DTIC ADA373267: Optimization of Fit for Mass Customized Apparel Ordering Using Fit Preference and Self Measurement.

287 Pages·14.7 MB·English

by  Defense Technical Information Center

OPTIMIZATION OF FIT FOR MASS CUSTOMIZED APPAREL
ORDERING USING FIT PREFERENCE AND SELF MEASUREMENT
A Thesis
Presented to the Faculty of the Graduate School
of Cornell University
in Partial Fulfillment of the Requirements for the Degree of
Master of Science
DISTRIBUTION STATEMENT A
Approved for Public Release
Distribution Unlimited
by
Sean Frederick Ahrens
January 2000
© 2000 Sean Frederick Ahrens
ABSTRACT
Mass customized apparel production holds great promise for
revitalizing garment manufacturing in this country. Improved production
processes like flexible manufacturing, Computer Assisted Design (CAD),
Computer Assisted Manufacturing (CAM), and single-ply cutting have allowed
customized, single garment production runs to become cost effective. In
order for firms in the apparel industry to successfully implement this promising
new production program, ordering methodologies must be established that
provide customized garments with acceptable fit for the consumer. My first
hypothesis is that the inclusion of fit preference queries in an apparel ordering
model will improve the accuracy of size predictions. My second hypothesis is
that these fit preference queries combined with an optimized method of self-
measurement have the greatest potential to predict accurate garment sizes.
This study is designed to evaluate the effectiveness of such ordering models
using men's casual shorts as the primary test garment. I conducted research
in two phases with a pilot and primary test. Male, college students within a
specified waist size range were recruited and asked to report self-
measurements and fit preferences on a mock internet website. These
subjects were then scheduled for a fit testing session where they were
measured by expert evaluators and tried on a series of test shorts. The first
three short sizes presented were predicted using a size prediction model and
data from self-measurement, expert measurement, and self-measurement
plus reported fit preferences. In order to determine their optimum size, test
subjects assessed up to a total of six shorts until they selected a pair with the
perceived best fit. Subjects were also presented with a background
questionnaire that asked demographic and apparel purchasing questions.
After the completion of all fit testing sessions adjustments were made to the
size prediction model to enhance its effectiveness. Since collaborative
interaction between the manufacturer and the consumer is essential in the
ordering process for customized goods, the inclusion of fit preference queries
with guided self-measurement procedures should improve ordering accuracy
and selection of the optimum garment size. In the initial size prediction model
fit preference adjustments to self-measurements were found to significantly
improve optimum short size prediction accuracy. However, evidence to
support my second hypothesis that self-measurement plus fit preference was
a better predictor than expert measurement alone was not found in this study.
Wide variations in reported self-measurements hampered the significance
testing of fit preference adjustments and variations in garment positioning
limited the predictive ability of the size prediction models. Due to the
inaccuracies of short sizes predicted by self and expert measurement with
and without fit preference adjustments it is apparent that additional variables
may exist in the ordering process that can improve the accuracy of optimized
garment size predictions in addition to fit preferences. Identifying and
quantifying these variables may improve the optimum size selection for
apparel customers and allow mass customization to be an effective alternative
to mass production and made-to-measure manufacturing. Fit related
variables such as waist height, garment positioning, and the interplay of
garment style and fit characteristics with individual fit preferences may be the
essential elements missing or miscalculated in this ordering process. Fit
preference also requires additional research to determine its effectiveness in
improving the accuracy of size predictions for a wider range of body types and
mass customized apparel products.
BIOGRAPHICAL SKETCH
Sean Frederick Ahrens graduated from J. J. Pearce High School in
Richardson, Texas. He attended the University of Colorado, Colorado
Springs and graduated in August 1990 with a Bachelor of Science Degree in
Production Management. He was named the Top Production Management
