Diffusion of Innovations (3rd ed.)

Diffusion of Innovations (3rd ed.)

Contents
List of Case Illustrations  xiii
Preface  xv
Chapter 1  ELEMENTS OF DIFFUSION 1
WHAT IS DIFFUSION?  5
FOUR MAIN ELEMENTS IN THE DIFFUSION
OF INNOVATIONS  10
1.The Innovation  11
2. Communication Channels  17
3. Time  20
4. A Social System  24
SUMMARY34
Chapter 2 A HISTORY OFDIFFUSION RESEARCH .... 38
THE BEGINNINGS OF DIFFUSION RESEARCH
IN EUROPE  40
Gabriel Tarde and The Laws of Imitation 40
The British and German-Austrian Diffusionists  41
THE RISE OF DIFFUSION RESEARCH TRADITIONS. 42
Paradigms and Invisible Colleges  43
The Anthropology Research  Tradition  46
Early Sociology50
Rural Sociology57
Education 62
Public Health and Medical Sociology  65
Communication 72
Marketing 74
Geography 77
General Sociology  78
V
vi
Chapter 3
Contents
A TYPOLOGY OF DIFFUSION RESEARCH 79
SUMMARY 85
CONTRIBUTIONS AND CRITICISMS OF
DIFFUSION RESEARCH 87
THE CONTRIBUTIONS AND STATUS OF
DIFFUSION RESEARCH TODAY
CRITICISMS OF DIFFUSION RESEARCH  91
The Pro-Innovation Bias of Diffusion Research....
The Individual-Blame Bias in Diffusion Research
The Recall Problem in Diffusion Research
The Issue of Equality in the Diffusion of Innovations
GENERALIZING ABOUT DIFFUSION VIA
META-RESEARCH
Relating Theory and Research at the Middle Range
The Oversimplification of Two-Concept  Generalizations.
The Reliability of Diffusion  Generalizations
92
103
112
118
126
128
130
131
SUMMARY 133
Chapter 4  THE GENERATION OF INNOVATIONS . . .  134
THE INNOVATION-DEVELOPMENT PROCESS 135
1. Recognizing a Problem or Need  135
2. Basic and Applied Research  138
3. Development  139
4. Commercialization  143
5. Diffusion and Adoption  144
6. Consequences  149
SOCIOECONOMIC STATUS, EQUALITY, AND
INNOVATION DEVELOPMENT 153
TRACING THE INNOVATION-DEVELOPMENT
PROCESS 155
Shortcomings of the  Tracer Studies  157
Questions for Future Research  157
CONVERTING RESEARCH INTO PRACTICE  158
The Agricultural Extension  Model  159
Decentralized Diffusion  Systems  160
SUMMARY 161
Contents
Chapter 5 THE INNOVATION-DECISION  PROCESS 163
A MODEL OF THE INNOVATION-DECISION
PROCESS 163
KNOWLEDGE STAGE 164
Which Comes First, Needs or Awareness
of an  Innovation  ?  164
Types of Knowledge about an Innovation  167
Early  Versus Late Knowers of Innovations  168
PERSUASION STAGE 169
DECISION STAGE  172
IMPLEMENTATION STAGE 174
The End of  Implementation  175
Re-Invention 175
CONFIRMATION STAGE  184
Dissonance 185
Discontinuance 186
ARE THERE STAGES IN THEPROCESS?  191
Evidence of the Stages  192
Variance and Process Research  194
COMMUNICATION CHANNELS BY STAGES
IN THE INNOVATION-DECISION PROCESS 197
Categorizing Communication Channels  197
Mass Media  Versus Interpersonal Channels  198
Cosmopolite Versus Localite Channels  200
COMMUNICATIONCHANNELS BY ADOPTER
CATEGORIES 201
THE INNOVATION-DECISION PERIOD  202
Rate of Awareness-Knowledge and Rate of Adoption  202
Length of the Period by Adopter Category  203
SUMMARY 206
Chapter 6  ATTRIBUTES OF INNOVATIONS AND
THEIR RATE OFADOPTION  210
ATTRIBUTES OF INNOVATIONS 211
RELATIVE ADVANTAGE  213
Economic factors and Rate of Adoption  214
Status Aspects of Innovations  215
viii Contents
Relative Advantage and Rate of Adoption  217
Effects of Incentives  219
COMPATIBILITY 223
Compatibility with  Values and Beliefs  223
Compatibility with Previously Introduced Ideas  224
Compatibility with Needs  225
Compatibility and Rate of Adoption  226
Technology Clusters  226
Naming an Innovation  227
Positioning an Innovation  228
COMPLEXITY 230
TRIALABILITY 231
OBSERVABILITY 232
EXPLAINING RATE OF ADOPTION 232
