A framework designed for social scientists to model human agent behaviour in social networks
In the context of applied psychology modelling human behaviour is intensively discussed. There are various psychological theories that focus on psychological aspects of decision making and on communication aspects. It is obvious to analyze these questions by the means of modelling and simulation. In this situation, the modeller has two main problems: Firstly, there are lot of very detailed investigations on psychological phenomena but all these theories are quite isolated to each other and do not give an integrated and comprehensive view on the relevant process. Secondly, for formulating the model and for simulating it later on, there is no support on software level.
In this situation an efficient software concept is needed which brings together the very special objectives of the innovative and continuously developing thematic scope and a scalable and payable software architecture to work with. This paper introduces such a software concept. Preconditions for the work are a communication network simulator and a psychological model for a human agent. The network enables the modeller to specify communication networks between the modelled individuals, the agents and executes a simple next-event-simulation mechanism with a discrete time-model. The agent model structures the psychological components and processes participating in decision making.
The main part of the paper analyzes the use cases for the planned software system as initialize the network, initialize an agent, observe trajectories, simulate, analyze results, change parameter values, change agent behaviour, and focuses on the special problems caused by applying these tasks to the field of agent based communication models. On the base of these deliberations an adequate software architecture is proposed. Thereby, the following conflicts had to be solved:
- Complexity of the model versus design of the user interface.
- Universal software system versus easily adaptable simulation program.
- User interface versus highly specialized interventions on behaviour programming level.
- Object oriented programming paradigm versus (procedural) programming skills of the social scientists.
These conflicts concentrate on a cost benefit problem concerning universal system and comfortable user interface on the one hand and on the problem of the access level for the inexperienced user on the other. The decisions made for models following the ATASIS meta model are as follows: The graphical user interface gives support only for simple standard functions. Higher functionality is accessible by the interface of the database system and its query language directly. For the model description level the argumentation is more complex. The solution is realized as follows:
- Model structure in strong analogy to the psychological theory.
- Strongly sequential runtime algorithm.
- Dataflow by message mechanism between the psychological components.
- Updating the model code by the use of a standard development environment.
So far, the conflict between a proper object-oriented design of the modelling and simulation software environment for the ATASIS meta model and the usability by users without deepened programming skills is discussed. For the complete project of model development, this paper tries to motivate
- A sophisticated balance between user skills and higher concepts of object oriented programming paradigm: We just used the concepts of modularisation but no heritage and no method concepts.
- The cost benefit calculations for the user interface, which lead to very pragmatic solutions especially for non standard application areas of simulation methodology.
- The intensive analyse of user demands which leads to smaller and more efficient solutions.
- The concept of the expert-mode interface for access to model code and data base which leads to an open system architecture with only negligible cut backs in comfort.
- The acceptance and integration of user skills which has restricting effects concerning programming experiences however very positive effects concerning the use of the database interface including its query language.