Travel Model Documentation


Travel Model Documentation

The links below provide SACOG’s travel model documentation, updated to reflect the SACSIM19 travel demand model used for the 2020 MTP-SCS.

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Full Model Documentation

Overview and Introduction

Table of Contents and Acknowledgements

1 Introduction

1.1 SACSIM Version

1.2 Version History

1.4 Report Organization

1.3 Public Access

2 Model Overview

2.1 Key Concepts and Parameters

2.2 Hardware and Software Requirements

2.3 Model Inputs

2.4 Model Outputs

2.5 Preparing a Model Run

Model Structure

3 Model Structure

3.1 DAYSIM Person Day Activity-Based Tour Simulation

3.2 Commercial Vehicle Travel

3.3 External Travel

3.4 Airport Passenger Ground Access Model

3.5 Trip Table Preparation and Assignment

3.6 Transit Assignment

Land Use

4 Land Use Data

4.1 Land Use for SACSIM Introduction

4.2 Land Use Data Files

4.3 SACSIM Parcel-Point Structure and Variables

4.4 Parcel Variables

4.5 SACSIM Land Use Spatial Association

4.6 SACSIM Parcel Land Use User Guide Setup

5 Representative Population Data

5.1 Land Use Scenarios

5.2 Household Population Demographics

5.3 Base Year Household Population Demographics

5.4 Future Year household_population demographics


6 Highway Networks

6.1 Opening and Editing the Highway Network

6.2 Capacity Classes

7 Transit Networks

7.1 Working with the Transit Network

7.2 Transit Lines

7.3 Transit Access Coding and Network Additions

7.4 Transit Travel Speeds and Stop Times

7.5 Park-and-Ride Locations

8 Bike and Walk Networks

8.1 Coding Bike Facilities into the Highway Network

8.2 Building Bike and Walk Skims

8.3 Estimating Bike and Walk Trip Distances

Auto Operating Cost, Fares, and Pricing

9 Auto Operating Costs and Transit Fares

9.1 Auto Operating Costs

9.3 Auto Operating Costs and Pricing User Guide Setup

9.2 Facility and Mileage Based Pricing

9.4 Transit Fares

Calibration and Validation

10 Model Equilibration

10.1 Background and Concepts

10.2 SACSIM19 Equilibrium Solution Procedure

11 Sensitivity Testing

11.1 Introduction

11.2 Experimental Testing of Key Exogenous Input Factors

11.3 Cross Section Testing of Land Use_Transportation Factors

11.4 Testing of Random Variation in Model

11.5 Facility-Based and Pay-as-You-Go Pricing Testing

12 Validation and Calibration

12.1 Observed Travel Data

12.2 Model Calibration

12.3 Model Validation and Reasonableness Check


Appendix A DAYSIM Reference Guide

Appendix B SACSIM Tolling Enhancments Memo (By RSG)

Appendix C Year 2000 SACOG Household Travel Survey Report

Appendix D Fuel Tax and Mileage Fee Report

Appendix E Caltrans 2019 Validation Memos Prepared by DKS Using SACSIM19 for SR 51 and I-5 Studies

Appendix F Circuity Surface Data Preparation Memo

Appendix G Run POPGEN

Appendix H SACOG Travel Behavior Report

Appendix I SACSIM VMT Calculation Procedures