Review 1 Flashcards
1
Q
Name the 3 categories of the Kano model
A
Dissatisfiers, Satisfiers, and Delighters
2
Q
Name 3 strategies for ensuring quality in a process
A
- Quality by Design
- Quality by Process Monitoring and Control
- Quality by Self-Check and Verification
3
Q
Name 3 Levels of Error-Proofing
A
Prevention, Facilitation (mitigate errors), and Detection
4
Q
Which acronym will help you remember the 8 types of waste?
A
TIM WOODS
5
Q
What is the purpose of a Failure Modes and Effects Analysis (FMEA)?
A
To try to anticipate and eliminate ways that a process could fail.
6
Q
When is a Kaizen exercise most appropriate?
A
When the primary drivers of a process’s performance are already known.
7
Q
When is a DMAIC project most appropriate?
A
When an improvement effort is needed and the primary drivers of performance are not yet known
8
Q
What type of project is needed when a process is so broken that it should be redesigned from the ground up?
A
DMADV
9
Q
What is TAKT Rate?
A
the rate of customer demand
10
Q
What is Throughput Rate?
A
the rate at which the process can produce output
11
Q
Name 4 types of the costs of Quality
A
- Appraisal Costs
- Prevention Costs
- Internal Failure Costs (scrap, rework, repair)
- External Failure Costs (loss of customer good will)
12
Q
What is Rolled Throughput Yield (RTY)?
A
the average percentage of yield with no defects
13
Q
What are the 3 key elements of quality?
A
- Customer
- Process
- Employee
14
Q
What is the function of a VOC to CTQ matrix?
A
it helps to translate “critical customer requirements” into CTQs
15
Q
What is a z-score?
A
the number of standard deviations which fit between the specification limits and the mean
16
Q
Name the 3 key elements of Lean Management
A
- Purpose
- Process
- People
17
Q
Lean Focuses on which 3 factors which inhibit performance?
A
- Waste
- Variability
- Inflexibility
18
Q
Name the 5 steps of the 5-S system to reduce waste and optimize productivity via an orderly workplace
A
Sort, Set in Order, Shine, Standardize, Sustain
19
Q
Name 4 strategies to eliminate non-value-add steps in a process
A
Simplify,
Eliminate,
Automate,
Standardize
20
Q
What are the most common causes of defects?
A
- Inappropriate operating procedures
- Excessive variation in operations
- Defective raw material
- Human or Machine error
21
Q
What is Kanban?
A
a scheduling system for Lean and just-in-time production
22
Q
Process Cycle Efficiency (or Value Added Ratio) can be described by which formula?
A
(value add time) / (Total cycle time)
23
Q
What is “overall equipment effectiveness (OEE) and which 3 factors is it based on?
A
OEE is a hierarchy of metrics that provide a KPI as an indicator of success. It’s based on Availability, Performance, and Quality.
24
Q
What is the purpose of the Theory of Constraints?
A
to indicate how to use available resources most effectively
25
What is "The 5-Why Analysis"?
it is a simple root cause analysis tool. Ask "why?" 5 times to each root cause.
26
What is Process Stability?
it defines how consistent are the outputs of a process
27
What is Process Capability?
The ability of a process to meet specifications
28
Which should be established first? Stability or Capability?
Stability should be established first
29
Name 3 types of Location Variations
Bias, Stability, and Linearity
30
Name 2 types of Spread Variations
Repeatability and Reproducability
31
Name two useful tools for Measurement System Analysis
1. Gage Run Chart
| 2. Gage R&R Study
32
In MSA, what does the number of trials and parts generally reflect?
It reflects the criticality of the measurements. More critical equals more trials and parts.
33
How should MSA be set up?
1. The measurement tools should be the same as those used in the production process.
2. Number the parts in advance.
3. Measure the parts in a random order.
34
In MSA, what is the minimum number of trials and appraisers?
At least two trials are required and two appraisers so that both Reproducibility and Repeatibility can be measured.
35
Name a statistical tool that is useful in MSA for Attributes
Attribute Agreement Analysis
36
What does it mean if the Potential Process Capability (Cp) is >= 1 ?
It means that the process is "potentially capable".
37
If the Actual Process Capability is Cpk, then what is the Sigma Level of the process?
Sigma Level = 3 X Cpk
38
What are the 5 Key Steps of the Analyze Phase?
1. List the x's that may impact Y
2. Organize the potential x's
3. Select the most likely Key x's
4. Develop a Data Collection Plan
5. Prove which are the key x's in Y = f(x)
39
In order to help identify the key x's in a process, name 3 graphs for when Y is continuous and X is discrete.
- a histogram
- a box plot
- a dot plot
40
In order to help identify the key x's in a process, name a good Normality Test for when Y is continuous and X is discrete.
the Anderson-Darling test
41
In order to help identify the key x's in a process, name 3 Compare-Means tests for when Y is continuous and X is discrete.
- 1-Sample t test
- 2-Sample t test
- ANOVA
42
Name two Variance tests
1. Chi-Square
| 2. the Bonett method (if data is not normal)
43
Name two tests for equal variance
1. Bartlett's Test
| 2. Levene's test (if data is not normal)
44
If data is not normal, you will typically compare medians instead of means. Name 3 tests used to compare medians.
1. Wilcoxon
2. Mann-Whitney
3. Kruskal-Wallis
45
What if both X and Y are continuous? How will you compare values?
using a Scatter plot or a Fitted Line plot
46
What if both X and Y are DISCRETE? How will you compare values?
using a Pareto Chart
47
How would you test for correlation or independence?
Chi-square contingency tables
48
What is a type-1 error?
Rejecting the NULL hypothesis when it is in fact true
49
What is a type-2 error?
Failure to reject the NULL hypothesis when it it false.
50
What is Beta in error probability?
The probability of a type-2 error happening
51
define the "Power" of a test
Power = 1 - Beta It is the probability of correctly rejecting the null hypothesis when it is false. You want the Power of a test to be as close to 1 as possible.
