorm
- Problem definition
- VOC table
- Kano diagram
- Project charter
8
Q
What is the primary methodology used by Six Sigma practitioners?
A
DMAIC
9
Q
How many defects per million opportunities does Six Sigma permit?
A
3.4
10
Q
What amount of shift from the mean is permitted by Six Sigma?
A
1.5 sigma
11
Q
What is the difference between six sigma and lean?
A
Six sigma eliminates process variation, while lean eliminates waste.
12
Q
Which should be used first, lean, or six sigma?
A
Lean first, to remove waste, then six sigma to reduce variability.
Effectiveness before efficiency
13
Q
What does PDCA stand for
A
Plan, Do, Check, Act
14
Q
what does COQ stand for?
A
Cost of Quality
15
Q
What does SIPOC stand for?
A
Supplier
Input
Process
Output
Customer
16
Q
What is the SIPOC tool used for?
A
To describe and understand a process more clearly.
17
Q
In SIPOC, what does “supplier” refer to?
A
The source of inputs.
18
Q
In SIPOC, what does Customer refer to?
A
The recipient of the outputs.
19
Q
What is the “Is-is not” tool used for?
A
Defining the problem by understanding what is not part of the problem.
20
Q
What is the Timeline of events tool used for?
A
To understand the problem through a sequence of events;
one event leads to another.
21
Q
What is the Trend Chart tool used for?
A
To understand process trends from historical event data.
22
Q
What tool would one use to understand positive and negative process trends from historical event data?
A
Trend Chart
23
Q
What is a Run Chart used for?
A
To identify patterns from multiple runs of the process.
non-random trend, oscillation, mixture and clustering
24
Q
What tool would one use to understand process patterns from historical data.
A
A Run Chart
25
What is a Process Flowchart?
A **graphical representation** of the sequence of interrelated activities.
26
What tool would one use to graphically represent a sequence of interrelated activities?
A Process Flowchart
27
What is a Current State Map?
A process map that represents the current state of a process, **including the non-value-adding steps**.
28
What is a GANTT chart used for?
To manage **schedules, resources, costs, and risks**, used in Project Management.
29
What tool would one use to manage schedules, resources, costs and risks during Project Management?
A GANTT chart.
30
What is Stakeholder Analysis?
A tool used to **understand who is influential to a project**, coupled with their level of involvement.
31
What tool would one use to understand who is influential to a project?
Stakeholder Analysis.
32
What is a Data Collection Plan?
A **document** describing the **what, why, where, when, who and how** of data collection.
Prior to collecting data, having a detailed plan can make collection more effective.
33
What tool would one use to plan the collection of data?
A Data Collection Plan.
34
What is Measurement Systems Analysis?
Analysis of the **capability of a measurement system** (tools, methods, people, environment etc).
35
What tool would one use to analyse the capability of a measurement system?
Measurement Systems Analysis.
36
What is a Benchmark?
A **baseline metric** against which the performance of a process is measured.
37
What tool does one use to measure the performance of a process against a current baseline metric?
A Benchmark.
38
What is Process Capability?
The **ability of a process** to meet expected output - SI**P**OC
Often **represented by Cp and Cpk**. The higher the number the better.
39
What tool is used to measure the ability of a process to meet expected output?
Process Capability (Cp, Cpk)
40
What is why-why?
Method of continuing to ask "why" on a problem **symptom** until the **root cause** is reached.
41
What are Hypothesis tests?
**Statistical methods** to test a hypothesis on process improvement.
42
What is statistical sampling?
**Statistically valid** sampling (e.g. power and sample size, acceptance sampling).
43
What is the design of experiments (DOE) tool?
A **statistical tool** for creating **controlled tests**
to evaluate **which factors** control the **value of a parameter** or group of parameters.
44
What is a future value stream map used for?
to visualise a value stream with non-value-added process steps removed.
45
What is the Theory of Constraints tool used for?
Understanding **bottlenecks**.
