The Diffusion of Innovations

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Lecture 13

• The Diffusion of Innovations

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What is Diffusion of Innovation?

• It is not so much about what researchers or
  inventors innovate it is more about what people
  adopt.

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Definition of Diffusion of Innovation

• the process by which an innovation is
  communicated through certain channels over time
  among the members of a social system (Rogers
  1983)

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Four Basic Concepts in Diffusion of Innovation

• Innovation
• Idea, object, or practice that is perceived as
  new
• Channels of Communication
• Means by which info is transmitted to or within
  the social system
• Time
• Rate at which the innovation is diffused or the
  relative speed with which it is adopted
• Social System
• Individuals, organizations, or agencies that are
  potential adopters of the innovation

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Common Scope of Diffusion Research

• (1) Characteristics of an innovation which may
  influence its adoption
• (2) Decision-making process that occurs when
  individuals consider adopting a new innovation
• (3) The characteristics of individuals that make
  them likely to adopt the innovation
• (4) The consequences for individuals and society
  of adopting the innovation
• (5) Communication channels used in the adoption
  process

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Various Early Diffusion Studies
Adapted from Mahajan and Peterson (1985)
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Purpose of Diffusion Models

• To depict the successive increase in the number
  of adopters over time.
• Permits prediction of the continued development
  of the diffusion process.
• Facilitates a theoretical explanation of the
  dynamics of the diffusion process.

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Who uses this stuff?

• Marketers!
• Movie studios
• Political and Interest groups

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Foundations of Research on Diffusion of
Innovations

• Gabriel Tarde (1903)
• Proposed the S-shaped curve
• As it turned out, study after study tended to
  show the exact same S-shaped curve when
  researchers plot the rate of adoption over time.

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Diffusion S Curve
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Foundations of Research on Diffusion of
Innovations

• Ryan and Gross (1943)
• Categories of Adopters (relative time of
  adoption)
• Innovators
• Early adopters
• Early/Late Majorities
• Laggards

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Opinion Leadership

• Opinion leaders are key for influence and thus
  ability to successfully diffuse an innovation.
• Opinion leaders are concentrated among the early
  adopters, not the innovators.

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Adopter Categories
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Stages of Adoption

• Everett Rogers (1995)
• Awareness
• Interest
• Evaluation
• Trial
• Adoption

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Categorizing Adopters and Non-Adopters

• Adoption
• accept and use innovation
• Nonadoption
• nontrial of an innovation
• Discontinuance
• rejection of an innovation after it has
  previously been adopted

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Epidemic Models

• Based on simple examination of spread
• Simplest version is basic exponential model
• Central-source model

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Epidemic Models (continued)

• Modified spread model
• Diffusion works through word-of-mouth (i.e.,
  previous users)