52
How is the Anderson-Darling Test used?
It is a test for data normality. The null hypothesis is "the Data is Normally Distributed". The alternate is "the data is not normal". If the P-value is greater than 0.05, you fail to reject the null and you conclude that the data is normally distributed.
53
If you perform a test and discover that your data is not normally distributed, what are your options?
Compare medians using non-parametric tests such as:
- Wilcoxon
- Mann-Whitney
- Kruskal-Wallis
54
What would you use to compare the variances of non-normal data?
Levene's Test
55
What are the two key assumptions about the data when you are using ANOVA?
1. The variances are equal (you must confirm this)
| 2. The data is normally distributed (confirm this too)
56
When testing for correlation, what is the null hypothesis?
That there is NO significant correlation
57
What 4 steps will you follow in the course of the Improve phase?
1. Generate Potential solutions to the process problems
2. Evaluate solution options
3. Select the most impactful solutions
4. Pilot and implement your changes
58
Name some tools that you would typically use in the course of the Improve phase
- Process Maps
- FMEA
- Mistake Proofing
- Pilot Testing
59
When is it appropriate to use "Response Surface Methods"?
When it is discovered that your regression function has to account for curvature. A second order or Quadratic model is then required.
60
What are the general goals of the Control Phase?
1. Develop a control plan to monitor, control, and regulate performance
2. Work with process owners to update procedures and develop/implement training plans
3. Help Implement Changes
4. Determine improved process capability and Sigma Level
5. Validate the financial impact of the process improvements
6. Celebrate once the champion signs off
61
What is a P-chart used for?
plots the proportion of defective units
62
What is an NP-chart used for?
plots the number of defective units
63
What is a C-Chart used for?
plots the number of defects
64
What is a U-chart used for?
plots the number of defects per unit
65
What is the Round Robin technique?
a brainstorming strategy where everyone gets a chance to put forth his/her ideas
66
What is the "anti-solution" technique?
a brainstorming strategy that involves ideas on how to make the problem worse rather than solve it. The ideas are then reversed to get the solution to the problem.
67
What is the "6-Hats" technique?
Each team wears one colored hat out of 6 and each color signifies the role he will play in the brainstorming session.
68
What is the "Nominal Group Technique"?
a structured form of brainstorming that results in the generation and prioritization of solutions
69
What is a "Noise Variable"?
an unknown or unaccounted for input variable that is the real reason your Y changed. -- Solution: randomization
70
What is the solution when you have too little data in too short a time period?
Repetitions within each run
71
Name and describe the most powerful of the DOE techniques
Screen Designs -- e.g. Plackett-Burman DOE, Taguchi. These typically have fewer runs but more factors (6-11). Very powerful for uncovering the main factors in a process.
72
Describe DOE Characterization Designs
3-5 factors -- Fractional and Full Factorial DOEs. They typically have more runs but fewer factors and tend to provide more detail.
73
Describe DOE Optimization Designs
<= 3 factors --> Response Surface Method DOEs. Typically have both fewer runs and fewer factors. The Central Composite Design will be the most efficient RSM. These DOEs tend to provide a whole lot of detail.
74
Why are DOEs so powerful?
They provide a way to change many inputs at once to get faster yet reliable results regarding which inputs primarily change Y.
75
What do the R-squared and Adj R-squared tell you?
Whether or not you have too many terms in your equation for the amount of data that you collected.
76
What do you do if R-squared and Adj R-squared are more than roughly 4% apart?
Eliminate the term with the highest P-value from your equation
77
What are residuals?
Our error terms. They will tell us whether our equation works well for all predicted values or just for some of them.
78
What are two good Residual Analyses?
1. Histogram
| 2. Residual vs Fits
79
When analyzing residuals on a histogram, what do we typically want to see?
a normal distribution. But on other plots, we want to see randomness.
80
What is the ultimate Goal of DOE?
To get the most information about the important factors of a process by using the fewest amount of runs
81
Which 4 items must be evaluated as part of the DOE analysis?
1. P-values
2. R-Square
3. +/- 2 * S
4. Residuals
82
In DOE analysis, what is the P-value used for?
it will reveal the significance of various terms in your equation
83
In DOE analysis, what is the R-square used for?
it describes the relationships of inputs to outputs
84
In DOE analysis, why calculate +/- 2 * S ?
it is an indication of the predictability of an equation
85
In DOE analysis, why evaluate residuals?
they are examples of violations of your analysis assumptions
86
What are the general goals of LEAN methodology?
The elimination of waste in order to improve efficiency, flow, and speed.
87
Define Value
Value is what customers need, expect, and are willing to pay for.
88
Define Value Stream
Processes, activities, and resources, including information, used to transform inputs into outputs that are saleable to customers
89
What is a bottleneck or constraint?
The slowest processing step of a value stream
90
What is Just-in-Time Flow?
Items or transactions should be produced, processed, or delivered at the pace of customer demand.
91
What are CTQs?
They are performance characteristics of a process or product or service that are critically important to customers
92
Why calculate the Cost of Poor Quality (CoPQ)?
Those costs are what you can expect to recoup and gain from a successful Lean Six Sigma project.
93
What are the most important goals of Value Stream Mapping?
To get a sense of 1) where value is added, and 2) where waste occurs.
94
What is Lead Time?
Lead Time = Throughput Time. Total time for an item or transaction to move through an entire process.
95
Define Cycle Time
The average time for a unit to be produced or processed.
96
An Attribute Agreement Analysis will try to measure which three things?
1. Percent agreement between appraisers
2. Percent agreement within appraisers
3. Percent agreement with the expert
All agreement should be at least 90% if not higher.
97
Name two different types of descriptive statistics
- - Measures of Central Tendency
| - - Measures of Spread or Variation
98
What are the Four Ws of Stratification in the Measure Phase?
