Implementation of the Delta/Start Model.

This working paper outlines the steps undertaken to develop a dynamic land use transport model. The model is based around an existing transport modelling suite, called START, which has been applied to many urban areas in the UK and abroad. However, its integration with an explicit land use model (called DELTA) was new, and this paper describes the first implementation of the combined dynamic land use transport model for the study area of Fife and Lothian region. The model was used in a PhD thesis and an EPSRC ‘Sustainable Cities’ research project at the Institute for Transport Studies. The paper discusses the processes involved in the full implementation of this model, involving both software development, modification to existing software, and implementation. However, it focuses in particular upon the data requirements and calibration of the various submodels in DELTA. In general the model dataset has been generated using existing study area data from past START applications, plus data from the 1991 Census of population and employment. Not all the disaggregations of data required by the model were available from published, or on-line, sources, and so several disaggregations were undertaken. A feature of the model is that the calibration is undertaken for each submodel individually. In general, the model made use of past research into the relationships that it represents, combined with the judgement of the model developers where no other data was available. The implementation of the location model is discussed in detail, including the use of environmental variables in location choice. This fulfils the main aim of this paper; to provide the technical background for the research projects that make use of this model implementation

Macro-SAMs for modelling purposes: an application to Portugal in 2003

Knowledge of the quantifiable side of a market economy greatly depends on the form of macro-economic modelling that is used. This, in turn, should have an underlying database. Such a database should include the interrelated subsystems that exist within that economy and, at the same time, it should be adaptable for modelling purposes, whilst also being flexible and consistent, in order to allow for aggregations and disaggregations. Based on the geographical limits of a European country and the time limit of one year (1 January to 31 December), this paper proposes, as a possible database, a Social Accounting Matrix (SAM) constructed from the national accounts, operating within the framework of the European System of National and Regional Accounts in the European Community of 1995 (ESA 95). Using a numerical version of a SAM, constructed from the Portuguese national accounts for 2003, at a highly aggregated level, the aim of this paper is to show the differences between a matrix format of the national accounts, as proposed by the ESA 95 and the United Nations System of National Accounts for 1993 (SNA 93), from which it is constructed, and the SAM, emphasizing its potentialities as a database for modelling purposes. Some considerations will also be made about the relationship between SAMs and Input-Output tables