THE DIFFUSION EFFECT 234
OVERADOPTION 236
SUMMARY 238
Chapter1INNOVATIVENESS AND ADOPTER
CATEGORIES 241
CLASSIFYING ADOPTER CATEGORIES ON THE
BASIS OF INNOVATIVENESS 242
The S-Curve of Adoption  and Normality  243
The Method of Adopter Categorization  245
ADOPTER CATEGORIES AS IDEAL TYPES 247
Innovators: Venturesome  248
Early Adopters: Respectable  248
Early Majority: Deliberate  249
Late Majority: Skeptical  249
Laggards: Traditional  250
CHARACTERISTICS OFADOPTER CATEGORIES.... 251
Socioeconomic Characteristics  251
.Personality Variables  257
Communication Behavior  258
A Summary of the Characteristics of
Adopter Categories  259
The Innovativeness-Needs Paradox  263
PREDICTING INNOVATIVENESS WITH
MULTIPLE CORRELATION TECHNIQUES . 265
Contents
COMPUTER SIMULATION OF INNOVATION
DIFFUSION 267
SUMMARY 268
Chapter 8  OPINION LEADERSHIP AND
DIFFUSION NETWORKS 271
MODELS OFMASS-COMMUNICATION FLOWS 272
Hypodermic Needle Model  272
The Two-Step Flow Model  272
HOMOPHILY-HETEROPHILY AND THE FLOW OF
COMMUNICATION 274
Homophily-Heterophily  274
Homophily as a Barrier to Diffusion  275
MEASURING OPINION LEADERSHIP AND
NETWORK LINKS 277
CHARACTERISTICS OF OPINION LEADERS 281
External Communication  282
Accessibility  282
Socioeconomic Status  282
Innovativeness 284
Innovativeness, Opinion Leadership, and
System Norms  284
MONOMORPHIC AND POLYMORPHIC OPINION
LEADERSHIP 288
DIFFUSION NETWORKS  293
Communication Network Analysis  294
The-Strength-of- Weak-Ties  295
Who Is Linked to  Whom in Networks?  299
SOCIAL LEARNING THEORY 304
Contrasting Social Learning and Diffusion  305
Horizons for Social Modeling  307
SUMMARY 307
Chapter 9  THE CHANGE AGENT 312
CHANGE AGENTS AS LINKERS 313
THE SEQUENCE OF CHANGE AGENT ROLES 315
Contents
FACTORS IN CHANGE AGENT SUCCESS  317
Change Agent Effort  317
Change Agency  Versus Client  Orientation  318
Compatibility with Clients' Needs  319
Change Agent Empathy327
HOMOPHILY AND CHANGE AGENT CONTACT .... 321
Change Agent  Contact  with  Lower-Status Clients  323
Paraprofessional Aides  325
Change Agent  Credibility  328
InauthenlicProfessionalization of Aides  331
OPINION LEADERS 331
CLIENTS' EVALUATIVE ABILITY 332
CENTRALIZED AND DECENTRALIZED
DIFFUSION SYSTEMS 333
The Classical Diffusion Model  333
Comparing Centralized Versus Decentralized
Diffusion Systems  334
Advantages and Disadvantages of Decentralized
Diffusion 337
SUMMARY 343
Chapter 10 INNOVATION IN ORGANIZATIONS 347
ORGANIZATIONS 348
ORGANIZATIONAL INNOVATIVENESS 355
Shortcomings of Organizational Innovativeness
Studies 356
Size and Organizational Innovativeness  358
Structural Characteristics and Organizational
Innovativeness 359
STAGES IN THE INNOVATION PROCESS IN
ORGANIZATIONS 361
A Model of the Innovation Process in Organizations  362
Time Sequence of the Stages in  the Innovation Process....  365
SUMMARY 370
Chapter 11  CONSEQUENCES  OF INNOVATIONS 371
A MODEL FOR STUDYING CONSEQUENCES 375
WHY HAVEN'T CONSEQUENCES BEEN
STUDIED MORE?  375
Contents
CLASSIFICATIONS OF CONSEQUENCES 379
Desirable Versus Undesirable Consequences  380
Direct Versus Indirect Consequences  384
Anticipated Versus Unanticipated Consequences  387
EQUALITY IN THE CONSEQUENCES
OF INNOVATIONS 391
The Issue of Equality in Development Programs  392
The Communication Effects Gap and
the Consequences of Diffusion  394
Gap-Widening  Consequences of the Adoption
of Innovations  398
Social Structure and the Equality of Consequences  401
Strategies for Narrowing  Gaps  403
Wider Gaps Are Not Inevitable  408
SUMMARY AND CONCLUSIONS 410
Bibliography 414
Name Index  441
Subject Index  447