Who, What, Where, and When
99
What is the rule of thumb for when you want to use a histogram?
You need to have at least 45 data points.
100
What factor is most critical to ensure that your experiment has sufficient "Power"?
Sample Size
101
When dealing with a number of possible solutions to implement, which tool can help focus on the best solutions?
a Criteria Selection Matrix
102
Which chart is used to track the stability of the average value of a metric of interest?
Xbar-R Chart
103
Which graph demonstrates the conditions which would be sufficient to enable OCAP for the process?
Xbar Chart
104
Control Charts were developed by Shewhart to track data over time. To detect special cause variation, the control charts use what?
Center line and control limits
105
What types of process variation are the focus of Statistical Process Control?
Common cause and Special Cause variation
106
Special Cause variation falls into which two categories?
Assignable and Pattern
107
What is the technique/tool used to determine if Special Cause errors are occurring within the subgroups of SPC charts?
Range Charts
108
If the production is for higher volume and monitoring and the mean and variability is to be monitored for four machines and the characteristic to be monitored is Variable Data, which SPC chart is best to be selected?
Xbar-R Chart
109
T or F: a fundamental rule is that both Standard Deviation and Variance can be added.
False
110
In addition to a Control Plan, what else is developed at the completion of a LSS project so that those involved know what to do when critical process metrics move out of spec?
a Response Plan
111
The Control Limits width varies if the sample size varies for which type of chart?
P charts
112
Name 3 types of Planned Experiments
- - Fractional Factorial
- - Factorial
- - RSM
113
Which Experimental Design typically has the fewest factors or input variables in it?
RSM
114
T or F: The Lean toolbox includes Design of Experiments
False
115
The method used by Kanban is to require a _____ before anything moves.
Signal
116
Why use a fractional factorial design instead of full factorial?
The reduction in the number of runs will reduce both the time and the cost associated with the experiments.
117
a Full Factorial experiment using a 3 level 3 factor approach has been proposed to test the viability of an extrusion machine experiment. How many treatment combinations will this approach involve?
27
118
When doing hypothesis testing on non-normal data, belts will use what to compare more than two sample proportions to each other?
a Mean-To-Mode analysis
119
It would be more likely than not for a belt conducting a regression analysis to find that the r2 value is smaller than what?
the absolute value of r
120
Which 3 phenomena might contribute to similar distributions having unequal variances?
- - extreme tails
- - outliers
- - multiple modes
121
The relationship between a response variable and one or more independent variables is investigated and modeled using what?
ANOVA
122
How does one assess process proportion as opposed to evaluating a process with respect to a set target?
Process Proportion equals some desired value
123
Which technique is best used to compare a machine 1 average quality characteristic to the same quality characteristic of machine 2?
a 2-sample t-test
124
What has occurred when 2 inputs have a greater impact on a change in output than either of the inputs has by itself?
Interaction
125
To be an effective Lean Six Sigma practitioner, one must understand the difference between .....
Practical and Statistical Significance
126
Why might a belt see multiple modes in a graphical analysis while analyzing data?
The process may have experienced a significant change from one shift to another; there could have been a sizable measurement system error; There might have been a catastrophic failure of some sort.
127
Time is always the metric on the horizontal scale of what kind of chart?
A multi-var chart
128
Which 3 types of variation can impact a process?
Within, Between, and Temporal
129
What could be used to screen variables to analyze their relative impact on the output of concern?
a Multi-Vari chart
130
Some of the sources for different types of error that can be quantified using statistical analysis are:
- - error in sampling
- - bias in sampling
- - error in measurement
131
In a normality test such as Anderson-Darling, what P-values would indicate that the data is normally distributed?
P >= 0.05
132
With Measurement System Analysis, we are concerned with two issues that impact the potential variability of the data. What are they?
Precision and Accuracy
133
What is defined as the difference between the observed and the expected values for a given set of data?
Measurement Bias
134
Appropriate measures means that measurements are what 4 things?
- - Representative
- - Sufficient
- - Contextual
- - Relevant
135
What kind of problem in the measurement system suggests that there is a lack of consistency in the measurement over time?
a stability problem
136
In a good measurement system, the most variation will be with part-to-part measurements. What should you do if the majority of variation is associated with the Gauge R&R, assuming the gauge is technically capable?
Focus on fixing the repeatability and reproducibility of the measurement device
137
What aspects of Measurement Systems Analysis (MSA) studies are applicable when the process that is used to measure does not damage the part?
Nondestructive variable gage R&R and Nested Study
138
When we compare short-term and long-term Capability, what is true of Cp?
Cp is better for the short term
139
Relative to a Design of Experiments, the term Colinear refers to variables being what??
a linear combination of each other
140
Which experimental design is most associated with the fewest number of factors in the design?
Response Surface design
141
Which techniques are typically considered to be part of the Lean toolbox?
- - Poke-Yoke
- - Kaizen
- - 5s the work area
142
If a process has subgroups for variable data and the process runs for a long period of time, then the best pair of SPC charts to use would be....?
and X-bar chart and an R-chart
143
Six Sigma is a business improvement discipline whose fundamental view is based on what?
a performance-oriented approach to the business
144
Much of the Six Sigma methodology is used to identify and remove causes for what?
Process Variation
145
The distance between the Mean of a data set and the Point of Inflection on a Normal curve is called what?
the Standard Deviation
146
When we gather information for the Voice of the Business, we are primarily interested in information concerning what?
the profitability of the business
147
on a typical process map, what shape is used to depict a decision point requiring a Yes or No decision?
a Diamond
148
According to Cost of Poor Quality definitions, what kind of savings is Inventory Reduction?
Hard Savings
149
Customers make their decisions primarily based on 4 things:
1. Features
2. Integrity (of the seller)
3. Delivery
4. Expense
150
Which element of waste best describes "the unnecessary movement of materials and goods"?
Conveyance or Transportation
151
Order Production Cycle is defined as:
The amount of time between the receipt of an order and the receipt of payment
152
What could be defined as "a concise statement of the area of concern and why it is important that the issue be improved"?
