Chapter 6

Question 1

is caused by factors that can be identified and managed

Answer 1

Assignable variation

Question 2

testing a sample of output to determine if the process is producing within a preselected range

Answer 2

Statistical Process Control

Question 3

Sampling to accept or reject the incoming material or outgoing finished goods.

Answer 3

Acceptance Sampling

Question 4

a methodology for monitoring quality of manufacturing and service delivery processes to help identify and eliminate unwanted causes of variation

Answer 4

Statistical Process Control (SPC):

Question 5

The essence of statistical process control is to assure that the output of a process is ____ so that future output will be ____(common variation)

Answer 5

Random

Question 6

concerned with monitoring quality while the product or service is being produced

Answer 6

Process control:

Question 7

run charts with control limits added to monitor process output to see if it is random

Answer 7

Control charts:

Question 8

chosen statistically to provide a high probability that points will fall between these limits if the process is in control

Answer 8

Control limits

Question 9

a system governed only by common causes

Answer 9

stable system

Question 10

if no special causes affect the output of the process

Answer 10

in control

Question 11

when special causes are present in the process

Answer 11

Out of control:

Question 12

variation that is inherent in the process itself

Answer 12

Common (or natural) variation:

Question 13

one that is calculated from data that are MEASURED as the degree of conformance to a specification on a continuous scale of measurement

Answer 13

Continuous metric (variable data)

Question 14

one that is calculated from data that are COUNTED

Answer 14

Discrete metric (attribute data)

Question 15

a plot of the means of the samples taken from a process

Used to monitor the central tendency (mean) of a process

Answer 15

X-bar charts:

Question 16

a plot of the range within each sample
The range is the difference between the highest and lowest numbers in each sample
Used to monitor the process dispersion

Answer 16

R-chart:

Question 17

: Control chart used to monitor the percent (or proportion) of defectives in a process
When observations can be placed into two categories
Examples: good or bad, pass or fail, operate or don’t operate

Answer 17

p-Chart

Question 18

Control chart used to monitor the number of defects per unit
Used when not possible to compute population percentages
Use only when the number of occurrences per unit of measure can be counted; non-occurrences cannot be counted

Answer 18

c-Chart:

Question 19

constructed from historical data, the purpose of a ___ is to help distinguish between natural variations and variations due to assignable causes

Answer 19

control charts

Question 20

Range of acceptable values established by engineering design or customer requirements

Answer 20

Specification (or tolerance) limits:

Question 21

the determination of whether the variability inherent in the output of a process that is in control falls within the acceptable range of variability allowed by the design specifications

Answer 21

Process Capability (Cp):