TOM3010: Chapter 9: Quality and Statistical Process Control Smartbook

Select all that apply Which are examples of assignable cause variation? Multiple select question. A bottling machine constantly overfills bottles by .2 ounces. A certain number of potatoes in a crop have to be discarded because they are misshapen. A new worker performs a task more slowly than an experienced worker. No two apples on a tree are exactly alike.

A bottling machine constantly overfills bottles by .2 ounces. A new worker performs a task more slowly than an experienced worker.

In the framework for statistical process control which type of variation is investigated and eliminated?

Assignable

Abnormal outcome variation can be attributed to which type of variation in input or environmental variables?

Assignable cause

Which kind of variation is due to a systematic issue?

Assignable cause

Which type of outcome is exemplified by an automobile manufacturer tracking the frequency with which cars are defective?

Binary

Which type of outcome is represented on a p-chart??

Binary

______________-proofing refers to designing a task so that a worker can not complete it in a way that would introduce a defect.

Blank 1: Fool

__________ variables are under the control of the operation or management.

Blank 1: Input

______ variables measure the quality of the outcome of a process

Blank 1: Outcome

A ________ diagram is a graphical way to identify the most important causes of defects. Need help? Review these concept resources.

Blank 1: Pareto

Process _________ is based on comparing the current amount of outcome variation against outcome specifications.

Blank 1: capability

The framework for statistical process control begins with _________ analysis.

Blank 1: capability

The process _________ index tells us how many standard deviations we can move away from the statistical mean before causing a defect.

Blank 1: capability

The C in SPC stands for _____

Blank 1: control

The ________ probability is the likelihood a randomly chosen flow unit does not meet specifications.

Blank 1: defect

The target variation is the largest amount of variation that does not exceed a given _______ probability.

Blank 1: defect

The process capability index tells us how many standard deviations we can move away from the statistical mean before causing a(n) ______.

Blank 1: defect or defects

Environmental variables ______ (do/do not) affect process outcomes.

Blank 1: do

Environmental variables _________ (do/do not) affect process outcomes.

Blank 1: do

A(n) _________ tree shows which combination of events leads to the outcome of a unit without defects.

Blank 1: event

The probability of a unit falling below the LSL and the probability of a unit being above the USL is the same when the _____ of the distribution is in the middle of the tolerance interval.

Blank 1: mean or average

Variation that is due to randomness is referred to as ________ variation or _______ cause variation.

Blank 1: natural Blank 2: common

In a fishbone diagram, a horizontal arrow points at the name of the ________ variable to analyze.

Blank 1: outcome

A _____ process is designed to do well, even under very exceptional conditions.

Blank 1: robust

A __________ process is one where variation in input or environmental variables does not lead to large variation in outcome variables.

Blank 1: robust

A ____________ cause is a change in an environmental or input variable that initiated a defect.

Blank 1: root

The idea of the "5 Whys" is to keep asking "why did this happen" until a ________ cause is found.

Blank 1: root

A beverage bottling company that states that all bottles filled beyond 20.01 ounces are too full. 20.01 ounces is an example of an upper _______ limit.

Blank 1: specification

The output of a process is determined to be defective by comparing outcome variables against a set of __________.

Blank 1: specifications

Capability analysis helps one infer that one process is better than another by measuring the process _________. (Enter one word in the blank.)

Blank 1: spread, variation, variability, or variations

A six-sigma process has six _______ _____________ on either side of the mean and the specification limit.

Blank 1: standard Blank 2: deviations or deviation

The __________ variation is the largest amount of variation in a process that does not exceed a given defect probability.

Blank 1: target

For a p-chart the lower control limit is _________ standard deviations below the center line.

Blank 1: three or 3

Control charts plot data over _____.

Blank 1: time

For a process to be "six sigma," its capability index must be at least ____

Blank 1: two or 2

Which line on a control chart is an average across averages?

Center line

Select all that apply What do the leaves of an event tree represent? Multiple select question. Defects Environmental variables Averages Good outcomes

Defects Good outcomes

For a farmer growing corn, what kind of variable is the weather?

Environmental

Select all that apply A root cause is a change in which kind of variable? (More than one may be correct.) Multiple select question. Environmental Managerial Input Output

Environmental Input

Which statement is true about defect probability?

Even an extremely low probability of defects can cause big problems.

What is represented by the bars in a Pareto diagram?

How often a defect occurs

How will a new method for performing a task that reduces variation affect the process capability index?

Increase it

On which variables in a process does management exert the most control?

Input

For a farmer growing corn, what type of variable is the frequency with which the crops are watered using an irrigation system?

Input variable

Select all that apply Which actions are part of capability analysis? Multiple select question. Identify abnormal outcome variation. Measure outcome variation. Determine likelihood of defects. Compare outcome variation to outcome specifications.

Measure outcome variation. Determine likelihood of defects. Compare outcome variation to outcome specifications.