Business Justification, aka Management Justification
153
The most important type of FMEA for a product BEFORE going into manufacturing is what?
Design FMEA
154
A major value derived from doing a SIPOC is that it provides insight into which inputs have the greatest affect on what?
on the CTQ outputs
155
Name a valuable tool used during the measure phase that can show material and information flow through out an entire process.
a Value Stream Map
156
Name a tool that is created for every project, based on the team's collective opinions. It is a living document that gets updated whenever a parameter is changed.
an X-Y Diagram
157
What can a belt build in order to help him identify and evaluate risk factors for the subject process?
an FMEA
158
All of the data points that represent the total set of information of interest
the Population
159
Which distribution does not require a logarithmic base for probability calculations?
a Normal Distribution
160
the most frequently occurring value in a distribution of data
the Mode
161
If you wanted to model the data for the number of weaves in a section of carpet fabric, you would use which distribution?
a Poisson distribution
162
A correlation does not explain causation, but what can?
a Regression Analysis with a statistically valid mathematical equation
163
True or False: The Correlation Coefficient is always greater than the Regression Coefficient in a Simple Linear Regression
True
164
The calculation of column total times row total divided by Grand Total yields expected values from what?
a Contingency Table
165
Name some characteristics of a valid mathematical regression
- - the sum of the residuals is zero
- - the residuals when plotted follow a normal distrib.
- - Most standardized residuals fall with +- 2 standard deviations
- - a residual is equal to the difference between the observed and predicted values
166
What is commonly used to investigate and model the relationship between a response variable and one or more independent variables?
Analysis of Variance (ANOVA)
167
If the results from a hypothesis test are located in the "Region of Doubt" area, what can be concluded?
We reject the NULL Hypothesis
168
To be an effective LSS Practitioner, one must understand the difference between .....
Practical and Statistical significance
169
How do we establish a sample size that will allow the proper overlap of distributions?
Calculate 1 minus Beta
170
On which chart will one typically see a pattern from the graphed points such that conclusions can be drawn about the largest family of Variation?
a Multi-Vari Chart
171
What is defined as the difference between the observed and expected values for a given set of data?
Bias
172
the Greek letter sigma is used in mathematics to signify what?
Standard Deviation
173
Those people who have an interest in the output of a process are known as what?
Stakeholders
174
If a design has an alias, what does that imply?
that two factor effects are confused or confounded with each other
175
The theory of constraints focuses on what?
removing constraints and/or bottlenecks to increase throughput
176
All worthwhile management techniques require what?
monitoring, evaluation, review, and continuing improvement
177
name one definition of variance
Variance (V) = sigma squared
178
What is Benchmarking?
it is a system of industrial research which involves comparison of the business typically with a similar business or competitor; usually used as inspiration for improvement
179
When is benchmarking recommended?
when the business suffers some kind of trauma, such as losing a major customer
180
What is QFD?
Quality Function Deployment -- a system for ensuring that customer requirements are aligned with product and process requirements
181
What is Attributes Data?
it indicates the number of times that something occurs or appears in a sample
182
How is Attributes data different from measurements data and which is preferred?
Attributes data only indicates when something occurred, not the degree to which it occured. Whenever possible, Six Sigma professionals obtain measurement data and will occasionally make due with attributes data.
183
In Gauge R & R, what is the discrimination ratio?
it's an estimate of the number of different categories a measurement system can identify.
184
How many different categories are necessary before a measurement system can be subjected to statistical analysis?
8
185
How is a gauge R & R statistic typically expressed?
as a percentage of total process variation or as a percentage of tolerance
186
For both tolerance and process variation what percentages are considered acceptable and unacceptable?
0-10% is acceptable
| more than 30% is unacceptable
187
What will a Linearity analysis do for you in R & R studies?
It judges the possibility that the bias error found in a particular system of measurement will be present throughout the equipment's entire operating range.
188
What is R-squared in a linearity analysis?
It is the coefficient of determination. A value of greater than 70% is acceptable in most cases.
189
What is Metrology?
It is the study of measurement and it is concerned with the quality of measurement systems, the appropriateness of various metrics, and the systems for creating new forms of measurement.
190
What is the goal of applied metrology?
to reduce measurement uncertainly/error
191
what is tolerance in metrology?
the extent to which an instrument will maintain its powers over a long time
192
When is the Central Limit Theorem applied?
when the true distribution of a population is unknown
193
When is the Central Limit Theorem particularly useful?
in control charting and in the calculation of process capability
194
When would it be particularly appropriate to use a Binomial Distribution?
when the units in a population exist in only two states, such as "on" and "off"
195
When would you use a Poisson Distribution?
in situations in which the targeted condition may occur more than once in each unit
196
When is an Exponential distribution used?
used for continuous data obtained by measurement, especially measurements of some event rate.
197
When would you use a Lognormal Distribution?
for continuous data that has a fixed lower boundary (usually zero) and no upper boundary -- often used for reliability data
198
What will typically be used to determine whether any given distribution credibly summarizes the data?
a goodness-of-fit test
199
Name the 4 primary parameters of a statistical distribution.
1. Central Tendency (mean/median)
2. Skewness
3. Standard Deviation
4. Kurtosis
200
define skewness
the distance between the mean and the mode (most commonly occurring value)
201
what will standard deviation basically tell you?
how close to the mean each data point is likely to be
202
what is kurtosis?
the sharpness of the distribution's peak
203
What does it mean if the value of Cp (the the ratio of tolerance to process variation) is less than 1?
It means that your process currently has too much variation (more than what can normally be tolerated) .
204
Name a major difference between statistical control charts and process performance indices.
Process performance indices cannot be used to predict future performance.
205
What does it mean when the process performance index is greater than 1?
It's a good thing. It means that the sample variation is less than the allowable variation.