46
What is the Failure Modes and Effects Analysis (FMEA) tool used for?
to **evaluate potential risk** of failure,
**identify remedial actions** that could eliminate or reduce the risk,
and to **document** the process.
47
What tool should be used to evaluate potential risk and prioritise actions?
FMEA
48
What is Poka-Yoke used for?
to **prevent errors** in processes by "designing in" controls
49
What is a Control Chart (or Process Behavior Chart) used for?
To display process **stability and variability** within control limits **while the work is being done**.
50
What tool would one use to understand the behaviour of a process?
A Process Behaviour, or Control Chart.
51
What is a control plan?
A **table** that defines, in relation to a process
1. **What** to measure
2. **When** to measure
3. **How** to measure
4. How **often** to measure
5. How to **remedy** faults
52
What tool would one use to provide basic information on what is required to manage a process during manufacture or process delivery?
A control plan.
53
What is a process audit?
A tool used to **verify compliance** with a process
54
What tool would one use to verify compliance with a process per the specification?
A process audit.
55
What is Cost of Quality?
A **financial tool** used to report the **difference** between the **actual cost** (with defects) and the **optimal cost** (with no defects).
56
What tool would one use to measure the cost of conformance and nonconformance?
Cost of Quality
57
What are the seven quality tools?
1. Check Sheet
2. Histogram
3. Flowchart
4. Cause and Effect Diagram
5. Pareto Chart
6. Run Chart
7. Scatter Diagram
58
What is another name for Process Control Chart?
Process Behaviour Chart
59
What are the steps in Ishikawa’s process improvement road map?
1. Determine **what is to be measured**
2. Determine **how it will be measured**
3. **Rank** what is to be measured
4. Agree on what is considered **defects and flaws**
5. Expose **latent defects** (look at the process over time)
6. **Observe quality** statistically (use process behavior charting)
7. Distinguish between **"quality of design"** and **"quality of conformance"**
60
What are the steps in the Six Sigma Road Map?
1. Recognise that **variation exists in everything** that we do; **standardise your work**.
2. Identify **what the customer wants** and needs. Reduce variation.
3. Use a problem-solving methodology to **plan improvements**.
4. Follow the **DMAIC** model to deploy the improvement.
5. **Monitor** the process using process behavior charts.
6. **Update** standard operating procedures and lessons learned.
7. **Celebrate** successes.
8. **Start over** for continual improvement.
61
In y=f(x), what does y stand for?
The desired outcome or result of the process.
62
In y=f(x), what does f stand for?
The function or process that will take the inputs and make them into the desired outcome.
63
In y=f(x), what does x stand for?
The inputs necessary to get the outcome (there can be more than one possible x)
64
Name three types of stakeholders.
1. End user
2. Subject Matter Expert
3. Process Owner
65
Why is stakeholder input critical?
1. Stakeholders have the best knowledge base about the process
2. Stakeholders tend to have the best ideas for process improvement
3. Stakeholders are often the most aware of what unintended consequences of process changes
4. Stakeholder buy-in is usually necessary to implement real process improvement.
66
What is a Check Sheet?
A table of pre-categorised potential outcomes used to check the execution of a process.
67
What does FMEA stand for?
Failure Mode and Effects Analysis.
68
Name 13 tools used in the Measure phase of DMAIC
1. Check sheet
2. MSA
3. Process Capability indices
4. Benchmarking
5. COQ/COPQ
6. OEE
7. Process Sigma Level
8. Process audit
9. Financial tools (ROI, NPV, IRR, RONA)
10. Dashboard - RUG monitoring
11. DPPM/DPMO/DPU/RTY metrics
12. Value Stream mapping
13. Equipment /tool correlation study
69
Name 13 tools used in the Analyse phase of DMAIC
1. Why-why/5 why’s
2. Comparative
3. DOE
4. Hypothesis test
5. ANOVA
6. C&E diagram
7. C&E matrix
8. Scatter diagram
9. Stratification
10. Time series analysis
11. Regression analysis
12. Power sample size
13. Multivariate
70
What does DPU stand for?