Select all that apply Which are terms used to describe variations that may appear in output, even when inputs are the same? Multiple select question. Natural variation Input variables Common cause variation Environmental inputs

Natural variation Common cause variation

Which variables are used to measure the quality of process output?

Outcome

Which variables measure the quality of the output of a process?

Outcome

For an investment portfolio, its rate of return would be an example of what kind of variable?

Outcome variable

Select all that apply Which statements are true of p-charts? Multiple select question. Their sample sizes tend to be smaller than those for X-bar charts. P represents the percentage of defective units. They are attribute-based. They track the percentage of defective units over time.

P represents the percentage of defective units. They are attribute-based. They track the percentage of defective units over time.

Which probability do you multiply by 1,000,000 to get ppm?

Probability of a defective unit

Statistical process control is based on what?

Statistical analysis

Select all that apply What is true about environmental variables. Multiple select question. They can be controlled by mangement. They are planned inputs into processes. They are not under the control of management. They have little impact on processes.

They are not under the control of management.

Select all that apply What is true about environmental variables. Multiple select question. They have little impact on processes. They are planned inputs into processes. They are not under the control of management. They can be controlled by mangement.

They are not under the control of management.

Select all that apply Which statements are true of p-charts? Multiple select question. They track the percentage of defective units over time. They are attribute-based. P represents the percentage of defective units. Their sample sizes tend to be smaller than those for X-bar charts.

They track the percentage of defective units over time. They are attribute-based. P represents the percentage of defective units.

True or false: The basic idea of the "Five Whys" is to continually question whether a potential cause is the ROOT cause or merely a symptom of the root cause.

True

Which of the following is true of a robust process?

Variation in input variables does not lead to large amount of variation in outcome variables.

Which should be used to measure the capability of a process?

Variation in outcome variables

Select all that apply Which are examples of input variables in an agricultural process over which management has control? Multiple select question. What type of fertilizer is used How close together seed is planted How often plants are watered How warm the spring will be

What type of fertilizer is used How close together seed is planted How often plants are watered

When is a sample is in line with past process outcomes?

When it falls within the lower and upper control limits.

When is outcome variation is expected to be due to an assignable cause?

When the variation does not fit into the historical pattern of variation

The estimate of the standard deviation of the output unit is based on _blank​_ the output units.

a sample of

X-bar charts can be used to document trends over time and to identify unexpected drifts (e.g., resulting from the wear of a tool) or jumps (e.g., resulting from a new person operating a process step), corresponding to Blank______ causes of variation.

assignable

To calculate the center line of a control chart you compute the _blank​_ of the mean for every period.

average

Low defect rates _blank​_ result in unacceptable outcomes.

can

Ishikawa diagrams are used to visualize the _blank​_ structure of a complex system

causal

An airline tracking defects corresponding to lost luggage, a pharmacy trying to reduce the number of patients who were provided the wrong drugs, or a data entry operation struggling with handwriting recognition all face Blank______ outcomes (a unit is either defective or not).

discrete

Select all that apply Defects are caused by variation in _blank​_ variables. Multiple select question. outcome input environmental

input environmental

The larger the estimated standard deviation, the _blank​_ the quantity UCL-LCL.

larger

The looser the design specifications (e.g. the larger the quantity USL-LSL) the _blank​_ the target variation.

larger

For x-bar charts the _blank​_ of each sample is plotted on the y-axis.

mean

The more steps in a process the _blank​_ likely a defect.

more

Defects are detected based on variation in _blank​_ variables.

outcome

For a p-chart the center line is the average _blank​_.

percentage of defects over all samples

When all steps have to be performed correctly for a unit to be good the probability of a good unit is the _blank​_ of the probability of each step being performed correctly.

product

Defect probability is the likelihood with which a _blank​_ chosen flow unit does not meet specifications.

randomly

Few defects will be produced when the actual process variation is _blank​_ than the target variation.

smaller

The higher the process capability index, the _blank​_ the ppm.

smaller

The larger the sample size, the _blank​_ the estimated standard deviation.

smaller

Assignable cause variation occurs because of a _blank​_ change in input or environmental variables

specific

A six-sigma process has 6 standard deviations on either side of the mean before reaching the _blank​_ limit.

specification

Drag the purpose of a limit to the limit it describes. specification limits<-------> control limits<--------->

specification limits<-------> indicates whether the process meets the requirements of the customer control limits<---------> indicates whether the process is behaving the same way it did in the past

Drag the source of each type of limit to the limit it relates to. specification limits specification limits<-------> control limits<--------->

specification limits<---->business tolerances for when a unit is a defect control limits<------>measurements of past process outcomes

The defect probability is the _blank​_ of the probability that a unit falls below the LSL and the probability that a unit falls above the USL.

sum

A unit is acceptable if it falls _blank​_ the specification limits.

within

To ensure a small number of defects, the control limits should fall _blank​_ the specification limits.

within