206
After a process map has been created in the Measure Phase, what will team members typically search for and why?
It will search for areas in the process that seem to require excessive decision-making, which is usually a sign of inefficiency.
207
What are the two objectives of the Analyze Phase?
1. To identify sources and causes of variation in the process
2. To identify non-value-add activities in the process so that they can be eliminated
208
In the Analyze Phase, why would you use an estimation of the confidence interval on mean?
to examine the similarities and differences between the sample means taken during various process conditions
209
What is regression analysis?
it's a system for identifying when a variable is influenced by one or more other variables
210
what are Residuals?
they are the differences between a response's observed value and a regression model's predicted value for that response.
211
What is the most common form of residuals analysis?
a normality test. If the residuals are due strictly to random error, they will follow a perfectly normal distribution in a normality test, with the mean at zero.
212
What is the point of using a multi-vari plot?
it is used to isolate the causes of variation
213
What is process velocity and why do we calculate it?
It is the rate at which value is added during a process phase. The calculation of velocity indicates the degree to which a process responds to customer demands. If there is less work in progress, lead times are shorter and velocity is greater.
214
What is Orthogonality?
the degree to which a design allows all specified parameters to be measured independently of each other.
215
What is "tampering"?
an adjustment that results from making the mistake of treating common cause variation (random) as if it is special cause variation
216
What are Subsidiary Factors (noise factors)?
In a designed experiment, they are factors which contribute to the response and are controlled during the experiment but are not controlled during the normal operation of the process.
217
In the course of an experiment, what is a "casual factor"?
It's a factor that cannot be controlled.
218
What is "Confounding"?
It's a phenomenon in multiple regressions in which multiple factors cannot be estimated outside of the presence of the other(s) due to some correlation or interaction.
219
What is "Operational Confounding"?
This occurs when a metric intended for one variable measures another variable as well, unbeknownst to the researcher.
220
What is "Procedural Confounding"?
This occurs when the researcher, through negligence or error, allows another variable to change with the independent variable.
221
How can confounding typically be minimized or eliminated?
by increasing the type and number of comparisons made during the experiment
222
Why is "resolution" important in experimental design?
It provides information about the types of interactions that can be estimated independently within a particular design.
223
How does one increase resolution in experimental designs?
by performing more and more trials per factor
224
Why are Resolution III designs of very limited use, and what is that use?
In resolution III designs, one or more Main factors may be confounded by an interaction. As a result, they are usually only useful as an initial screening measure.
225
How are resolution IV designs more useful, but still limited, compared to resolution III designs?
In resolution IV designs, main factors are not confounded with 2-factor interactions, although they may be confounded with higher-order interactions.
226
Why settle on a Box-Behnken experimental design?
because it is able to cover the experimental space with fewer points than either full-factorial or a three-level fractional factorial design
227
What is a screening design?
It's an experimental design characterized by a small number of runs and is used at first to identify issues that should receive more attention in future experiments and to eliminate factors from subsequent designs. They still must satisfy resolutions III and IV.
228
What is the purpose of "Normalization" in the course of your experients?
After normalization, identifying the most important factors and interactions should be easier, as should calculating the significance and the numerical accuracy of the regression.
229
When are Contour Plots typically used and for what?
They are typically used in the Improve phase and they are used in RSM to estimate the maximum and minimum responses associated with particular ranges of data.
230
When using a Contour plot, how will you notice that there are interactions occurring between factors?
The lines on the plot will be curved instead of straight and parallel.
231
In the Analyze phase, why do we typically use fractional factorial design?
to identify process performance drivers and sources of variation
232
What are fractional factorial designs used for in the Improve stage?
to estimate the effects of curvature
233
What is a major reason that fractional factorial designs are quicker than full factorial designs?
Since Fractional factorial designs only focus on two factors at a time, they ignore higher-order interactions (interactions between 3 or more factors).
234
The Theory of Constraints emphasizes 3 measurements of system performance. What are they?
Throughput
Inventory (or Investment)
Operating Expenses
235
What is Production Leveling?
a strategy for reducing waste
236
What is a PERT analysis used for?
to estimate the time required for various processes
237
One of the more common Lean tools is Level Loading. What is it?
Its purpose is to regulate and moderate the flow of orders in a particular process.
238
What are some prerequisites that must be covered before level loading can be implemented?
Protocols must be standardized and employees must be trained in multiple areas.
239
What is the intention of level loading strategies?
to eliminate wait time at the beginning of a process
240
Name 3 common methods for controlling processes
1. Statistical Process Control
2. Engineering Process Control
3. Operational Procedures
241
What is Engineering Process Control (EPC)?
it's a mechanical system for automatically adjusting input in response to process variations
242
Engineering Process Control and Operational Procedures are very similar and have the same objective. How are they primarily different?
Operational Procedures are performed by people instead of automated machines.
243
What is the First task of the Control Phase?
standardizing the new methods/improvements
244
What is Total Productive Maintenance (TPM)?
a system for optimizing equipment function so that equipment maintenance never becomes repair or replacement
245
What are the 4 phases of the IDOV methodology?
Identification
Design
Optimization
Validation
246
What is the Law of Completeness?
a system is the synthesis of disparate parts
247
What is the Law of Increasing Ideality?
functions tend to get less complex and more productive
248
What is the Law of Harmonization?
energy is transferred with increasing efficiency
249
What is the Law of Energy Transfer in a sytem?
many inventive problems are based on the flow of energy
250
What is the Law of Uneven Development of Parts?
different aspects of the system will develop at different rates and the overall success of the system will be determined by the least developed aspect.
251
What is the Law of Transition from Macro to Micro?
solutions will decrease in physical size
252
What is the Law of Increasing Substance-Field Involvement?
systems will be viewed as two substances interacting through a field
253
What is the Law of Transition to a Super System?
each solution system will become part of a greater system
254
What is TRIZ?
a theory of inventive problem-solving in which the best solutions resolve a technical or functional contradiction without requiring sacrifice on either side (i.e. improvement of one part of a system should not result in deterioration of another part of a process)
255
Name a quality management tool that is very useful in organizing facts, ideas, and data about a relatively unfamiliar subject.
an affinity diagram
256
When is FTA preferred over FMEA?
