13.1 Introduction
13.1.1 Overview
Microsimulation is the modeling and analysis of transportation networks and is used to assess the performance of highway and street systems, transit, and multi-modal facilities. These models analyze existing and future conditions and are useful in developing transportation solutions. To create a realistic and dependable model with reliable results, modelers are recommended to properly scope the project, choose the appropriate analysis tool, replicate existing conditions as accurately as possible, complete the analysis, and effectively summarize and document the results.
Microsimulation models are typically complex and demand experience and careful attention to detail to confirm accurate outputs. Because models are largely built on modeler-defined inputs and assumptions, it is recommended that modelers carefully analyze and report results. In addition to requiring strong modeling judgement, model development, debugging, and calibration are also resource-intensive processes. These processes are potentially more resource-intensive than other forms of analysis and it is recommended that care be given when deciding whether microsimulation is the correct method to analyze the project.
13.1.2 Purpose and Intended Use
The purpose of this chapter is to provide guidance on how to perform traffic analysis using microsimulation tools. This chapter discusses traffic analysis on freeways and arterials. Additionally, this chapter explains debugging and calibration methodology, alternative development, and reporting of results. This chapter can be used as guidance on any project that involves microsimulation.
13.1.3 Limitations
Content in this chapter is limited to an overview of how to apply microsimulation to a traffic analysis, including: guidance for scoping microsimulation projects, collecting data, developing the base model, calibrating the model, analyzing alternatives, and reporting results. The guidance provided in this chapter is generalized for all microsimulation software. Further guidance on coding model features not discussed in this chapter can be found in the respective tools’ user manuals. See
Chapter 2
and Chapter 12
of this manual for information on data collection and roundabouts in microsimulation, respectively.