Mid-Term Diffusion Models

Question 1

different types of models (5)

Answer 1

1. exponential model
2. external influence model
3. logistic model
4. gompertz model
5. bass model

Question 2

critical mass

Answer 2

sufficient number of adopters of an innovation in a social system so that rate of adoption becomes self-sustaining

Question 3

exponential growth model

Answer 3

assumptions:

• no seasonality, no age structure, unlimited resources
• main problem: no limit on growth

Question 4

model use

Answer 4

to study the evolution of the number of adopters of a technology

Question 5

external influence model

Answer 5

• number of resources is not unlimited, population can not grow forever
• number of new adopters in specific point in time is proportional to the number of potential adopters

Question 6

logistic model

Answer 6

introduces an imitation effect, upper limit effect, relative growth rate diminishes when the population gets higher values

Question 7

imitation effect

Answer 7

adoption and diffusion of technology is based on the imitation of the behaviour of previous adopters

Question 8

r0

Answer 8

maximum possible growth rate of the population

- net effect of reproduction and mortality

Question 9

K

Answer 9

saturation level; upper limit for the number of members of the population
- carrying capacity

Question 10

growth time

Answer 10

the length of the interval during which growth progresses from 10% to 90% of the carrying capacity

Question 11

midpoint

Answer 11

time where the members of the population are half the carrying capacity

Question 12

gompertz model

Answer 12

• growth is slowest at the start and end of a time period
• based on the assumption that the adoption rate is proportional to the logarithm of the number of potential adopters
• maximum adoption rate occurs when the adopters population has reached 37% of carrying capacity

Question 13

bass model

Answer 13

exponential growth, capacity limit, imitation effect, and innovation effect

Question 14

research goals (3)

Answer 14

1. to find a common representation of innovation diffusion patterns across a large variety of ICTs
2. to identify different classes of ICT having similar diffusion patterns in terms of the parameters of their diffusion curves
3. To explore the relationship between innovation characteristics of the ITs and their general diffusion patterns

Question 15

model best fit

Answer 15

least squares method, minimizes the sum of squared residuals

• model that best fits to the series of data

Question 16

innovation effect

Answer 16

capability to incorporate a new technology