When the product is not repairable while in use
257
How does calibration affect precision?
Calibration has a minimal impact on precision
258
How does the portfolio analysis methodology seek to improve on traditional DMAIC approaches?
by enhancing technical processes to prevent design issues
259
Why does one typically replicate an experiment?
it provides a means for estimating the experimental error
260
which quality management technique is considered particularly complex?
a prioritization matrix
261
The measure of the central location for the nominal scale is considered to be what statistic?
the mode
262
List the various statistical levels of measurement in increasing order of desirability
Nominal, Ordinal, Interval, Ratio
263
Team Mechanics typically include things like what?
agendas, times, locations, minutes
264
In CFM, the time per operation is based on what?
the calculation of takt time
265
In the hoshin kanri X-matrix, what are the targeted organizational improvements called?
Aims
266
Which concept is most associated with Taiichi Ohno?
Taiichi Ohno is the main contributor to the Toyoda Production System (TPS)
267
Name a principle of TOC
continuous improvement is essential
268
What is a PEST Analysis?
PEST stands for Political, Economic, Social, and Technological issues that an organization faces
269
Which control chart would be used to monitor defects per unit?
a U-chart
270
In the Drum, Buffer, Rope methodology, what do those items represent?
the drum is the potential process constraint, the inventory ahead of the drum is the buffer, the rope is the feedback mechanism to alert the process to make more inventory
271
What are the 4 steps of the Shewhart Cycle?
Plan, Do, Check, Act
272
Six Sigma strategy development should be performed at what 3 levels?
Business, Operations, and Process
273
What is the clearest indication of effective quality cost efforts?
When management objectives are met
274
Name an advantage and disadvantage of computer based training
Students can choose the pace but it's not always the most appropriate mode of training
275
What is blocking in experimental design?
Blocking is the arrangement of experimental units into groups (blocks) that are similar to one another.
276
What is the benefit of using Blocking in experimental design?
Blocking reduces known but irrelevant sources of variation between units and thus allows greater precision in the estimation of the source of variation under study.
277
What does the Variance Inflation Factor measure?
in Y= f(x), it measures how much the X's are interacting with each other to determine Y.
278
How can you find the Average Outgoing Quality Limit?
The AOQL of a sampling plan is the maximum value on an AOQ curve.
279
What is the most common tool you will use when performing Quality Function Deployment (QFD)?
a House of Quality
280
What is a Latin Square?
a one-fifth fractional factorial experiment
281
Explain the arrangement of categories in a Pareto Chart.
The are typically arranged from highest to lowest left to right but "Other" is usually last.
282
What is a dendogram?
Used in cluster analysis, it looks like a line diagram but it is not. It is a classification tree.
283
Name a few analytical quality tools that involve process or system flow-charting
tree diagrams, PDPC charts, and activity network diagrams
284
What is the object of a DFX approach?
making product controls and functions obvious and anticipating potential human error
285
Which two quality gurus were most closely associated with the terms total quality control and total quality management?
Feigenbaum and Ishikawa
286
What is the major requirement for the effort/impact approach to consensus problem resolution?
the need for reliable, objective data
287
DOE has a tremendous advantage over trial and error because of what?
Even in highly fractional factorial designs, there is replication of the results of one factor vs all others in a balanced design
288
What is the major limitation of both Latin and Graeco-Latin Square (fractional factorial) designs?
They do not allow the analysis of interaction effects. Interactions are confounded with the results of the main effects.
289
What is the F-statistic?
it is the ratio of two sample variances (two chi-square distributions). The assumption is that the samples are drawn from a normal distribution.
290
Name some characteristics of Latin Square design
The focus is on treatments, not interactions. Each treatment appears once per row and column. The design is fully balanced. The number of restrictions = the number of treatments.
291
Two variables are co-linear if they are what?
Totally Correlated
292
What are the experimental assumptions regarding residuals or errors?
they are normally distributed, independent, and homoscedastic
293
What is EVOP?
Evolutionary Operations
294
What is characteristic of Plackett and Burman Geometric designs?
They are always run in multiples of 4 and are screening experiments
295
What is characteristic of Plackett and Burman Non-geometric designs?
They are NOT fractional factorials. They are main-effect designs only
296
What is considered the ideal batch size for a continuous flow operation?
One. The main concept behind continuous flow operation is that material should be moved one piece at a time, at the rate of customer demand.
297
What tools are typically used to perform an analysis of experimental residuals?
Normal probability plots and dot plots are widely used
298
How could you describe experimental error?
The error is due to imperfect uniformity in material and to inherent experimental variability.
299
What can the Box-Cox tool in Minitab do for you?
It can automatically find a suitable transformation that will convert non-normal data into normal data.
300
What is "muda"?
Waste. activity that consumes resources but creates no value.
301
Throughput rate = ?
1 / (cycle time)
302
WIP Inventory = ?
Throughput X Flow time
303
Flow Time = ?
WIP X Cycle Time
304
Total Lead Time = ?
(Number of items in process) / (average completion rate) and also = Flow Time
305
Average Completion Rate = ?
Throughput Rate
306
What is the difference between procedures and work instructions?
Procedures are more high-level - not as detailed as work instructions.
307
Why is a spaghetti diagram useful?
It describes the flow of people, information, and materials.
308
What is the most accurate method for quantifying Repeatability and Reproducibility?
