Download Introduction to Statistical Quality Control

IE 355
Quality & Applied Statistics I
5/7/2017
REVIEW SHEET FOR FINAL
Topics
Introduction to Statistical Quality Control
1. Definition of Quality (p. 6)
2. Cost of Quality
3. Review of Elementary Statistics**
a. Stem & Leaf Plot
b. Histograms
c. Box Plots, Box & Whisker
d. Mean, Mode, Median computations
e. Variance, Standard Deviation, & Range computations
f. Discrete / Continuous Distributions
Simple Comparisons
1. Terms
a. Statistic
b. Mean / Average
c. Variance & Standard Deviation
d. Sampling Distributions
e. Normal Dist
f. Chi-square Dist
g. t-Dist
h. F-Dist
2. Null hypothesis & Alternate hypotheses
a. One-sided
b. Two-sided
3. Type I & Type II Error
a. Power of a Test
b. Significance of a Test
c. P-value
d. Critical Region
e. Confidence Interval
4. Hypothesis Testing
a. Means tests
i. Table
ii. Mean Known
iii. Mean Estimated
iv. Variance / Standard Deviation Known
v. Variance / Standard Deviation Estimated
b. Variance tests
i. Table
ii. Variance / Standard Deviation Known
iii. Variance / Standard Deviation Estimated
5. Assumption Assessment
a. Normal Probability Plots
b. Normality
c. Equal Variance
Methods & Philosophy of SPC
2. Terms
a. Chance (common) Causes
b. Assignable Causes
c. Population / Sample mean, variance, grand mean
d. Statistical Control
e. Specification Limits
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Quality & Applied Statistics I
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‘Magnificent Seven’ tools
a. Histogram / Stem & Leaf
b. Check Sheet
c. Pareto Chart
d. Cause & Effect (Fishbone) Diagram
e. Defect Concentration Diagram
f. Scatter Diagram
g. Control Chart
Statistical Basis for Control Charts
a. Control Limits
b. Rational Subgroups
c. Error Interpretation
a)  Risk
b)  Risk
d. Analysis of Patterns on Control Charts
a) Western Electric Rules
b) Sensitizing Rules
Implementing SPC
a. Elements of a Successful SPC Program (p.185)
Variables Control Charts
2. X-bar & R Charts
a. Control Limits from Standards
b. Control Limits from Point Estimates
c. Process Capability*
a.) PCR Cp
d. Sampling Size & Frequency
a) Operating Characteristic Curves
1. Choice of Sample Size
2. Expected Shift
3.  Risk
b) Average Run Length & Curves
1. In-Control ARL
2. Out-of Control ARL
3. Average Time to Signal
2. X-bar & S Charts
a. Control Limits from Standards
b. Control Limits from Point Estimates
c. Control Limits for Individual Measurements*
* Not covered on Midterm exam, covered on Final
** Assumed from previous coursework, calculation is incidental to the exams.
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IE 355
Quality & Applied Statistics I
5/7/2017
Capability Analysis
1. Terminology
a. Natural Tolerance Limits
b. Specification Limits
c. Fraction Non-Conforming
3. Process Capability
a. PCR Cp
a.) Two-sided
b.) One-sided
c.) Recommended Minimum Values
b. PCR Cpk
c. PCR Cpkm
4. Gage Capability
a. Components of variability
a.) Total
b.) Product
c.) Gage
1. Repeatability
2. Reproducibility
b. Precision to Tolerance Ratio
c. X-bar & R charts for Gage Capability
Attributes Control Charts
1. Terminology
a. Variables (Continuous)
b. Attributes (Discrete)
d. Sampling Distributions
a.) Binomial
b.) Poisson
c.) Ordinate & Cumulative Probability
b. Error Interpretation
a)  Risk
b)  Risk
2. p-Chart
a. Use & Statistics
a.) Mean
b.) Standard Deviation
b. Control Limits
a.) Standards Given
b.) Estimates
c. Charts
a.) Interpretation
b.) Applicable Rules
c.) Trial Limits Process
d. Sample Size
a.) Method 1: n large enough to get at least 1 defective per sample
b.) Method 2: pick n so that 50% chance of detecting a given process shift
c.) Method 3: pick n so that LCL > 0
d.) Variable Sample Size Options
1. Variable Width Control Limits
2. Average Sample Size Control Limits
3. Standardized Control Chart
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Quality & Applied Statistics I
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np-Chart
a. Use & Statistics
a) Mean
b) Standard Deviation
b. Control Limits
a) Standards Given
b) Estimates
c. Charts
a) Interpretation
b) Applicable Rules
c-Chart
a. Use & Statistics
a) Mean
b) Standard Deviation
b. Control Limits
a) Standards Given
b) Estimates
c. Charts
a) Interpretation
b) Applicable Rules
u-Chart
a. Use & Statistics
a) Mean
b) Standard Deviation
b. Control Limits
a) Standards Given
b) Estimates
c. Charts
a) Interpretation
b) Applicable Rules
Individuals Control Charts
1. Use & Abuse
a. When / why to use
2. X & Moving Range Charts
a. Control Limits
a) X Chart Limits
b) Moving Range Limits
1. Calculations
b. Charts
a) Interpretation
b) Applicable Rules
3. EWMA Chart
a. Control Limits
c) Standards Given
d) Estimates
e) Calculations
1. zi
2. z
3. Choice of 
b. Charts
a) Interpretation
b) Applicable Rules
c) Plot / Sketch
4. CUSUM Chart
a. Control Limits
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f) Standards Given
g) Estimates
h) Calculations
1. C+i, N+
2. C-i, N3. Choice of K, H
b.
Charts
a) Interpretation
b) Applicable Rules
c) Plot / Sketch
Acceptance Sampling
1. Considerations
a. Why / why not (w/rt other SPC methods)
b. Lot Formation
c. Random Sampling
2. Single Sampling Plan
a. Process description in terms of parameters
a) N
b) n
c) c
d) PA
e) p
b. OC Curve
a) Probability of Acceptance (PA) computation
b) Description of Ideal vs Practical OC Curves
1. n effect
2. c effect
c) Error Interpretation
1.  Risk
2.  Risk
d) Use of Nomograph
3. MIL STD 105E
a. Terms
a) Normal Inspection (Level II)
b) Reduced Inspection (Level I)
c) Tightened Inspection (Level III)
d) AQL
b. Process description in terms of switching rules
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