How does network structure affect individuals at a local level? Do our decisions reflect population values at an aggregate level, or are they based on the local values of our friends and acquiantances?
This class explores these questions through the concept of adoption of innovation.
Adoption is generally driven by a social structure in which individuals can observe the decsions of their neighbors.
Informational effects result from peoples observing the choices made by others, from which they glean indirect information about what they know.
Direct benefit effects result from some sort of direct payoff by copying others behaviours.
According to Everett Rogers, the success of innovation (even if the innovation conveys a relative advantage) depends on 4 factors:
Complexity for people to understand and implement.
Observability, so that people can become aware that others are using it.
Trialability, so that people can mitigate its risks by adopting it gradually and incrementally.
Compatibility with the social system that it is entering. - E & K, 565
What are some possible barriers to innovation?
Players: v, w Strategies: A, B
How can this be applied for a group of neighbors?
$pda \geq (1-p)db$
$p \geq \frac{b}{a+b}$
Then, we can apply the coordination game on a network wide level. The simualation rules are simple:
This results in what we refer to as a cascade of adoptions.
A complete cascade occurs in the following conditions:
Using the above premise of information cascades, develop a set of rules for implementing a viral marketing campaign.
What do we mean by a densly connected community?
How do clusters interact with cascades?
Are the above statements true? Demonstrate it!
How do you think that the strength of ties affects diffusion?
In the real world, this model doesn't hold up. For example, some nodes are more influential than others, and some are more easily influenced than others. To compensate, we can say that payoff varies node by node:
In a collective action situation cross network collabortation is important and the underlying social network serves to transmit information about people's willingness to particpate.
Activities that present benefits only if a large quantity of people particpate.
Pluralistic ignorance is people have wildly erroneous estimates about the prevalence of certain opinions in the population at large.
How does network structure affect decisions about collective action?