ANOVA
309
Name 3 examples of a discreet distribution
Binomial, Poisson, and hypergeometric distributions
310
Name some examples of continuous distributions
Normal, uniform, exponential, and Weibull
311
What is the formula for Variance?
it = the sum of the squared deviations from the mean divided by the sample size
312
When is the binomial distribution best applied?
when the data is discreet and the sample size is less than 10% of the population size
313
name 3 sampling distributions
Chi-square, t, and F distributions
314
When is it best to apply the hypergeometric distribution?
when the data is discreet and the sample size is a large portion of the population size
315
In comparing attribute data with variable data, which one generally provides more information about a process?
variable data
316
how would control charting differ between short-term and long-term capability analysis?
for short-term, expecting less variability, use X and MR charts. For long-term, where there is more data and more variation, use X-bar and R charts.
317
Process capability analysis tools generally require normally distributed data. What can you do if your data is not normal?
View the data on a histogram and see if it all falls within capability limits. You can also transform the data in order to normalize it, then perform the analysis.
318
Name 4 different transformations that might convert non-normal data into normal data.
- - Log transformation
- - Square root or power
- - Exponential
- - Reciprocal
319
What does normal data look like on a probability plot (such as Anderson-Darling)?
a straight line
320
For attribute data, how do we define capability?
the average proportion or rate of non-conforming product
321
How do we calculate the coefficient of determination?
it is the proportion of explained variation divided by the total variation, when a linear regression is performed.
322
What is the F Test typically used for?
for comparing two population variances
323
What is the Paired t Test used for?
to examine the difference between two sample means
324
What is the Z test used for?
single sample mean, standard deviation of the population is known
325
What is the t Test used for?
single sample mean, standard deviation of the population is unknown
326
What is the Chi (X) squared test used for?
compares observed and expected frequencies of test outcomes
327
Why is MANOVA sometimes preferred over ANOVA?
ANOVAs used across many dependent variables could increase the alpha risk.
328
Name an example of a Chi-Square hypothesis test.
the Kruskal-Wallis test
329
What inference test compares observed and expected frequencies of test outcomes?
Chi Square test
330
Identify the Lean Enterprise technique in which the videotaping of a segment of the operation is helpful.
SUR/SMED
331
Which Japanese technique is most clearly identified with small incremental change?
Kaizen
332
Randomized block experimental design is most like what?
a Latin or Graeco-Latin design
333
When is EVOP typically used?
When a process is already producing satisfactory material but is not operating at its highest efficiency.
334
Which Lean technique is most widely used to make problems visible?
5S
335
The term "level" in experimental design refers to what?
the specific settings of input factors
336
To achieve rapid improvements, which technique might be appropriate?
Kaizen Blitz
337
Which is the best approach to error-proofing activities?
preventative actions
338
Name a special type of randomized complete block design which will remove two sources of variability in the design by blocking in two directions.
Latin Square design
339
What is "Hoshin kanri" or hoshin planning?
It's an execution tool that is used to both organize and deploy strategic plans throughout an organization.
340
Which distribution utilizes a natural log base for probability calculations?
Weibull
341
When do we switch from using Pp and Ppk to Cp and Cpk?
When the process has achieved stability or "statistical control".
342
What does Cpk tell us, in a nutshell?
It tells us what a process is capable of doing in the future, providing that it remains in statistical control.
343
What would you use a Z-test for?
It is a hypothesis test for means -- comparing a population mean to a fixed value when the standard deviation is known.
344
What is a t-test useful for?
It is a hypothesis test for means -- comparing a population mean to a fixed value when the standard deviation is unknown.
345
What is an F-test used for?
it tests if two sample variances are equal
346
What are the 4 most important roles in any typical team?
Member
Leader
Facilitator
Recorder
347
Of all of the resources that upper management provides to a team, which is most important?
Time -- The time to mature, develop, and solve problems
348
Which team role acts as a liaison between the team and upper management?
the Sponsor
349
Who was it that promoted the use of SWOT analysis?
Michael Porter
350
What design process is closely associated with the IDEA process?
Portfolio Architecting
351
Who was the first CEO to understand the need to control variation as a way to significantly improve quality?
Robert Galvin of Motorola
352
What is the best reason for instituting a quality cost system?
To help identify potential improvement areas
353
The aim of portfolio analysis methodology is what?
to enhance technical processes to prevent design issues
354
Give an example of a Natural Work Team
cellular teams
355
Using a balanced scorecard, a learning and growth analysis will attempt to answer what question?
How will we sustain our ability to change and improve?
356
Describe the mindset of a "supportive" management style.
it is a "we'll talk, we'll decide" approach
357
What is typically not part of the calculation for ROA and ROI?
time
358
which business planning process gives consideration to other factors besides just financial ones?
the balanced scorecard
359
who created the problem-solving framework that would eventually become DMAIC?
Mikel Harry
360
the concepts of SMED and SUR would most likely fit into which balanced scorecard category?
internal business process considerations
361
During which phase of the Shewhart cycle would a Pilot test take place?
in the DO phase
362
describe the conflict resolution tactic called "collaboration"
both views are important and an integrated solution is desired
363
How frequently is a Hoshin Kanri matrix reviewed in an organization?
monthly
364
name two types of RSM experimental designs
Central composite and Box Behnken
365
who is most closely associated with the mistake-proofing concept called Poka-Yoke?
Shigeo Shingo
366
Which three elements are contained in a standard work sheet?
materials, workers, and machines
367
who was the originator of the kanban method?
Taichi Ohno
368
Which distribution has a mean equal to the variance?
Poisson
369
What is a major difference between Cp and Cpk?
Cpk corrects for centering. It will always be less than Cp, except in a perfectly centered process where Cp = Cpk
370
In the calculation of Performance Index, which two facts must be known?
the specification limits and the standard deviation
371
What graphical data method can show the value of all individual readings?
a stem and leaf plot
372
name some alternatives to using a histogram to display variable data
box plots and stem and leaf diagrams
373
When is the hypergeometric distribution most often used?
when there are two possible outcomes on each trial but the probability of success on each trial differs because there is sampling without replacement
374
Which is the only distribution with a constant failure rate?
the exponential distribution
375
The probability of occurrence of an event of interest with n trials and f failures follows which distribution?
a binomial distribution
376
How do you convert the average proportion of nonconforming product to DPMO?
by multiplying p-bar by 1 million
377
What do we call a graphical display of the total percentage of results below a certain measurement value?
a cumulative distribution function
378
How do we calculate Rolled Throughput Yield (RTY)?
