1 Technical Decision - Making Process in Choosing Sub - Area Modeling Approaches

[ABSTRACT] The objective of this paper is to provide some guidance to transportation modelers or EMME/2 users to make right decisions in choosing cost-effective sub-area modeling approaches. Three approaches are presented here and they are as follows: 1) Focused Modeling Approach-aggregating and disaggregating regional Traffic Analysis Zones (TAZs), and enhancing the regional base network in the sub-areas of interest; 2) Stand-alone Sub-area Modeling Approach-using external stations as linkages to the regional areas, traversal trip matrix as inputs to external stations, and also building a detailed level of sub-area network; and 3) Direct Application of Regional Model Approach-enhancing the sub-area or corridor network in the sub-area of interest to reflect a greater detail roadway network. characteristic is the detailed network in the sub-area or corridor area. More often than not, their differences challenge planners and modelers to make a viable choice usually at the very beginning of a sub-area and corridor model development. The examples will demonstrate the technical decision-making process in choosing different modeling approaches to meet different modeling needs. Understanding the different characteristics, especially the pros and cons of each sub-area or corridor modeling approach, transportation modelers or EMME/2 users will benefit in saving time and costs by choosing the right sub-area modeling approach.