Six Sigma and Beyond: Statistical Process Control, Volume IV
C
Capability
machine
analysis of
forms for, 244 “248
results, 249 “253
setup verification, 250
definition of, 235
Minitab testing
batch files, 392 “393
check, 390
description of, 388
setting up program, 389
SQC loading, 391 “392
typical session, 393 “395
short- term , 235, 326
process
analysis of
data collection sheet, 460
exponential distribution for, 305 “307
non-normal distribution for, 300 “305
sheet for, 461
control charts and specifications, 235
definition of, 231, 235
description of, 104 “105, 107, 128 “129
determining of, 234 “235
illustration of, 318
indices, 253, 257 “261
machine acceptance process, 377 “382
normal distribution, 462
ongoing, 253, 257
overview of, 231 “234
preliminary, 253, 257
process control and, 231 “234
short-run statistical process control, 297
6-sigma, 263 “264
skewed distribution, 463
statistical control and, 234 “235
studies of
control limit method, 236 “243
purpose of, 231
results, 249 “253
trending processes and, 309 “315
Categorical distributions, 50
Cause and effect diagrams, 20 “22
c chart
constructing of, 166 “171
control limits, 167 “168, 171
process center line, 166 “167
process control, 168 “171
sampling plan for, 166
uses of, 166
Centerline, 106
Central limit theorem, 80, 113
Charts, see Control charts; Variable charts
Chi-square distribution, 431 “432
Chi-square goodness-of-fit test
applications of, 85 “86
Cochran's procedure for, 87 “91
description of, 85
exponentiality testing, 90 “91
normality testing, 88 “90
standard type of, 86 “87
Class boundaries, 53
Class frequencies, 53
Class intervals, 53
Class limits, 53
Class marks, 53
Coding, 269
Common variation
control charts for detecting cause of, 106 “107
definition of, 100 “102
description of, 214 “215
trending processes, 308
Constant errors, 330
Contingency tables, 210 “211
Continual improvement
ongoing nature of, 10
reason for, 11
statistical process control for, 5 “6
Continuous probability distribution, 411
Control charts
attribute-type, 125 “126, 458
c chart
constructing of, 166 “171
control limits, 167 “168, 171
process center line, 166 “167
process control, 168 “171
sampling plan for, 166
uses of, 166
centerline of, 106
components of, 105 “106
construction of, 420
contingency tables vs., 210 “211
control limits, 105 “106
cumulative summation, 150 “153
data
attribute-type, 127
collection of, 126 “127
control limits calculated from, 127
description of, 117
summarization of, 51
variable-type, 126
definition of, 99, 129
description of, 4 “5, 103
development of
data, 125 “127
description of, 123 “124
normalization of process, 124
overview of, 124
process capability, 128 “129
process improvement, 129
process variation interpreted for stability and control, 127 “128
forms, 129 “131
funnel experiment
description of, 108
purpose of, 108
rules for, 108 “111
geometric moving average, 205 “207
goals of, 106 “107
history of, 213
hypothesis testing and, 222 “223
level of, 106
log sheet, 459
measurement stability and, 344 ”345
moving-average, 204
multivariate, 210
natural process limits, 106
normal distribution and, relationship between, 113 “114
NP chart
construction of, 162 “165
control limits, 163 “165
description of, 162
overview of, 117
P charts
advantages and disadvantages of, 155
constructing of
control limits, 158 “159, 162
plotting of proportions , 158
process center line, 156 “157, 159
process control analysis, 159 “161
proportion of nonconforming parts , 156
sample plan, 156
standard deviation calculations, 157 “158
variation, 162
vertical scale, 158
process control, 159 “161
PRE-control, 207 “210
preliminary issues regarding, 122 “123
process capability assessed using, 104 “105, 107, 235
process improvements designed from, 107
purpose of
description of, 51, 99, 104
stating of, 124
quality characteristics, 210
red bead experiment, 111 “113
sampling
considerations for, 118 “119
frequency of sample, 119 “121
plan for, 118
rational samples, 118 “119
rational subsamples, 119
short-run, 269, 294 “295
sloping center lines, 148, 150
statistical alternatives, 210 “211
tool wear, 201
trending processes, 307
types of, 125
u chart
constructing of, 172 “175
uses of, 172
variable, 125 “126, 420, 457
variation causes detected using
common, 106 “107
description of, 104
mathematical theorems used, 113 “114
weighted average, 204 “205
Control limits
c chart, 167 “168, 171
description of, 105 “106
NP chart, 163 “165
points beyond, 215 “217
process capability studies using, 236 “243
process data for calculating, 127
R chart, 134 “135
recalculating of, 295
u chart, 174
Xbar chart, 134 “135
Cost of quality, 30
Could cost, 34
c plot point, 289 “290
Cumulative frequency distribution, 56
Cumulative summation control charts, 150 “153
Customer
"insight" of, 6
requirements of, 6
satisfaction of, 9