Attributed Hierarchical Port Graphs and Applications

Abstract

We present attributed hierarchical port graphs (AHP) as an extension of port graphs that aims at facilitating the design of modular port graph models for complex systems. AHP consist of a number of interconnected layers, where each layer defines a port graph whose nodes may link to layers further down the hierarchy; attributes are used to store user-defined data as well as visualisation and run-time system parameters. We also generalise the notion of strategic port graph rewriting (a particular kind of graph transformation system, where port graph rewriting rules are controlled by user-defined strategies) to deal with AHP following the Single Push-out approach. We outline examples of application in two areas: functional programming and financial modelling.

A Strategic Graph Rewriting Model of Rational Negligence in Financial Markets

“…Whilst ABMs rely on the internal processing of its agents, GTSs provide at each point in time a holistic view of the system state and a visual trace of the specific rules that trigger specific behaviours. In future, we will further develop the model using hierarchical graphs [12] to capture all tiers of the model, and also generalise the rules to permit dynamic changes in key attributes such as asset toxicity and costs.…”

Implementation of a Port-graph Model for Finance

“…We also carry out a thorough validation of the model with respect to its equational specification producing a base case that provides an effective platform for incrementally increasing the complexity and scope of the model. In a previous work; [2], we have defined a hierarchical port-graph extension useful in producing a more integrated model.…”