Adopter categories based on standard deviation parameters of the normal bell curve (Everett Rogers):

• Innovators: Beyond $(\bar{x} - 2\sigma) \implies 2.5\%$
• Early Adopters: Between $(\bar{x} - 2\sigma)$ and $(\bar{x} - \sigma) \implies 13.5\%$ (Correct)
• Early Majority: Between $(\bar{x} - \sigma)$ and $\bar{x} \implies 34.0\%$
• Late Majority: Between $\bar{x}$ and $(\bar{x} + \sigma) \implies 34.0\%$
• Laggards: Beyond $(\bar{x} + \sigma) \implies 16.0\%$

Communication channel dynamics across innovation stages (Everett Rogers):

• Generalization 5-1: Mass media channels (A) and cosmopolite channels (C) are relatively more important at the Knowledge stage to create widespread initial awareness.
• Generalization 5-2: Interpersonal channels (B) and localite channels (D) are relatively more important at the Persuasion and Decision stages to form/change attitudes and mitigate adoption risk.
• Newspapers (E) are a prototypical mass media channel that conveys newly released technological news broadly.

Everett M. Rogers defines diffusion as 'the process by which (1) an innovation is communicated through (2) certain channels (3) over time among the members of (4) a social system.'
The four main elements are: The Innovation (A), Communication Channels (B), Time, and the Social System (C).
Awareness (D) and Interest (E) are individual mental steps in the traditional 5-stage adoption model (AIETA), not macro elements of the diffusion process.