student in his graduating class. He received an active duty US Army
commission in May 1990 through the Reserve Officer's Training Corps
(ROTC). He was designated the Top Cadet in his Regiment at ROTC
Advanced Camp.
Captain Ahrens' commissioned military training includes the Combined
Logistics Officer Advanced Course - Honor Graduate, the Petroleum Officer
Course - Honor Graduate, the Quartermaster Officer Basic Course -
Distinguished Honor Graduate, the Combat Developments Course - Honor
Graduate, and the US Army Airborne School. J
HI
to my loving wife, Amanda and our wonderful son, Christopher
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ACKNOWLEDGMENTS
Amanda Ahrens - for your unwavering support, inspiration, love, and
assistance, not only in this endeavor, but in our
entire lives together
Christopher Ahrens - for coming into our lives at just the right time and just
being yourself
Tove Hammer - for your guidance, direction, inspiration and invaluable
parenting tips
Susan Ashdown - for your patience, support, metal chairs, and work in
guiding me through every aspect of this undertaking
Suzanne Loker - for sharing your knowledge, mirror cleaning, and
scheduling of the graduate seminar in the face of
insurmountable obstacles
Anil Netravali - for your assistance in acceptance and dual degree
enrollment and candid discussions
Nathan Demerest - for being a great role model and mentor
Carol Young - for your sewing abilities and help on group projects
Melissa Kahn - for your patience and caring assistance
The US Army - for allowing me the opportunity to attend Cornell
University on a fully-funded basis
TABLE OF CONTENTS
CHAPTER 1 INTRODUCTION 1
1.1 Overview 1
1.2 Background 2
1.3 Apparel Industry Initiatives 5
1.4 Mass Customization 6
1.5 Garment Sizing 8
1.6 Research Objectives 9
1.7 Significance of Study 11
CHAPTER 2 REVIEW OF RELATED LITERATURE 13
2.1 Manufacturing Alternatives 13
2.1.1 Mass Production 14
2.1.2 Custom Manufacturing 21
2.1.3 Mass Customization 23
2.2 Sizing Systems 33
2.3 Garment Fit 35
2.4 Fit Preference 38
2.5 Measurement Techniques 42
2.6 Apparel Ordering 44
CHAPTER 3 RESEARCH DESIGN AND METHODOLOGY 46
3.1 Overview 46
3.2 Major Assumptions 48
3.3 Preliminary Analysis 50
3.3.1 Mail-Order Catalog Sizing 51
3.3.2 US Army ANSUR Data 55
3.3.3 Size Ranges 58
3.4 Test Shorts 59
3.5 Additional Test Instruments 68
3.5.1 Internet Website 71
3.5.2 Size Prediction Model 75
3.6 Measurement Procedures 84
VI
3.7 Subject Recruitment 88
3.8 Pilot Testing 90
3.9 Final Testing 93
3.10 Data Analysis 97
CHAPTER 4 RESULTS AND DISCUSSION 99
4.1 Sample Characteristics 99
4.2 Background Purchasing and Fit Preference 101
4.3 Size Prediction Model Results 107
4.4 Hypothesis Testing Results 119
4.5 Measurement Accuracy 125
4.6 Fit Testing Analysis 134
4.7 Fit Preference Findings 138
CHAPTER 5 MAJOR FINDINGS AND CONCLUSIONS 144
5.1 Major Findings 144
5.2 Summary and Conclusions 149
5.3 Recommendations for Future Research 151
APPENDIX A MAIL-ORDER CATALOG AND SIZING REVIEW 155
APPENDIX B TEST SHORT AND SIZE RANGE ANALYSIS 162
APPENDIX C SURVEY AND MEASUREMENT DATA 185
APPENDIX D DATA AND STATISTICAL ANALYSIS 195
APPENDIXE TEST FORMS 206
APPENDIX F EXPERT MEASUREMENTS 219
APPENDIX G RESEARCH WEBSITE 228
REFERENCES 268
VII
LIST OF TABLES
Table 2.1 Principles of Mass Production 18
Table 2.2 Features of Mass Customization 25
Table 3.1 Waist Circumference (Omphalion) 30 and Under Sample .... 58
Table 3.2 Ten Size Solution and Waist Size Ranges 59
Table 3.3 Pattern Crotch Length Adjustments in Centimeters 63
Table 3.4 Pattern Crotch Length Changes in Centimeters 64
Table 3.5 Final Pattern Crotch Length Sizes in Centimeters 65
Table 3.6 Expert Measurement Sizing Chart in Inches 76
Table 3.7 Self-Measurement Sizing Chart in Inches 77
Table 3.8 Initial Fit Preference Weights 79
Table 3.9 Fit Preference Adjustment Charts 80
Table 3.10 Intermediate Fit Preference Adjustments and Weighting 82
Table 3.11 Final Fit Preference Adjustments and Weighting 83
Table 4.1 Short Attribute Significance 105
Table 4.2 Initial Size Prediction Model Results 108
Table 4.3 Initial Size Prediction Model Total Error Rates 111
Table 4.4 Adjusted Size Prediction Model Results 115
Table 4.5 Adjusted Size Prediction Model Total Error Rates 117
Table 4.6 Girth Measurement Variances 127
Table 4.7 Self-Measurement Error Frequencies 132
Table 4.8 Test Short Presentation Order and Final Selections 135
Table 4.9 Fit Preference Adjusted Waist Size Accuracy 139
Table 4.10 Fit Preference Adjusted Crotch Size Accuracy 139
Table 4.11 Waist Height Prediction Errors 142
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