RTY is the product of the yields of all process steps
379
What is the difference between a statistic and a parameter?
A statistic is a sample value. A parameter is a population value.
380
What is the Weibull scale parameter?
the point at which 63.21% of all values fall below
381
What is the F distribution most commonly used for?
to determine whether or not two sample variances are equal in normal data
382
Little's Law is widely used for what?
In the determination of process flow times
383
What do most goodness of fit calculations tend to have in common?
They use data values structured in cells and a calculated Chi Square test statistic
384
In the Robust Design approach, what is the design output?
Response Factors
385
How do we make decisions based on the F-statistic?
If Fcalc is > than Fcrit, we reject the Null hypothesis
386
How do you determine the degrees of freedom for a Chi-square distribution?
Df = 1 - Sample size
387
Which data type is not compatible with logistic regressions?
continuous data
388
Which table value is usually used to determine confidence intervals for the slope of a line in simple linear regression?
t
389
Which values are used to calculate variance confidence intervals?
Chi square
390
Which values are used to calculate small sample means?
t values
391
Which values are used to calculate large sample means and proportion confidence intervals?
Z table values
392
a Multivariate analysis is applicable for which situations?
There are two or more independent variables and two or more response variables
393
Which test requires no knowledge of population or sample variance (or std deviation)?
the Chi square test
394
When calculating sample size, which parameter is of minimal consideration?
population size
395
What is the best reason to follow up on a successful fix?
to "extend the fix" to other products or services
396
Which two forms of muda (waste) are LEAST likely to result in poor quality?
excess operator motion and waiting
397
1 - Level of Confidence = what?
alpha risk
398
1 - alpha risk = what?
Level of confidence
399
The regression coefficients for LOGISTIC regression models are based on what technique?
Maximum LIkelihood Estimation
400
The regression coefficients for LINEAR regression models are based on what technique?
Least Squares
401
In an Ishikawa Diagram, the box on the far right usually contains what?
The problem statement
402
Which technique is effectively used to complement the cause and effect process?
Brainstorming
403
What is a Fault Tree Analysis?
a graphical method for modeling the reliability of complex systems
404
What do we call it when a false null hypothesis was rejected for the wrong reason?
1 - Beta decision
405
Which Control Phase is appropriate for a DMAIC-turned-DFSS project?
prototype
406
number of defects per unit would closely follow which distribution?
Poisson distribution
407
which control charts frequently have lower control limits of zero?
R and sigma charts
408
When data is less readily available, which control charts become a better option?
X/MR charts and MX-bar-MR charts
409
What are some advantages of using a Median control chart?
- - Easy to use and requires fewer calculations
- - shows process variation
- - shows both the median and the spread
410
What is unique about the X-MR charts?
it's the only control chart which may have specification limits shown
411
Which control charts are especially recommended when information is limited?
moving X-bar, moving range (MR)
412
X-Bar and R charts are used most commonly to separate and compare which two types of variation?
within time and over time variation
413
Nominal and target charts are variations of what?
short run variable charts
414
which type of variation cannot be addressed by control charting and follow-up?
Inherent process variation
415
which type of variation would not be detectable unless it is carefully planned for?
Lot-to-Lot variation
416
What does a training needs analysis focus on?
performance gaps
417
If one needs to know when to investigate a process for causes of variation, which tool is a good choice?
X-bar and R charts
418
Juran provides 3 principle dimensions for measuring the quality of any business process. What are they?
Effectiveness, Efficiency, Adaptability
419
Who's message includes the 4 absolutes of quality management?
Philip Crosby
420
What is the general idea of performing ANOVA?
The equality of sample means can be evaluated by comparing sample variances.
421
Which non-parametric test uses a t-test value?
Levene's Test
422
The Friedman Test, Kruskal-Wallis, and Kendall all require which test value?
Chi-squared (X^2)
423
among the various compare means tests, which is the only one that requires no knowledge of sample or population variance?
Chi Square test
424
Name a graphical analysis method for modeling the reliability of complex systems.
a fault tree analysis (FTA)
425
One-way analysis of variance is most similar in its objectives to what?
a test for equality of two population means
426
an F distribution most closely resembles what?
a chi square distribution
427
what is it called when a false null hypothesis is rejected for the wrong reason?
a 1 - Beta correct decision
428
repeated trials in DOE allows for what?
the determination of experimental error
429
describe Quick Response Manufacturing (QRM)
an integral approach that includes capacity planning, resource utilization, lot sizing, and other concepts to reduce lead times by 80-95%
430
name a technique that can help you maximize the utilization/production of a process bottleneck
drum-buffer-rope technique
431
we can be sure that Placket Burman design runs of 12, 20, 24, 28, and 36 are non-geometric because....?
because geometric design runs are in powers of 2
432
which distribution is most commonly used to model rates, such as defects per car or defects per disk?
Poisson
433
which problem solving technique incorporates PERT and CPM?
an activity network diagram
434
name a couple examples of secondary or consequential metrics
defects per unit and average age of deliverables
435
Eckles suggests that approximately what percent of project time should be spent on the define and measure stages?
50%
436
name a new tool that is used for organizing information, facts, or data into a systematic, logical manner
a tree diagram
437
the elements of project management are:
planning, scheduling, and controlling
438
the main function of a quality cost system is what?
to prioritize resources
439
the typical ratio of new products to successful products is what?
7:1
440
When summing the variances of four components assembled together, we find that:
the assembly would have less variance than that for the sum of all components
441
the best tolerance objective is termed what?
Nominal is best
442
Design for Manufacturability attempts to accomplish what?
Testability and Producibility