Defects per unit
71
What does DPMO stand for
Defects per million opportunities
72
What does RTY stand for?
Rolled throughput yield
73
What does COPQ stand for?
Cost of Poor Quality
74
What is the stratification tool used for?
To help dissect data by variables, and interpret the patterns and behaviours in the data set.
75
What is Rolled Throughput yield tool used for?
To assess the combined yield from a series of processes.
76
What is Cycle Time?
The time it takes for a process to be completed from start to end.
77
What is Lead Time?
The time elapsed between order and delivery.
78
What is another way of viewing COPQ ?
The Cost of Nonconformance.
79
What is another way of viewing COQ?
The cost of conformance.
80
What are the 13 steps in performing a Failure Modes and Effects Analysis (FMEA)
1. Review the design/process
2. Brainstorm potential failure modes
3. List potential effects of failures
4. Assign severity rating (S)
5. List potential causes
6. Assign occurrence rating (O)
7. Identify current controls
8. Assign detection rating (D)
9. Calculate Risk Priority Number (RPN)
10. Develop action plan
11. Take action
12. Recalculate the RPN
13. Periodically review and update new risks.
81
What does RPN stand for?
Risk Priority Number
82
How is Risk Priority Number (RPN) calculated?
S x O x D = RPN
Severity x Occurrence x Detection = Risk Priority Number
83
What does RCA stand for?
Root Cause Analysis
84
Why perform Root Cause Analysis (RCA)?
Because there are **apparent causes** and **root causes**, addressing the apparent cause doesn’t eliminate the problem.
85
What is the difference between Value Stream Mapping and Production chess Mapping?
Value Stream Mapping is used more for **lean enterprise projects**, and focuses on **measurement of the flow of material and information** and the **utilisation of resources**.
86
What is Force Field Analysis?
A tool for evaluating **forces for** and **forces against** a problem.
87
What are two categories of Conformance Costs?
1. Appraisal Costs
2. Prevention Costs
88
What are two categories of Non Conformance Costs?
1. Internal failure cost
2. External failure cost
89
What are two classifications of Cost of Quality?
1. Cost of Conformance
2. Cost of Non Conformance
90
Name 7 types of visible costs.
1. Waste
2. Rejects
3. Testing costs
4. Rework
5. Customer returns
6. Inspection costs
7. Recalls
91
Name 18 types of invisible costs.
1. Excessive overtime
2. Pricing or billing errors
3. Premium freight costs
4. Excessive employee turnover
5. Excessive field service expenses
6. Development cost of failed product
7. Planning delays
8. Expediting costs
9. Complaint handling
10. Overdue receivables
11. Late paperwork
12. Lack of follow-up on current programs
13. Excessive systems costs
14. Excessive inventory
15. Time with dissatisfied customers
16. Customer allowances
17. Incorrectly completed sales orders
18. Unused capacity
92
What are appraisal costs?
The costs associated with **measuring and evaluating compliance** of products or services to standards.
93
What are Prevention Costs?
Costs of **measures designed** to **prevent** poor quality **at the source**.
94
What are Internal Failure Costs?
Costs that occur **prior to delivery**.
95
What are external Failure Costs?
Costs that occur **after delivery**.
96
Name 4 financial measures used to perform Cost Benefit Analysis.
1. Return on Investment (ROI)
2. Payback Period
3. Net Present Value (NPV)
4. Internal Rate of Return (IRR)
97
What is Return on Investment (ROI)?
A ratio comparing **net profit** to **investment** expressed as a percentage over a defined period.
98
What is Payback Period?
The time it takes to recoup an investment.
99
What is Net Present Value (NPV)?
The sum of the Present Values (PVs) of income and expenditure over a defined period.
An NPV > 0 is acceptable, the higher the NPV the better.
100
What is Internal Rate of Return (IRR)?
The rate of return used in capital budget g to measure the profitability of investments.
The higher the IRR the better.
