Motivation
Objectives
network perspective on complex systems
examples for complex networks
Questions
- what does the complex networks perspective add to the study of complex systems?
- [Try] a more related and global analysis perspective?
- What is the difference between the network perspective and the agent-based modeling approach?
- [Try] network: global, agent-based: local.
- Wrong. See below.
- Describe the micro and macro perspective on complex networks. What distinguishes them?
- [Try] micro: individual, on one node/edge, e.g. the degree of one node; macro: systemic properties, e.g. the number of nodes/edges, more general, doesn’t cover the detail of the individual compoenent in the network. The information’s object distinguish them, whether the information is used to describe a single component.
- Give two examples for complex systems that can be studied from a network perspective.
- [Try] academic author citation situation; the spread of virus.
- Consider an example for a complex system: what is the micro-and the macro level?
- [Try] author citation network. micro: the citation number of each paper, macro: the distribution of the citation number.
- Define three macroscopic features of networks and use them to classify the example networks of this lecture
- [Try] the degree distribution, the density, the direction. The component coefficient.
- Give two examples for link semantics that result in undirected and directed links.
- [Try] directed: <a,b>, undirected: (a,b)
Keywords
- agent-based modeling
- complex network basic conceptions
- network observations
- Micro/Macro perspective
Agent-based modeling
| Agent-based modeling | network perspective | |
|---|---|---|
| Focus | Internal dynamics of agents, e.g how agent make decisions | Topology |
| Show Format | group, mean field, etc | Nodes and links |
| More | Feedback between agent dynamics and interactions | dyadic interactions |
There is no hard separation between these two approaches.
Complex Systems
- a large number of subsystems -> can be reduced
- agents/subsystems strongly interacte with each other.
complex network
an abstract graphical representation of complex system.
Micro-Macro
the micro-macro link: relate microscopic details of a model to the macroscopic features of the system that it will generate (and vice-versa).
Usage:
- explain large-scale patterns of the system based on microscopic behavior.
- design microscopic behavior to achieve desirable systemic properties.
Examples
technology systems: e.g. computer network (Internet), power grid infrastructure
social systems: friendship, communication, scientific community
Category Nodes Links Examples Technology system engineered artifacts transport lines computer network (internet), power grid infrastructure Social system actors social ties friendship, communication, scientific community, hierarchy relationships Information system knowledge artifact semantic relations scholarly citations biological system biological entities biological interactions gene regulartory network economic system actors interactions financial transaction, trade relation
Obervations of network
| Perspective | Detail |
|---|---|
| structure | regular, random, complex |
| connectedness | closely connected, diameter |
| heterogeneity | degree distribution |
