Abstract. The observance of unpredictable episodes of clustered volatility in some data series has led to the development of models of social processes that will give rise to such clustered volatility. Such models are not, however, validated directly against qualitative evidence about the behaviour of individuals and how they interact. An agent based simulation model of the effect of drought on domestic water consumption is reported here that is the outcome of a process of development involving stakeholders to inform and validate the model qualitatively at micro level while ensuring that numerical outputs from the model cohere with observed time series data. We argue that this cross-validation of agent based social simulation models is a significant advancement in the analysis of social process.
The issues.The relationship between social processes and institutions and social statistics has been an important and controversial issue in sociology at least since the publication in 1904-5 of Max Weber's The Protestant Ethic and the Spirit of Capitalism (Weber 1958). In this paper, we are concerned with that relationship. We argue that, on the basis of the evidence of social enquiry, analytic models do not obviously explain important properties of social statistics. However, a class of simulation models does generate numerical outputs that are consistent with important properties of real social statistics. These models have two further properties that should be of consuming interest to sociologists. One is that they appear to produce data with empirically relevant properties because they capture features of social order that are the subject of sociological enquiry -the social embeddedness of individuals together with the emergence of social norms. The other is that these models naturally draw upon and cohere with the sort of detailed, qualitative studies of social processes found in core strands of the sociological literature.Our central argument can be seen as an operationalisation of some elements of structuration theory (Giddens 1984). According to Blaikie (1993), Giddens proposed that social research can take place at four related levels: (1) hermeneutic elucidation of frames of meaning, (2) investigation of context and form of practical consciousness, (3) identification of bounds of knowledgeability and (4) specification of institutional orders. Of these four levels, says Blaikie, the first two are "micro" and best investigated qualitatively while the second two are "macro" and best investigated with quantitative methods. This view is very close to ours. The micro behaviour is the behaviour of observed actors and described by autonomous software modules called agents. The macro behaviour is the behaviour of a social institution (organisation, community, set of customers, or whatever) or a collection of such institutions and is described by the properties of the model containing the agents. The properties of the model as a whole are amenable to summary using descriptive statistics while the behaviour of the indivi...